Form N-CSR is to be used by management investment companies to file reports with the Commission not later than 10 days after the transmission to stockholders of any report that is required to be transmitted to stockholders under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1). The Commission may use the information provided on Form N-CSR in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-CSR, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-CSR unless the Form displays a currently valid Office of Management and Budget (“OMB”) control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. § 3507.

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Beginning on January 1, 2021, as permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Funds’ shareholder reports will no longer be sent by mail, unless you specifically request paper copies of the reports from the Funds or from your financial intermediary, such as a broker-dealer or bank. Instead, the reports will be made available on www.oberweisfunds.com and you will be notified by mail each time a report is posted and provided with a website link to access the report.

If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the Funds or your financial intermediary electronically by contacting us at 1-800-245-7311.

You may elect to receive all future reports in paper free of charge. You can inform the Funds or your financial intermediary that you wish to continue receiving paper copies of your shareholder reports by contacting us at 1-800-245-7311. Your election to receive reports in paper will apply to all funds held with the fund complex.

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PRESIDENT’S LETTER (unaudited)

Dear Fellow Oberweis Funds Shareholder,

2020 IN REVIEW

The International Opportunities, Emerging Markets, China Opportunities and Global Opportunities Funds all exceeded their benchmark returns by a very wide margin in 2020. The International Opportunities Fund returned 62.86% (versus 22.93% for the MSCI World ex-US Small Cap Growth Index). The China Opportunities Fund returned 56.51% (compared to 29.49% for the MSCI China Net Index). The Emerging Markets Fund returned 42.81% (versus 19.29% for the MSCI EM Small Cap Index). Among the domestic funds, the Micro-Cap Fund and Small-Cap Opportunities Fund returned 29.91% and 32.47%, respectively (compared to 40.13% and 34.63% for the Russell Micro-Cap Growth and Russell 2000 Growth indices). The Micro-Cap and Small-Cap Opportunities funds faced a material headwind in 2020: both are consistently underweight biotech companies, which posted strong gains in 2020 and have all-time-high exposure within their respective benchmarks. The Global Opportunities Fund, which invests in many of our team’s top ideas around the world, returned 55.55% versus 16.33% for the MSCI ACWI Small-Cap Index.

This year of COVID-19 has been truly remarkable. In March, global equities experienced one of the fastest and deepest plunges of our careers, only to come roaring back in the second quarter, and continued to accelerate upward in the third and fourth quarters. This year’s rally can be at least partially attributable to massive monetary stimulus from the Federal Reserve, as well as fiscal stimulus from governments around the world. To combat the crisis, the Fed quickly reduced interest rates to almost zero and promised to keep them there for a prolonged period. Globally, many central banks followed suit. Meanwhile, fiscal stimulus from the CARES Act provided cash payments to most US taxpayers and significant relief for business owners via the Payroll Protection Program’s forgivable loans. This coordinated stimulus plan flooded the US economy with cash, and some of that cash made it back to the stock market, driving a strong rally in equity prices.

In addition, as the year went on, doomsday scenarios began to fade. Fears of a COVID-19 depression following the explosion in unemployment have greatly abated. Many have already returned to work and the end of (or at least sharp reduction in) the pandemic’s impact is now within sight. In November, Pfizer-BioNTech’s vaccine showed stunning efficacy in clinical trials. Shortly thereafter, Moderna demonstrated similarly high success with its own vaccine. Three more vaccines are now in Phase 3 clinical trials. With President Biden promising 100 million vaccinations in his first 100 days, investors appear to be looking past the end of COVID-19, with experts such as Dr. Anthony Fauci predicting a return to some degree of normalcy by the autumn of 2021. While new variants continue to pose risks, the consensus view is that pandemic economic disruption is likely to sharply fade by the end of 2021.

Political uncertainty in the US was also a concern late in 2020, although with President Biden’s inauguration we now expect the focus to shift to his economic policies, which may be less favorable to investors. Biden will bring a sense of stability and predictability that was absent under Trump. He’ll propose further stimulus and large-scale infrastructure spending. But that will come at a price, namely higher taxes or increased deficits. It surprises us that investors have not reacted more negatively to the prospect of higher personal and corporate income taxes, in addition to the possibility of higher capital gains taxes. Given Biden’s slim majority in Congress, material tax changes are not a given and may take time to procure. It’s hard to predict how and when tax legislation will unfold, but this remains a risk that keeps us up at night, especially given the budget deficit impacts of COVID stimulus.

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PRESIDENT’S LETTER (unaudited) (continued)

In Europe, concerns of a chaotic breakup between the UK and the European Union also seem less likely, following the last-minute signing of the Trade and Cooperation Agreement (TCA) in December 2020. The agreement’s title is an ironic misnomer for a divorce pact. Irrespective, the risk of a no-deal EU breakup is far less worrisome. In Asia, China’s remarkable success in containing the virus has permitted its economy to mostly avoid the shutdowns prevalent throughout the US and Europe. Not surprisingly, China’s equity market was among the hottest in 2020. It remains to be seen how the Biden presidency will affect US-China trade tensions, but they probably won’t get worse in the near term.

OUTLOOK

The relentless equity rally in the final three quarters of 2020 reflects a system flush with liquidity and marginally diminished risks relative to the beginning of the year. The pandemic has ignited innovation, creativity, and change – trends that tend to positively benefit our investment process. Certain niches – like ecommerce, home delivery, and video conferencing – have grown much faster than anticipated. The pandemic will fade in 2021, but we believe the changes and impacts to business will be long lasting, and that our team’s track record of investing in companies at the cusp of material change positions us well.

In the near term, we expect a strong economic rebound in the second half of 2021, which is already the consensus view. Over the longer term, watch inflation, interest rates and tax policy, as we expect these variables to become increasingly important for investor sentiment. Over a full market cycle, we believe our ability to add alpha lies not in macroeconomic forecasting but rather with superior individual stock selection. Accordingly, we will continue to focus on stock fundamentals, seeking to identify companies with long-term earnings power well above the expectations of other analysts and investors.

VALUATION RECAP

While valuations for US large cap stocks are near historical highs, US small-cap and international valuations are closer to historical means. As of December 31, 2020, the price/earnings (P/E) ratio was 19.2 times for the Global Opportunities Fund (versus 22.0 last quarter), 15.4 times for the Small-Cap Opportunities Fund (versus 14.9 last quarter), 12.0 times for the Micro-Cap Fund (versus 18.3 last quarter), 18.6 times for the International Opportunities Fund (versus 25.6 last quarter), 24.6 times for the China Opportunities Fund (versus 27.4 last quarter), and 26.1 times for the Emerging Markets Fund (versus 25.1 times last quarter). Each of these funds invests in companies with expected earnings growth rates that are higher than that of the broader market, and in companies expected to grow faster than current market expectations. As of December 31, 2020, the weighted-average market capitalization was $4.8 billion for the Global Opportunities Fund, $3.6 billion for the Small-Cap Opportunities Fund, $1.7 billion for the Micro-Cap Fund, $4.6 billion for the International Opportunities Fund, $3.6 billion for the Emerging Markets Fund, and $129.3 billion for the China Opportunities Fund. Note that the China Opportunities Fund’s market cap is skewed upward due to two mega-cap holdings; the median market cap of the fund was $16.4 billion.

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MANAGEMENT DISCUSSION ON FUND PERFORMANCE

(UNAUDITED)

MARKET ENVIRONMENT

Global equities returned 15.90% in 2020, as measured by the MSCI World Index. Global small-caps, as measured by the MSCI World Small-Cap Index, performed similarly, returning 15.96%. Foreign small-caps underperformed U.S. small-caps, as evidenced by the 12.78% return on the MSCI World ex-USA Small Cap Index. Internationally, small-cap growth equities outperformed small-cap value by 2035 basis points, with the MSCI World ex-USA Small Cap Growth Index returning 22.93% versus only 2.58% for the MSCI World ex-USA Small Cap Value Index.

Within the United States, large-cap growth stocks outperformed small-cap growth stocks by 386 basis points, as measured by the respective returns of the Russell 1000 Growth (38.49%) and Russell 2000 Growth (34.63%) indices. Within domestic small-cap, growth outperformed value, with the Russell 2000 Growth Index outperforming the Russell 2000 Value Index (4.63%) by 3000 basis points for the year. The Russell Micro-Cap Growth Index (40.13%) outperformed the Russell 2000 Growth Index by 550 basis points.

DISCUSSION OF THE OBERWEIS FUNDS

The International Opportunities Fund returned 62.86% versus 22.93% for the MSCI World ex-US Small-Cap Growth Index. The portfolio benefitted from stock selection in Japan and Sweden while stock selection in Canada and the U.K. detracted from performance. On a sector level, the portfolio benefitted from stock selection in information technology and consumer discretionary while performance was negatively impacted by stock selection in utilities and financials. At the stock level, Sinch AB (SINCH SS), Baycurrent Consulting (6532 JT), and Evolution Gaming Group AB (EVO SS) were among the top contributors to performance; Air Canada (AC CN), Redrow PLC (RDW LN) and Capita PLC (CPI LN) were among the top detractors.

The Global Opportunities Fund returned 55.55% versus 16.33% for the MSCI ACWI Small-Cap Index. At the country level, the portfolio benefitted from favorable stock selection in the USA, Sweden, and Japan, partially offset by adverse stock selection in Canada, Taiwan and Brazil. At the sector level, the Fund was positively impacted by stock selection in industrials, healthcare, and consumer discretionary. The fund also benefitted from an overweight in technology. The fund was slightly adversely affected by stock selection in materials. At the stock level, Upwork (UPWK US), Sinch AB (SINCH SS), and Caredx (CDNA US) were among the top contributors to performance; Skywest Inc (SKYW US), Air Canada (AC CN) and Skyline Champion Corp (SKY US) were among the top detractors.

The China Opportunities Fund returned 56.51% compared to 29.49% for the MSCI China Index. The portfolio benefitted from favorable stock selection in industrials, consumer discretionary, and healthcare. The fund also benefitted from an overweight allocation and favorable stock selection in information technology. The fund’s underweight allocation in financials also helped performance. At the stock level, Nio Inc (NIO US), Tencent Holdings (700 HK) and Meituan (3690 HK) were among the top contributors; Sunac China Holdings (1918 HK), China Life Insurance Co Ltd H (2628 HK), and Jiangsu Yoke Technology (002409 CH) were among the top detractors.

The Emerging Markets Fund returned 42.81% versus 19.29% for the MSCI EM Small Cap Index. At the country level, the portfolio benefitted from stock selection in China, India, and South Korea, slightly offset by detracting stock selection in Taiwan. At the sector level, the fund was positively impacted by stock selection in health care, industrials, and consumer staples, while stock selection in information technology slightly detracted from performance.

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(UNAUDITED) (continued)

At the stock level, Seegene Inc (096530 KS), Jiangsu Hengli Hydraulic (601100 CH), and Weimob Inc (2013 HK) were among the top contributors to performance; Linx SA (LINX3 BZ), UPL Ltd (UPLL IN), and IDP Education Ltd (IEL AU) were among the top detractors.

The Micro-Cap Fund returned 29.91% versus 40.13% for the Russell Micro-Cap Growth Index. Performance was adversely impacted by stock selection in consumer discretionary and producer durables. At the stock level, Digital Turbine (APPS), Magnite (MGNI), and CareDx (CDNA) were among the top contributors to performance. Recro Pharma (REPH), Skywest (SKYW), and Cardtronics (CATM) were among the top detractors.

The Small-Cap Opportunities Fund returned 32.47% versus 34.63% for the Russell 2000 Growth Index. The fund benefitted from stock selection in healthcare, while stock selection in energy and consumer discretionary detracted from performance. Livongo (LVGO), Upwork (UPWK), and Bandwidth (BAND) were among the top contributors to performance. Recro Pharma (REPH), Gray Television (GTN), and Cardtronics (CATM) were among the top detractors.

The portfolio turnover rates were 129% for the Global Opportunities Fund, 92% for the Micro-Cap Fund, 147% for the Small-Cap Opportunities Fund, 192% for the China Opportunities Fund, 130% for the International Opportunities Fund and 131% for the Emerging Markets Fund. The net expense ratios for the investor share class of the Funds were 1.53% for Global Opportunities, 1.58% for Micro-Cap, 1.55% for Small-Cap Opportunities, 1.95% for China Opportunities, 1.60% for International Opportunities and 1.75% for Emerging Markets.

For current performance information, please visit www.oberweisfunds.com.

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MANAGEMENT DISCUSSION ON FUND PERFORMANCE

(UNAUDITED) (continued)

Oberweis Micro-Cap Fund

At December 31, 2020

	Asset Allocation (% of Net Assets)
	Equities					99.0
	Other Assets less Liabilities					1.0

	Top Ten Holdings (% of Net Assets)
	Magnite, Inc.					5.7
	CareDx, Inc.					4.3
	Upwork, Inc.					3.9
	Castle Biosciences, Inc.					3.8
	Digital Turbine, Inc.					3.8
	Alphatec Hldgs. Inc.					3.1
	Golden Nugget Online Gaming, Inc.					2.7
	Ameresco, Inc.					2.5
	ChannelAdvisor Corp.					2.5
	The Shyft Group, Inc.					2.5

	Top Ten Industries (% of Net Assets)
	Computer Services Software & Systems					21.7
	Biotechnology					6.5
	Medical Equipment					4.8
	Specialty Retail					4.7
	Diversified Manufacturing Operations					4.3
	Production Technology Equipment					4.2
	Medical & Dental Instruments & Supplies					4.2
	Commercial Vehicles & Parts					3.6
	Back Office Support, Human Resources & Consulting					3.0
	Healthcare Services					2.5

Oberweis Small-Cap Opportunities Fund

At December 31, 2020

	Asset Allocation (% of Net Assets)
	Equities					100.5
	Other Liabilities less Assets					(0.5)

	Top Ten Holdings (% of Net Assets)
	Upwork, Inc.					5.5
	CareDx, Inc.					3.6
	Shutterstock, Inc.					3.4
	Tupperware Brands Corp.					3.1
	Tempur Sealy International, Inc.					2.9
	Castle Biosciences, Inc.					2.9
	ChannelAdvisor Corp.					2.6
	Inmode Ltd.					2.2
	Golden Nugget Online Gaming, Inc.					2.0
	Masonite International Corp.					2.0

	Top Ten Industries (% of Net Assets)
	Computer Services Software & Systems					21.6
	Building Materials					6.6
	Diversified Manufacturing Operations					5.2
	Healthcare Services					5.1
	Back Office Support, Human Resources, & Consulting					4.7
	Medical Equipment					4.7
	Biotechnology					4.0
	Semiconductors & Components					3.6
	Textiles Apparel & Shoes					3.4
	Household Equipment & Products					3.1

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(UNAUDITED) (continued)

Oberweis Global Opportunities Fund

At December 31, 2020

	Asset Allocation (% of Net Assets)
	Equities					101.0
	Other Liabilities less Assets					(1.0)

	Top Ten Holdings (% of Net Assets)
	Upwork, Inc.					6.5
	CareDX, Inc.					5.0
	Castle Biosciences, Inc.					3.8
	Sinch AB					3.3
	IR Japan Hldgs. Ltd.					3.1
	BHG Group AB					2.6
	ChannelAdvisor Corp.					2.6
	M31 Technology Corp.					2.5
	II-VI, Inc.					2.2
	Deckers Outdoor Corp.					2.1

	Top Ten Industries (% of Net Assets)
	Software					14.8
	Professional Services					9.6
	Semiconductor & Semiconductor Equipment					9.2
	Internet & Direct Marketing Retail					8.7
	Healthcare Provider & Services					5.8
	Biotechnology					5.0
	Information Technology Services					4.1
	Hotels, Restaurants & Leisure					4.0
	Household Durables					3.9
	Healthcare Equipment & Supplies					3.6

Oberweis China Opportunities Fund

At December 31, 2020

	Asset Allocation (% of Net Assets)
	Equities					101.4
	Other Liabilities less Assets					(1.4)

	Top Ten Holdings (% of Net Assets)
	Tencent Hldgs. Ltd.					6.1
	Alibaba Group Hldg. Ltd.					5.9
	Meituan Dianping					2.5
	Li Ning Co. Ltd.					2.5
	21Vianet Group, Inc. ADS					2.3
	Contemporary Amperex Technology Co. Ltd.					2.2
	JD.com, Inc.					2.1
	GDS Hldgs. Ltd.					1.9
	Wuxi Biologics, Inc.					1.8
	TAL Education Group ADS					1.8

	Top Ten Industries (% of Net Assets)
	Internet & Direct Marketing Retail					12.8
	Interactive Media & Services					6.8
	Real Estate Management & Development					5.1
	Electronic Equipment, Instruments & Components					5.1
	Machinery					4.6
	Household Durables					4.4
	Life Sciences Tools & Services					4.3
	Insurance					4.3
	Metals & Mining					4.3
	Electrical Equipment					4.2

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(UNAUDITED) (continued)

Oberweis International Opportunities Fund

At December 31, 2020

	Asset Allocation (% of Net Assets)
	Equities					97.7
	Other Assets less Liabilities					2.3

	Top Ten Holdings (% of Net Assets)
	Sinch AB					5.6
	Sushiro Global Hldgs. Ltd.					5.4
	BayCurrent Consulting, Inc.					4.4
	IR Japan Hldgs. Ltd.					3.1
	BASE, Inc.					3.0
	Intermediate Capital Group PLC					2.9
	M&A Capital Partners Co. Ltd.					2.8
	Pharmaron Beijing Co. Ltd.					2.8
	BHG Group AB					2.7
	Constellium SE					2.7

	Top Ten Industries (% of Net Assets)
	Software					9.2
	Entertainment					8.6
	Capital Markets					7.6
	Professional Services					7.5
	Internet & Direct Marketing Retail					7.4
	Information Technology Services					6.5
	Healthcare Technology					5.7
	Hotels, Restaurants & Leisure					5.4
	Metals & Mining					4.7
	Machinery					4.2

Oberweis Emerging Markets Fund

At December 31, 2020

	Asset Allocation (% of Net Assets)
	Equities					98.8
	Rights					0.1
	Other Assets less Liabilities					1.1

	Top Ten Holdings (% of Net Assets)
	M31 Technology Corp.					3.4
	Dada Nexus Ltd. ADS					3.4
	Affle India Ltd.					3.1
	NHN KCP Corp.					2.1
	Varun Beverages Ltd.					2.0
	LEENO Industrial, Inc.					2.0
	POSCO Chemical Co. Ltd.					2.0
	LandMark Optoelectronics Corp.					1.9
	IDP Education Ltd.					1.9
	Wizz Air Hldgs. PLC					1.8

	Top Ten Industries (% of Net Assets)
	Semiconductors & Semiconductor Equipment					12.6
	Internet & Direct Marketing Retail					8.2
	Software					6.9
	Machinery					6.1
	Information Technology Services					5.4
	Multiline Retail					4.4
	Diversified Consumer Services					4.3
	Oil, Gas & Consumable Fuels					4.3
	Beverages					4.0
	Diversified Telecommunication Services					3.8

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(UNAUDITED) (continued)

Average Annual Total Returns1 (for the Periods Ended December 31, 2020)

	1 YR (%)		5 YR (%)		10 YR (%)		SINCE INCEPTION2 (%)		EXPENSE RATIO3 (%)
OBMCX		29.91		17.23		13.60		10.69		1.58
OMCIX4		30.20		17.49		13.87		10.96		1.33
Russell Microcap Growth		40.13		13.08		11.57		N/A5

Growth of a $10,000 Investment (from January 1, 1996 to December 31, 2020)

[MISSING IMAGE: tm214310d1-lc_obmcxpn.jpg]

1 Performance data represents past performance, which is no guarantee of future results. Current performance may be higher or lower than the performance shown. You can obtain performance data current to the most recent month by visiting oberweisfunds.com. Returns are historical and include changes in share price and reinvestment of dividends and capital gains. Investment return and principal value will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. The Oberweis Funds invest in rapidly growing smaller and medium sized companies, which may offer greater return potential. However, these investments often involve greater risks and volatility. There is no guarantee that the portfolios can achieve their objectives.

The Russell Microcap Growth Index measures the performance of those Russell microcap companies with higher price-to-book ratios and higher forecasted growth values. The Russell Microcap Growth Index is represented by the smallest 1,000 securities in the small cap Russell 2000 Index plus the next 1,000 securities. The Russell Index is unmanaged and is not available for investment.

2 Since Inception returns are from commencement of operations on 01/01/96 for the Fund.

3 Expense ratio is the total annual net fund operating expense ratio as of 12/31/20. The expense ratio gross of any fee waivers or expense reimbursement was 1.59% and 1.34% for the Investor Class and Institutional Class, respectively.

4 The Institutional share class (OMCIX) began on May 1, 2017, returns for prior periods represent synthetic returns.

5 The Russell Microcap Growth Index began on July 3, 2000, and the line graph for the Index begins at the same value as the Fund on that date.

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(UNAUDITED) (continued)

Average Annual Total Returns1 (for the Periods Ended December 31, 2020)

	1 YR (%)		5 YR (%)		10 YR (%)		SINCE INCEPTION2 (%)		EXPENSE RATIO3 (%)
OBSOX		32.47		15.69		12.31		8.03		1.55
OBSIX4		32.80		15.98		12.60		8.30		1.30
Russell 2000 Growth		34.63		16.36		13.48		8.15

Growth of a $10,000 Investment (from September 15, 1996 to December 31, 2020)

[MISSING IMAGE: tm214310d1-lc_obsoxpn.jpg]

The Russell 2000 Growth Index measures the performance of those Russell 2000 companies with higher price-to-book ratios and higher forecasted earnings growth rates. The Russell Index is unmanaged and is not available for investment.

2 Since Inception returns are from commencement of operations on 09/15/96 for the Fund.

3 Expense ratio is the total annual net fund operating expense ratio as of 12/31/20. The expense ratio gross of any fee waivers or expense reimbursement was 2.03% and 1.78% for the Investor Class and Institutional Class, respectively.

4 The Institutional share class (OBSIX) began on May 1, 2017, returns for prior periods represent synthetic returns.

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(UNAUDITED) (continued)

Average Annual Total Returns1 (for the Periods Ended December 31, 2020)

	1 YR (%)		5 YR (%)		10 YR (%)		SINCE INCEPTION2 (%)		EXPENSE RATIO3 (%)
OBEGX		55.55		13.78		11.11		9.42		1.53
OBGIX4		55.94		14.06		11.38		9.69		1.27
MSCI ACWI Small-Cap		16.33		11.39		8.82		N/A5

Growth of a $10,000 Investment (from January 7, 1987 to December 31, 2020)

[MISSING IMAGE: tm214310d1-lc_obegxpn.jpg]

The MSCI ACWI Small-Cap Index (Net) is a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of small cap developed and emerging markets with dividends reinvested net of withholding tax. A sales load of 4% was charged on the Oberweis Global Opportunities Fund until 12/31/91 and is not reflected in the total return figures or graph above.

2 Since Inception returns are from commencement of operations on 01/07/87 for the Fund.

3 Expense ratio is the total annual net fund operating expense ratio as of 12/31/20. The expense ratio gross of any fee waivers or expense reimbursement was 1.53% and 1.28% for Investor Class and Institutional Class, respectively.

4 The Institutional share class (OBGIX) began on May 1, 2017, returns for prior periods represent synthetic returns.

5 The MSCI ACWI Small-Cap Index began on May 31, 1994, and the line graph for the index begins at the same value as the Fund on that date.

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(UNAUDITED) (continued)

Average Annual Total Returns1 (for the Periods Ended December 31, 2020)

	1 YR (%)		5 YR (%)		10 YR (%)		SINCE INCEPTION2 (%)		EXPENSE RATIO3 (%)
OBCHX		56.51		17.31		9.79		14.31		1.95
OCHIX4		56.79		17.60		10.06		14.59		1.69
MSCI China Net		29.49		15.05		7.61		11.51

Growth of a $10,000 Investment (from October 1, 2005 to December 31, 2020)

[MISSING IMAGE: tm214310d1-lc_obchxpn.jpg]

1 Performance data represents past performance, which is no guarantee of future results. Returns are historical and include changes in share price and reinvestment of dividends and capital gains. Current performance may be higher or lower than the performance shown. You can obtain performance data current to the most recent month by visiting oberweisfunds.com. The principal value and investment return of an investment will fluctuate so that your shares, when redeemed, may be worth more or less than their original cost. The Oberweis Funds invest in rapidly growing smaller and medium sized companies, which may offer greater return potential. However, these investments often involve greater risks and volatility. Foreign and emerging market investing involves special risks such as currency fluctuation and less public disclosure, as well as economic and political risk. There is no guarantee that the portfolios can achieve their objectives.

The MSCI China Net Index is a free float-adjusted market capitalization-weighted Index of Chinese equities that include China-affiliated corporations and H shares listed on the Hong Kong Exchange, and B shares listed on the Shanghai and Shenzhen exchanges and P chips and foreign listings with minimum dividends reinvested net of withholding tax. The MSCI China net index is unmanaged and is not available for investment.

2 Since Inception returns are from commencement of operations on 10/01/05 for the Fund.

3 Expense ratio is the total annual net fund operating expense ratio as of 12/31/20. The expense ratio gross of any fee waivers or expense reimbursement was 1.95% and 1.69% for Investor Class and Institutional Class, respectively.

4 The Institutional share class (OCHIX) began on May 1, 2017, returns for prior periods represent synthetic returns.

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(UNAUDITED) (continued)

Average Annual Total Returns1 (for the Periods Ended December 31, 2020)

	1 YR (%)		5 YR (%)		10 YR (%)		SINCE INCEPTION2 (%)		EXPENSE RATIO3 (%)
OBIOX		62.86		14.96		14.54		11.50		1.60
MSCI World ex-US Small Cap Growth		22.93		11.88		8.32		5.96

Growth of a $10,000 Investment (from February 1, 2007 to December 31, 2020)

[MISSING IMAGE: tm214310d1-lc_obioxpn.jpg]

The MSCI World ex-US Small Cap Growth Index is a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of small cap growth developed and emerging markets excluding the U.S., with minimum dividends reinvested net of withholding tax.

2 Since Inception returns are from commencement of operations on 02/01/07 for the Fund.

3 Expense ratio is the total annual net fund operating expense ratio as of 12/31/20. The expense ratio gross of any fee waivers or expense reimbursement was 1.87%.

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(UNAUDITED) (continued)

Average Annual Total Returns1 (for the Periods Ended December 31, 2020)

	1 YR (%)		SINCE INCEPTION2 (%)		EXPENSE RATIO3 (%)
OBEMX		42.81		12.86		1.75
OIEMX		43.15		13.13		1.50
MSCI EM Small-Cap		19.29		3.95

Growth of a $10,000 Investment (from May 1, 2018 to December 31, 2020)

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The MSCI EM Small-Cap Index (Net) is a free float-adjusted market capitalization weighted index that measures the performance of Small-Cap stocks in 24 emerging markets.

2 Since Inception returns are from commencement of operations on 05/01/2018 for the Fund.

3 Expense ratio is the total annual net fund operating expense ratio as of 12/31/20. The expense ratio gross of any fee waivers or expense reimbursement was 3.79% and 3.54% for Investor Class and Institutional Class, respectively.

TABLE OF CONTENTS

Oberweis Micro-Cap Fund

Schedule of Investments December 31, 2020

	Shares		Value
Equities – 99.0%
Air Transport – 1.3%
Air Transport Services Group, Inc.*		31,100		$	974,674
Back Office Support, Human Resources & Consulting – 3.0%
CRA International, Inc.		18,500			942,205
Cross Country Healthcare, Inc.*		63,800			565,906
Heidrick & Struggles International, Inc.		27,000			793,260
					2,301,371
Banks — Diversified – 1.4%
First Foundation, Inc.		26,300			526,000
Mercantile Bank Corp.		19,500			529,815
					1,055,815
Biotechnology – 6.5%
Avid Bioservices, Inc.*		95,500			1,102,070
Castle Biosciences, Inc.*		43,700			2,934,455
Collegium Pharmaceutical, Inc.*		46,000			921,380
					4,957,905
Building Materials – 2.4%
Griffon Corp.		36,800			749,984
Masonite International Corp.*		10,900			1,071,906
					1,821,890
Casinos & Gambling – 0.5%
Full House Resorts, Inc.*		100,000			393,000
Commercial Vehicles & Parts – 3.6%
Commercial Vehicle Group, Inc.*		98,000			847,700
The Shyft Group, Inc.		66,600			1,890,108
					2,737,808
Communications Technology – 2.5%
ADTRAN, Inc.		39,800			587,846
Ooma, Inc.*		59,400			855,360
Ribbon Communications, Inc.*		72,000			472,320
					1,915,526
Computer Services Software & Systems – 21.7%
A10 Networks, Inc.*		88,100			868,666
ChannelAdvisor Corp.*		119,800			1,914,404
Digital Turbine, Inc.*		51,275			2,900,114
Magnite, Inc.*		142,377			4,372,398

See accompanying notes to the financial statements.

TABLE OF CONTENTS

Oberweis Micro-Cap Fund (continued)

Schedule of Investments December 31, 2020

	Shares		Value
Model N, Inc.*		39,200		$	1,398,656
Perficient, Inc.*		22,500			1,072,125
Upland Software, Inc.*		24,100			1,105,949
Upwork, Inc.*		87,000			3,003,240
					16,635,552
Consumer Electronics – 1.4%
VOXX International Corp.*		82,300			1,050,148
Diversified Manufacturing Operations – 4.3%
Golden Nugget Online Gaming, Inc.*		103,000			2,029,100
Inmode Ltd.*		26,800			1,272,464
					3,301,564
Drug & Grocery Store Chains – 0.5%
Natural Grocers by Vitamin Cottage, Inc.		31,200			428,688
Energy Equipment – 2.5%
Ameresco, Inc.*		36,808			1,922,850
Engineering & Contracting Services – 1.4%
MYR Group, Inc.*		17,600			1,057,760
Financial Data & Systems – 1.0%
International Money Express, Inc.*		48,000			744,960
Healthcare Facilities – 0.7%
The Joint Corp.*		20,000			525,200
Healthcare Services – 2.5%
Addus HomeCare Corp.*		9,900			1,159,191
The Ensign Group, Inc.		10,500			765,660
					1,924,851
Home Building – 1.3%
M/I Homes, Inc.*		22,000			974,380
Household Equipment & Products – 2.4%
Tupperware Brands Corp.*		57,400			1,859,186
Household Furnishings – 1.4%
Flexsteel Industries, Inc.		30,000			1,049,100
Machinery — Industrial – 1.6%
EnPro Industries, Inc.		16,400			1,238,528

See accompanying notes to the financial statements.

TABLE OF CONTENTS

Oberweis Micro-Cap Fund (continued)

Schedule of Investments December 31, 2020

	Shares		Value
Medical & Dental Instruments & Supplies – 4.2%
Alphatec Hldgs. Inc.*		164,600		$	2,389,992
Antares Pharma, Inc.*		200,600			800,394
					3,190,386
Medical Equipment – 4.8%
Accuray, Inc.*		83,800			349,446
CareDx, Inc.*		45,400			3,289,230
					3,638,676
Oil Well Equipment & Services – 1.7%
Helix Energy Solutions Group, Inc.*		83,300			349,860
Patterson-UTI Energy, Inc.*		114,000			599,640
RPC, Inc.*		100,283			315,891
					1,265,391
Pharmaceuticals – 0.5%
BioDelivery Sciences International, Inc.*		88,600			372,120
Production Technology Equipment – 4.2%
Axcelis Technologies, Inc.*		34,900			1,016,288
Cohu, Inc.*		31,676			1,209,390
Ultra Clean Hldgs., Inc.*		33,600			1,046,640
					3,272,318
Recreational Vehicles & Boats – 1.6%
Malibu Boats, Inc.*		19,100			1,192,604
Restaurants – 0.9%
El Pollo Loco Hldgs., Inc.*		38,000			687,800
Scientific Instruments — Control & Filter – 1.8%
LiqTech International, Inc.*		168,729			1,349,832
Scientific Instruments — Electrical – 1.9%
Allied Motion Technologies, Inc.		18,600			950,460
Preformed Line Products Co.		7,000			479,080
					1,429,540
Scientific Instruments — Gauges & Meters – 0.7%
Vishay Precision Group, Inc.*		17,800			560,344

See accompanying notes to the financial statements.

TABLE OF CONTENTS

Oberweis Micro-Cap Fund (continued)

Schedule of Investments December 31, 2020

	Shares		Value
Semiconductors & Components – 2.5%
CEVA, Inc.*		16,600		$	755,300
MagnaChip Semiconductor Corp.*		85,300			1,153,256
					1,908,556
Specialty Retail – 4.7%
Boot Barn Hldgs., Inc.*		28,400			1,231,424
Sonic Automotive, Inc.		23,700			914,109
Zumiez, Inc.*		40,300			1,482,234
					3,627,767
Technology — Miscellaneous – 1.7%
Camtek Ltd.*		58,980			1,292,252
Telecommunications Equipment – 2.2%
Clearfield, Inc.*		21,600			533,952
Vocera Communications, Inc.*		28,100			1,166,993
					1,700,945
Textiles Apparel & Shoes – 1.3%
Crocs, Inc.*		16,000			1,002,560
Truckers – 0.4%
Daseke, Inc.*		70,000			406,700
Total Equities
(Cost: $47,329,311)				$	75,768,547
Total Investments – 99.0%
(Cost: $47,329,311)				$	75,768,547
Other Assets Less Liabilities – 1.0%					778,414
Net Assets – 100%				$	76,546,961

* Non-income producing security during the period ended December 31, 2020

See accompanying notes to the financial statements.

TABLE OF CONTENTS

Oberweis Small-Cap Opportunities Fund

Schedule of Investments December 31, 2020

	Shares		Value
Equities – 100.5%
Air Transport – 1.0%
Air Transport Services Group, Inc.*		5,300		$	166,102
Auto Part – 0.7%
Adient PLC*		3,500			121,695
Back Office Support, Human Resources, & Consulting – 4.7%
ASGN, Inc.*		3,200			267,296
TriNet Group, Inc.*		2,800			225,680
TTEC Hldgs., Inc.		4,000			291,720
					784,696
Banks — Diversified – 0.8%
First Foundation, Inc.*		6,500			130,000
Banks — Savings, Thrifts & Mortgage Lending – 0.7%
Flagstar Bancorp, Inc.		3,000			122,280
Biotechnology – 4.0%
Castle Biosciences, Inc.*		7,200			483,480
Halozyme Therapeutics, Inc*.		4,400			187,924
					671,404
Building Materials – 6.6%
Builders FirstSource, Inc.*		5,900			240,779
Gibraltar Industries, Inc.*		2,100			151,074
Masonite International Corp.*		3,400			334,356
Patrick Industries, Inc.		2,700			184,545
Trex Co., Inc.*		2,200			184,184
					1,094,938
Commercial Finance & Mortgage Companies – 0.8%
PennyMac Financial Services, Inc.		2,000			131,240
Communications Technology – 0.7%
Bandwidth, Inc.*		800			122,936
Computer Services Software & Systems – 21.6%
CACI International, Inc.*		1,100			274,263
ChannelAdvisor Corp.*		27,200			434,656
CommVault Systems, Inc.*		3,400			188,258
LivePerson, Inc.*		2,900			180,467
ManTech International, Corp.		1,600			142,304
Model N, Inc.*		7,500			267,600
Rapid7, Inc.*		3,200			288,512
Shutterstock, Inc.		8,000			573,600
SPS Commerce, Inc.*		1,200			130,308
Upland Software, Inc.*		4,500			206,505
Upwork, Inc.*		26,400			911,328
					3,597,801

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis Small-Cap Opportunities Fund (continued)

Schedule of Investments December 31, 2020

	Shares		Value
Computer Technology – 2.6%
Synaptics, Inc.*		3,200		$	308,480
Synnex Corp.		1,600			130,304
					438,784
Diversified Manufacturing Operations – 5.2%
Concentrix Corp.*		1,600			157,920
Golden Nugget Online Gaming, Inc.*		17,100			336,870
Inmode Ltd.*		7,800			370,344
					865,134
Diversified Retail – 1.2%
BJ’s Wholesale Club Hldgs., Inc.*		5,500			205,040
Education Services – 1.8%
Chegg, Inc.*		3,400			307,122
Electronic Components – 1.4%
II-VI, Inc.*		3,000			227,880
Energy Equipment – 1.5%
Arcosa, Inc.		4,600			252,678
Financial Data & Systems – 1.6%
Green Dot Corp.*		4,800			267,840
Foods – 0.7%
B&G Foods, Inc.		4,400			122,012
Forest Products – 1.2%
UFP Industries, Inc.		3,500			194,425
Healthcare Facilities – 1.5%
Select Medical Hldgs. Corp.*		9,100			251,706
Healthcare Services – 5.1%
Acadia Healthcare Co., Inc.*		5,300			266,378
Addus HomeCare Corp.*		1,500			175,635
Amedisys, Inc.*		450			131,999
The Ensign Group, Inc.		3,700			269,804
					843,816

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis Small-Cap Opportunities Fund (continued)

Schedule of Investments December 31, 2020

	Shares		Value
Home Building – 1.1%
M/I Homes, Inc.*		4,300		$	190,447
Household Equipment & Products – 3.1%
Tupperware Brands Corp.*		15,800			511,762
Household Furnishings – 2.9%
Tempur Sealy International, Inc.*		18,100			488,700
Insurance — Property Casualty – 1.5%
Stewart Information Services Corp.		5,000			241,800
Machinery — Industrial – 1.7%
Hillenbrand, Inc.		6,900			274,620
Medical & Dental Instruments & Supplies – 2.3%
Cantel Medical Corp.*		2,300			181,378
Merit Medical Systems, Inc.*		3,500			194,285
					375,663
Medical Equipment – 4.7%
CareDX, Inc.*		8,200			594,090
Tandem Diabetes Care, Inc.*		1,900			181,792
					775,882
Medical Services – 0.9%
NeoGenomics, Inc.*		2,700			145,368
Oil Well Equipment & Services – 2.1%
Helmerich & Payne, Inc.*		7,300			169,068
NOV, Inc.*		12,800			175,744
					344,812
Personal Care – 0.8%
Helen of Troy Ltd.*		570			126,648
Production Technology Equipment – 0.6%
Ultra Clean Hldgs., Inc.*		3,400			105,910
Real Estate Services – 1.0%
Realogy Hldgs. Corp.*		12,600			165,312
Scientific Instruments — Pollution Control – 1.8%
Clean Harbors, Inc.*		4,000			304,400
Semiconductors & Components – 3.6%
Advanced Energy Industries, Inc.*		1,300			126,061
MACOM Technology Solutions Hldgs. Inc.*		3,300			181,632
MaxLinear. Inc.*		7,600			290,244
					597,937
Shipping – 1.6%
Matson, Inc.		4,700			267,759
Specialty Retail – 1.0%
Sonic Automotive, Inc.		4,400			169,708

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis Global Opportunities Fund

Schedule of Investments(a) December 31, 2020

	Shares		Value
Equities – 101.0%
Brazil – 1.4%
Arco Platform Ltd.*		12,700		$	450,723
B2W — Cia Digital*		30,000			436,699
					887,422
Canada – 0.9%
Ritchie Bros. Auctioneers, Inc.		8,200			569,987
China – 8.4%
21Vianet Group, Inc. ADS*		25,700			891,533
Bilibili, Inc. ADS*		8,900			762,908
Ever Sunshine Lifestyle Services Group Ltd.*		444,000			975,093
GDS Hldgs. Ltd.*		52,000			606,024
Pharmaron Beijing Co. Ltd.		63,200			1,068,498
Weimob, Inc.*		517,000			931,994
					5,236,050
Denmark – 1.2%
ALK-Abello AS*		1,900			782,621
Finland – 3.7%
Metso Outotec Oyj*		127,000			1,276,020
QT Group Oyj*		15,000			1,055,461
					2,331,481
Germany – 1.2%
Shop Apotheke Europe NV*		4,300			778,475
Hong Kong – 1.3%
Minth Group Ltd.*		150,000			793,596
Japan – 10.3%
Capcom Co. Ltd.		10,000			648,527
IR Japan Hldgs. Ltd.		12,100			1,938,591
Kobe Bussan Co. Ltd.		37,200			1,142,970
MedPeer, Inc.*		12,000			951,084
PCA Corp.*		18,000			784,511
Sushiro Global Hldgs. Ltd.		25,000			959,048
					6,424,731
Netherlands – 2.7%
ASM International NV*		4,000			872,847
BE Semiconductor Industries NV*		13,400			804,653
					1,677,500
Norway – 1.7%
Nordic Semiconductor ASA*		66,900			1,074,776

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis Global Opportunities Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
South Korea – 1.0%
LEENO Industrial, Inc.		5,000		$	621,822
Sweden – 10.5%
BHG Group AB*		74,100			1,617,675
Boozt AB*		25,200			578,423
Evolution Gaming Group AB		8,900			894,758
MIPS AB		11,400			714,798
Sinch AB*		12,900			2,097,865
Stillfront Group AB*		57,000			691,765
					6,595,284
Taiwan – 3.4%
M31 Technology Corp.		132,000			1,590,214
Wiwynn Corp.		21,000			527,315
					2,117,529
United Kingdom – 9.7%
Blue Prism Group PLC*		31,900			749,120
Endava PLC ADS*		9,600			736,800
Focusrite PLC*		39,600			582,114
Gamesys Group PLC		41,000			638,200
GB Group PLC		45,800			585,974
Intermediate Capital Group PLC		53,900			1,268,201
Oxford Instruments PLC		27,700			755,987
Spirent Communications PLC		212,700			768,954
					6,085,350
United States of America – 43.6%
Addus HomeCare Corp.*		4,700			550,323
Alphatec Hldgs., Inc.*		83,700			1,215,324
Amedisys, Inc.*		2,400			703,992
Bandwidth, Inc.*		3,200			491,744
BJ’s Wholesale Club Hldgs., Inc.*		22,500			838,800
CACI International, Inc.*		4,800			1,196,784
CareDX, Inc.*		43,000			3,115,350
Castle Biosciences, Inc.*		35,700			2,397,255
ChannelAdvisor Corp.*		100,600			1,607,588
Crocs, Inc.*		9,500			595,270
Deckers Outdoor Corp.*		4,500			1,290,510
II-VI, Inc.*		18,300			1,390,068
Magnite, Inc.*		40,000			1,228,400
Model N, Inc.*		16,700			595,856
Rapid7, Inc.*		9,500			856,520
Shutterstock, Inc.		11,400			817,380
Synaptics, Inc.*		8,500			819,400
Tandem Diabetes Care, Inc.*		11,200			1,071,616
Tempur Sealy International, Inc.*		22,400			604,800
Trex Co., Inc.*		7,200			602,784

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis Global Opportunities Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
Tupperware Brands Corp.*		38,400		$	1,243,775
Upwork, Inc.*		118,600			4,094,071
					27,327,610
Total Equities
(Cost: $39,469,431)				$	63,304,234
Total Investments – 101.0%
(Cost: $39,469,431)				$	63,304,234
Other Liabilities Less Assets – (1.0)%					(629,247)
Net Assets – 100%				$	62,674,987

a Certain securities were fair valued under the discretion of the Board of Trustees. (See Note 2)

* Non-income producing security during the period ended December 31, 2020

ADS — American depositary share

Sector Allocations (As A Percentage of Net Assets) (unaudited)
Communication Services					4.1%
Consumer Discretionary					22.7%
Consumer Staples					3.2%
Financials					2.0%
Health Care					18.9%
Industrials					15.1%
Information Technology					35.0%

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis China Opportunities Fund

Schedule of Investments(a) December 31, 2020

	Shares		Value
Equities – 101.4%
Air Freight & Logistics – 0.6%
S.F. Hldg. Co. Ltd.*		50,000		$	674,651
Auto Components – 2.4%
Changzhou Xingyu Automotive Lighting Systems Co. Ltd.*		15,001			460,556
Fuyao Glass Industry Group Co. Ltd.*		200,000			1,100,853
Minth Group Ltd.*		250,000			1,322,660
					2,884,069
Automobiles – 2.3%
BYD Co. Ltd.*		30,000			789,842
Great Wall Motor Co. Ltd.*		300,000			1,032,170
NIO, Inc. ADS*		20,000			974,800
					2,796,812
Banks – 0.8%
China Merchants Bank Co. Ltd.*		150,000			948,900
Beverages – 2.8%
Kweichow Moutai Co. Ltd.		4,475			1,367,554
Shanxi Xinghuacun Fen Wine Factory Co. Ltd.*		12,000			689,368
Wuliangye Yibin Co. Ltd.*		30,085			1,343,607
					3,400,529
Capital Markets – 0.9%
Huatai Securities Co. Ltd.		400,007			1,101,967
Chemicals – 1.8%
Guangzhou Tinci Materials Technology Co. Ltd.*		75,057			1,193,081
Jiangsu Eastern Shenghong Co. Ltd.*		700,000			1,015,448
					2,208,529
Commercial Service & Supply – 2.5%
Ever Sunshine Lifestyle Services Group Ltd.		960,000			2,108,310
Times Neighborhood Hldgs. Ltd.		1,000,000			936,756
					3,045,066
Diversified Consumer Services – 3.9%
China Education Group Hldgs. Ltd.*		350,000			675,097
New Oriental Education & Technology Group, Inc.*		10,500			1,885,327
TAL Education Group ADS*		30,000			2,145,300
					4,705,724

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis China Opportunities Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
Electrical Equipment – 4.2%
Contemporary Amperex Technology Co. Ltd.		48,002		$	2,583,723
Sungrow Power Supply Co. Ltd.*		150,000			1,660,929
Xinjiang Goldwing Science & Technology Co. Ltd.*		400,000			806,032
					5,050,684
Electronic Equipment, Instruments & Components – 5.1%
Delta Electronics, Inc.*		130,000			1,219,133
Hangzhou Hikvision Digital Technology Co. Ltd.*		160,005			1,187,440
Luxshare Precision Industry Co. Ltd.		133,753			1,149,513
Maxscend Microelectronics Co. Ltd.*		14,000			1,222,729
Sunny Optical Technology Group Co. Ltd.		60,000			1,310,901
					6,089,716
Entertainment – 0.9%
Bilibili, Inc. ADS*		13,000			1,114,360
Food Products – 1.6%
Sichuan Teway Food Group Co. Ltd.*		60,000			755,592
Tongwei Co. Ltd.*		200,000			1,176,226
					1,931,818
Healthcare Providers & Services – 1.5%
Aier Eye Hospital Group Co. Ltd.		156,000			1,787,533
Hotels, Restaurants & Leisure – 3.8%
Galaxy Entertainment Group Ltd.*		150,000			1,167,674
Jiumaojiu International Hldgs. Ltd.*		550,000			1,675,895
Songcheng Performance Development Co. Ltd.*		200,055			542,484
Xiabuxiabu Catering Management Hldgs. Co. Ltd.*		530,000			1,211,169
					4,597,222
Household Durables – 4.4%
Ecovacs Robotics Co. Ltd.*		49,903			676,175
Gree Electric Appliances, Inc. of Zhuhai		140,000			1,326,986
Hangzhou Great Star Industrial Co. Ltd.*		300,077			1,429,860
Midea Group Co. Ltd.		119,942			1,806,376
					5,239,397
Insurance – 4.3%
AIA Group Ltd.*		110,000			1,340,465
China Life Insurance Co. Ltd.		650,000			1,430,956
New China Life Insurance Co. Ltd.*		400,000			1,560,281
Ping An Insurance Group Co. of China Ltd.		72,000			876,206
					5,207,908
Interactive Media & Services – 6.8%
Autohome, Inc. ADS*		9,000			896,580
Tencent Hldgs. Ltd.		101,000			7,267,286
					8,163,866
Internet & Direct Marketing Retail – 12.8%
Alibaba Group Hldg. Ltd.*		242,000			7,038,412
Dada Nexus Ltd. ADS*		10,000			365,000

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis China Opportunities Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
JD.com, Inc.*		56,000		$	2,466,360
JD Health International, Inc.*		25,000			483,715
Meituan*		80,000			3,011,457
Pinduoduo, Inc. ADS*		11,000			1,954,370
					15,319,314
Internet Software & Services – 2.3%
21Vianet Group, Inc. ADS*		80,000			2,775,200
Information Technology Services – 1.9%
GDS Hldgs. Ltd.*		196,968			2,295,525
Life Sciences Tools & Services – 4.3%
Pharmaron Beijing Co. Ltd.		85,000			1,437,062
WuXi AppTec Co. Ltd.		81,000			1,588,985
Wuxi Biologics, Inc.*		165,000			2,188,108
					5,214,155
Machinery – 4.6%
Estun Automation Co. Ltd.*		300,000			1,369,322
Hangzhou Oxygen Plant Group Co. Ltd..*		100,093			445,660
Han’s Laser Technology Industry Group Co. Ltd.*		70,000			458,306
Shenzen Inovance Technology Co. Ltd.*		90,000			1,285,297
Techtronic Industries Co. Ltd.		85,000			1,214,934
Zoomlion Heavy Industry Science & Technology Co. Ltd.		650,000			779,950
					5,553,469
Metals & Mining – 4.3%
Angang Steel Co. Ltd.*		2,200,000			897,935
China Molybdenum Co. Ltd.*		1,302,000			851,888
Ganfeng Lithium Co. Ltd.		170,000			2,036,086
Zijin Mining Group Co. Ltd.*		1,200,000			1,359,556
					5,145,465
Pharmaceuticals – 0.8%
Jiangsu Hengrui Medicine Co. Ltd.		55,033			937,618
Real Estate Management & Development – 5.1%
China Resources Land Ltd.		150,000			618,130
China Resources Mixc Lifestyle Services Ltd.*		201,538			934,575
CIFI Hldgs. Group Co. Ltd.		2,042,911			1,731,171
Longfor Group Hldgs. Ltd.		300,000			1,754,833

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis China Opportunities Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
Wharf Real Estate Investment Co. Ltd.*		200,000		$	1,039,414
					6,078,123
Semiconductors & Semiconductor Equipment – 4.0%
Macronix International Co. Ltd.*		500,000			755,454
Taiwan Semiconductor Manufacturing Co. Ltd.		105,000			1,986,334
Xinyi Solar Hldgs. Ltd.		800,000			2,097,749
					4,839,537
Software – 2.1%
Ming Yuan Cloud Group Hldgs. Ltd.*		107,000			658,959
Weimob, Inc.*		1,000,000			1,802,696
					2,461,655
Specialty Retail – 2.9%
China Tourism Group Duty Free Corp. Ltd.		40,000			1,731,304
China Yongda Automobile Services Hldg. Ltd.*		550,000			912,025
Zhongsheng Group Hldgs. Ltd.*		110,000			785,761
					3,429,090
Technology Hardware, Storage & Peripherals – 0.8%
Xiaomi Corp.*		240,000			1,020,061
Textiles, Apparel & Luxury Goods – 3.6%
Li Ning Co. Ltd.		430,000			2,958,877
Shenzhou International Group Hldgs. Ltd.*		70,000			1,371,869
					4,330,746
Transport Infrastructure – 0.6%
Beijing Capital International Airport Co. Ltd.*		800,000			667,718
Utilities — Gas – 0.7%
Kunlun Energy Co. Ltd.		850,000			736,674
Total Equities
(Cost: $72,231,639)				$	121,753,101
Total Investments – 101.4%
(Cost: $72,231,639)				$	121,753,101
Other Liabilities Less Assets – (1.4)%					(1,728,504)
Net Assets — 100%				$	120,024,597

a Certain securities were fair valued under the discretion of the board of trustees. (See Note 2)

* Non-income producing security during the period ended December 31, 2020

ADS — American depositary share

COUNTRY ALLOCATION (As a Percentage of Net Assets) (unaudited)
China ( Includes the People’s Republic of China, Taiwan and Hong Kong)					101.4%

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis International Opportunities Fund

Schedule of Investments(a) December 31, 2020

	Shares		Value
Equities – 97.7%
Australia – 3.6%
Codan Ltd.		110,500		$	954,077
Evolution Mining Ltd.		1,747,400			6,724,614
IDP Education Ltd.		262,500			4,023,509
					11,702,200
Belgium – 0.6%
UnifiedPost Group SA*		68,600			2,095,040
Canada – 5.9%
ATS Automation Tooling Systems, Inc.*		113,700			1,996,382
BRP, Inc.		47,200			3,118,115
Cargojet, Inc.		12,700			2,143,406
Kinaxis, Inc.*		18,100			2,564,344
Parex Resources, Inc.*		225,524			3,104,078
Ritchie Bros. Auctioneers, Inc.		90,600			6,297,657
					19,223,982
China – 5.0%
Kingdee International Software Group Co. Ltd.*		1,034,700			4,224,192
Pharmaron Beijing Co. Ltd.		538,900			9,110,973
Venus MedTech Hangzhou, Inc.*		311,800			3,182,089
					16,517,254
Denmark – 1.8%
Pandora A/S		51,400			5,752,577
Finland – 2.5%
Metso Outotec Oyj*		821,036			8,249,275
France – 1.0%
SPIE SA*		145,500			3,172,170
Germany – 3.5%
Aurelius Equity Opportunities SE*		113,323			2,414,655
KION Group AG		23,700			2,055,227
Shop Apotheke Europe NV*		21,089			3,817,969
Westwing Group AG*		77,600			3,139,169
					11,427,020
Israel – 2.0%
Fiverr International Ltd.*		34,200			6,672,420
Japan – 35.4%
BASE, Inc.*		104,700			9,909,657
BayCurrent Consulting, Inc.		82,300			14,443,039
Capcom Co. Ltd.		77,200			5,006,627
IR Japan Hldgs. Ltd.		62,700			10,045,426
ITmedia, Inc.		70,300			1,502,092
J-Stream, Inc.*		38,700			1,999,554

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis International Opportunities Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
JMDC, Inc.*		65,600		$	3,724,678
Kobe Bussan Co. Ltd.		109,400			3,361,315
Koei Tecmo Hldgs. Co. Ltd.*		85,200			5,201,346
Kusuri no Aoki Hldgs. Co. Ltd.		28,200			2,452,558
M&A Capital Partners Co. Ltd.*		160,800			9,220,373
Medley, Inc.*		184,700			8,135,584
MedPeer, Inc.*		87,500			6,934,990
Oisix ra daichi, Inc.*		57,700			1,747,323
Open House Co. Ltd.		95,500			3,513,250
PLAID, Inc.*		31,200			1,122,541
SHIFT, Inc.*		19,700			2,729,914
Sushiro Global Hldgs. Ltd.		463,600			17,784,582
TechMatrix Corp.		151,200			3,145,117
Tsubaki Nakashima Co. Ltd.		141,400			1,541,384
Wacom Co. Ltd.*		265,900			2,230,542
					115,751,892
Netherlands – 6.9%
Alfen NV*		82,500			8,313,452
ASM International NV		8,800			1,920,264
BE Semiconductor Industries NV		58,100			3,488,832
Constellium SE*		625,200			8,746,548
					22,469,096
Norway – 3.8%
Kahoot AS*		536,400			5,924,172
Nordic Semiconductor ASA*		398,600			6,403,670
					12,327,842
Sweden – 12.9%
Avanza Bank Hldg. AB*		130,300			3,690,007
BHG Group AB*		410,000			8,950,698
Embracer Group AB*		282,700			6,727,553
Indutrade AB*		66,000			1,412,818
Sinch AB*		112,400			18,279,068
Stillfront Group AB*		265,420			3,221,197
					42,281,341
United Kingdom – 12.8%
Blue Prism Group PLC*		166,784			3,916,653
Dunelm Group PLC		134,100			2,220,122
EasyJet PLC*		312,700			3,548,737
Endava PLC ADS*		44,900			3,446,075
Games Workshop Group PLC		27,300			4,179,998
Intermediate Capital Group PLC		399,800			9,406,808
Marks & Spencer Group PLC*		2,237,600			4,150,254
Pets at Home Group PLC		696,263			3,960,882
Spirent Communications PLC		497,000			1,796,758

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis International Opportunities Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
Taylor Wimpey PLC*		2,397,300		$	5,422,364
					42,048,651
Total Equities
(Cost: $186,015,762)				$	319,690,760
Total Investments – 97.7%
(Cost: $186,015,762)				$	319,690,760
Other Assets Less Liabilities – 2.3%					7,663,627
Net Assets – 100%				$	327,354,387

a Certain securities were fair valued under the discretion of the Board of Trustees. (See Note 2)

* Non-income producing security during the period ended December 31, 2020

ADS — American depositary share

Sector Allocations (As A Percentage of Net Assets) (unaudited)
Communication Services					9.0%
Consumer Discretionary					22.9%
Consumer Staples					1.8%
Energy					0.9%
Financials					7.6%
Healthcare					9.5%
Industrials					19.3%
Information Technology					20.8%
Materials					4.7%
Real Estate					1.2%

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis Emerging Markets Fund

Schedule of Investments(a) December 31, 2020

	Shares		Value
Equities – 98.8%
Argentina – 1.2%
Despegar.com Corp.*		9,800		$	125,538
Australia – 1.9%
IDP Education Ltd.		13,000			199,260
Brazil – 6.9%
Afya Ltd.*		5,200			131,560
Arco Platform Ltd.*		3,700			131,313
B2W — Companhia Digital*		12,356			179,862
Lojas Renner SA		17,600			147,531
TOTVS SA		27,900			154,266
					744,532
Canada – 2.5%
Lundin Mining Corp.		17,000			150,915
Parex Resources, Inc.*		8,400			115,616
					266,531
Chile – 3.3%
Falabella SA		51,000			188,783
GeoPark Ltd.		12,500			162,375
					351,158
China – 17.2%
China Isotope & Radiation Corp.		41,200			143,112
Chongqing Brewery Co. Ltd.		6,500			118,378
Dada Nexus Ltd. ADS*		9,900			361,350
Guangdong Marubi Biotechnology Co. Ltd.		9,800			78,359
Jiangsu Hengli Hydraulic Co. Ltd.		9,052			156,614
Kingsoft Cloud Hldgs. Ltd. ADS*		2,800			121,940
Li Ning Co. Ltd.		8,500			58,489
Shanghai Weaver Network Co. Ltd.		6,296			97,354
Venus MedTech Hangzhou, Inc.*		13,000			132,672
Weimob, Inc.*		66,000			118,978
Winning Health Technology Group Co. Ltd.		30,360			81,329
Wolong Electric Group Co. Ltd.		45,500			108,680
Yantai Jereh Oilfield Services Group Co. Ltd.		29,900			160,342
Yijiahe Technology Co. Ltd.		7,120			104,483
					1,842,080
Czech Republic – 1.3%
TCS Group Hldg. PLC		4,200			138,186
France – 1.7%
Gaztransport & Technigaz SA		1,850			179,218

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis Emerging Markets Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
Greece – 1.3%
Greek Organization of Football Prognostics SA		10,400		$	139,042
Hong Kong – 0.8%
SUNeVision Hldgs. Ltd.		100,000			91,022
India – 11.3%
Affle India Ltd.*		6,500			337,255
Amber Enterprises India Ltd.*		3,900			126,002
ESAB India Ltd.		4,025			104,867
MakeMyTrip Ltd.*		4,000			118,120
Navin Fluorine International Ltd.		3,900			139,700
Route Mobile Ltd.*		11,600			174,411
Varun Beverages Ltd.*		17,275			216,983
					1,217,338
Indonesia – 4.7%
PT Bank BTPN Syariah Tbk		340,300			90,895
PT Industri Jamu dan Farmasi Sido Muncul Tbk		1,576,200			90,330
PT Mark Dynamics Indonesia Tbk		1,600,000			95,658
PT Mitra Adiperkasa Tbk*		2,363,900			133,023
PT Sarana Menara Nusantara Tbk		1,427,800			97,614
					507,520
Malaysia – 1.3%
My E.G. Services Bhd*		300,000			143,597
Mexico – 2.4%
Alsea SAB de CV*		86,900			113,060
Prologis Property Mexico SA de CV		65,044			145,911
					258,971
Philippines – 1.0%
Wilcon Depot, Inc.		316,000			111,443
Poland – 1.2%
Dino Polska SA*		1,600			124,086
Russia – 1.2%
HeadHunter Group PLC ADS		4,300			130,075
South Africa – 1.7%
Clicks Group Ltd.		4,980			85,628
Distell Group Hldgs. Ltd.*		14,800			95,719
					181,347
South Korea – 17.3%
AfreecaTV Co. Ltd.		2,000			111,528
Douzone Bizon Co. Ltd.		1,319			126,374
ITM Semiconductor Co. Ltd.*		2,880			151,056
KINX, Inc.		2,520			166,914

See accompanying notes to financial statements.

TABLE OF CONTENTS

Oberweis Emerging Markets Fund (continued)

Schedule of Investments(a) December 31, 2020

	Shares		Value
Korea Investment Hldgs. Co. Ltd.		1,750		$	127,520
LEENO Industrial, Inc.		1,705			212,041
NHN KCP Corp.		3,505			221,244
Nice Information Service Co. Ltd.		7,692			175,940
POSCO Chemical Co. Ltd.		2,186			209,899
Seegene, Inc.		310			55,170
Tokai Carbon Korea Co. Ltd.		1,574			181,718
Wonik Ips Co. Ltd.*		2,860			116,708
					1,856,112
Sweden – 1.5%
Medicover AB*		7,900			158,353
Switzerland – 1.8%
Wizz Air Hldgs. PLC*		3,109			194,101
Taiwan – 14.6%
Airtac International Group		6,000			192,844
ASPEED Technology, Inc.		2,000			122,329
Chailease Hldg. Co. Ltd.		15,873			95,008
Chief Telecom, Inc.*		11,000			139,023
Innodisk Corp.		18,340			108,586
LandMark Optoelectronics Corp.*		20,000			201,734
M31 Technology Corp.		30,000			361,412
momo.com, Inc.*		4,000			90,774
Sinbon Electronics Co. Ltd.		18,000			138,762
Taiwan FamilyMart Co. Ltd.		12,000			111,945
					1,562,417
Thailand – 0.7%
Netbay PLC		76,000			70,496
Total Equities
(Cost: $7,406,376)				$	10,592,423
Rights – 0.1%
South Korea – 0.1%
POSCO Chemical Co. Ltd.*		521			14,599
Total Rights
(Cost: $0)				$	14,599
Total Investments – 98.9%
(Cost: $7,406,376)				$	10,607,022
Other Assets Less Liabilities – 1.1%					120,716
Net Assets – 100%				$	10,727,738

a Certain securities were fair valued under the discretion of the Board of Trustees. (See Note 2)

* Non-income producing security during the period ended December 31, 2020

ADS — American depositary share

See accompanying notes to financial statements.

TABLE OF CONTENTS

THE OBERWEIS FUNDS

Statements of Assets and Liabilities December 31, 2020

	Micro-Cap Fund			Small-Cap Opportunities Fund			Global Opportunities Fund
ASSETS
Investment securities at valuea		$	75,768,547		$	16,716,975		$	63,304,234
Cash			1,663,548			107,506			—
Receivable from fund shares sold			2,767			2,611			33,474
Dividends and interest receivable			7,321			3,749			29,311
Prepaid expenses			20,909			13,070			17,589
Total Assets			77,463,092			16,843,911			63,384,608
LIABILITIES
Payable to custodian bank			—			—			584,070
Payable for fund shares redeemed			5,966			1,050			30,430
Payable for securities purchased			798,055			171,447			—
Payable to advisor (see note 3)			63,731			9,411			43,171
Payable to distributor			9,389			1,642			9,231
Accrued expenses			38,990			27,555			42,719
Total Liabilities			916,131			211,105			709,621
NET ASSETS		$	76,546,961		$	16,632,806		$	62,674,987
NET ASSETS
Investor Class		$	45,344,746		$	7,766,886		$	45,565,500
Institutional Class			31,202,215			8,865,920			17,109,487
Total		$	76,546,961		$	16,632,806		$	62,674,987
SHARES OUTSTANDING
(shares of beneficial interest issued and outstanding, respectively, unlimited number of shares authorized with no par value)
Investor Class			1,558,493			424,654			1,248,150
Institutional Class			1,062,565			479,033			464,079
Total			2,621,058			903,687			1,712,229
NET ASSET VALUE
Investor Class, offering price and redemption price		$	29.10		$	18.29		$	36.51
Institutional Class, offering price and redemption price		$	29.36		$	18.51		$	36.87
ANALYSIS OF NET ASSETS
Capital		$	48,155,520		$	10,925,027		$	38,433,719
Accumulated earnings			28,391,441			5,707,779			24,241,268
Net assets		$	76,546,961		$	16,632,806		$	62,674,987
a Investment securities at cost		$	47,329,311		$	11,605,119		$	39,469,431

See accompanying notes to the financial statements.

TABLE OF CONTENTS

THE OBERWEIS FUNDS

Statements of Assets and Liabilities December 31, 2020 (continued)

	China Opportunities Fund			International Opportunities Fund			Emerging Markets Fund
ASSETS
Investment securities at valuea		$	121,753,101		$	319,690,760		$	10,607,022
Cash			—			7,440,868			202,787
Receivable from fund shares sold			10,125			86,591			—
Receivable from securities sold			222,510			300,308			—
Dividends and interest receivable			25,794			836,722			14,700
Prepaid expenses			23,298			38,821			6,723
Total Assets			122,034,828			328,394,070			10,831,232
LIABILITIES
Payable to custodian bank			689,930			—			—
Payable for fund shares redeemed			129,688			261,201			—
Payable for securities purchased			977,262			291,128			—
Payable to advisor (see note 3)			122,339			289,847			80
Payable to distributor			20,106			65,821			156
Accrued expenses			70,906			131,686			103,258
Total Liabilities			2,010,231			1,039,683			103,494
NET ASSETS		$	120,024,597		$	327,354,387		$	10,727,738
NET ASSETS
Investor Class		$	98,527,383		$	327,354,387		$	789,281
Institutional Class			21,497,214			—			9,938,457
Total		$	120,024,597		$	327,354,387		$	10,727,738
SHARES OUTSTANDING
(shares of beneficial interest issued and outstanding, respectively, unlimited number of shares authorized with no par value)
Investor Class			5,699,921			10,384,468			57,158
Institutional Class			1,233,805			—			714,948
Total			6,933,726			10,384,468			772,106
NET ASSET VALUE
Investor Class, offering price and redemption price		$	17.29		$	31.52		$	13.81
Institutional Class, offering price and redemption price		$	17.42		$	—		$	13.90
ANALYSIS OF NET ASSETS
Capital		$	64,813,971		$	210,107,050		$	7,293,624
Accumulated earnings			55,210,626			117,247,337			3,434,114
Net assets		$	120,024,597		$	327,354,387		$	10,727,738
a Investment securities at cost		$	72,231,639		$	186,015,762		$	7,406,376

See accompanying notes to the financial statements.

TABLE OF CONTENTS

THE OBERWEIS FUNDS

Statements of Operations Year Ended December 31, 2020

	Micro-Cap Fund			Small-Cap Opportunities Fund
INVESTMENT INCOME
Dividends		$	220,325		$	51,741
Total investment income			220,325			51,741
EXPENSES
Investment advisory fees (see note 3)			369,513			50,557
Management fees (see note 3)			246,342			50,557
Distribution fees and shareholder services (see note 3)			89,730			15,257
Transfer agent fees and expenses			68,312			26,334
Custodian fees and expenses			10,518			5,275
Accounting services fees			35,531			29,738
Federal and state registration fees			38,322			32,444
Audit fees			16,503			16,486
Other			37,943			13,979
Total expenses before reimbursed expenses			912,714			240,627
Earnings credit (see note 6)			(2,882)			(1,072)
Expense reimbursement (see note 3)			—			(59,987)
Total expenses			909,832			179,568
NET INVESTMENT LOSS			(689,507)			(127,827)
NET REALIZED AND UNREALIZED GAINS (LOSSES) FROM INVESTMENTS
Net realized gains on investment transactions			196,695			1,129,773
Change in net unrealized appreciation/ depreciation on investments			16,794,544			3,466,685
Net realized /unrealized gains on investments			16,991,239			4,596,458
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS		$	16,301,732		$	4,468,631

See accompanying notes to the financial statements.

TABLE OF CONTENTS

THE OBERWEIS FUNDS

Statements of Operations Year Ended December 31, 2020 (continued)

	Global Opportunities Fund			China Opportunities Fund			International Opportunities Fund			Emerging Markets Fund
INVESTMENT INCOME:
Dividendsa		$	182,340		$	830,378		$	2,275,397		$	102,512
Total investment income			182,340			830,378			2,275,397			102,512
EXPENSES:
Investment advisory fees (see note 3)			208,446			1,225,007			3,346,730			104,189
Management fees (see note 3)			185,285			—			—			—
Distribution fees and shareholder services (see note 3)			85,147			202,905			669,346			1,434
Transfer agent fees and expenses			49,865			129,010			376,809			24,044
Custodian fees and expenses			28,788			132,878			306,478			65,619
Accounting services fees			37,859			63,504			117,579			35,976
Federal and state registration fees			32,636			34,979			27,598			32,117
Audit fees			21,002			20,994			20,986			20,986
Other			29,524			56,895			151,863			12,090
Total expenses before reimbursed expenses			678,552			1,866,172			5,017,389			296,455
Earnings credit (see note 6)			(2,665)			(1,839)			(20,088)			(636)
Expense reimbursement (see note 3)			—			—			(713,556)			(169,359)
Total Expenses			675,887			1,864,333			4,283,745			126,460
NET INVESTMENT LOSS			(493,547)			(1,033,955)			(2,008,348)			(23,948)
NET REALIZED AND UNREALIZED GAINS (LOSSES) FROM INVESTMENTS:
Net realized gains on investment transactions			5,915,376			17,261,326			54,354,028			1,204,000
Net realized gains (losses) on foreign currency transactions			(3,506)			(1,353)			(68,493)			5,834
Net realized gains on investments and foreign currency transactions			5,911,870			17,259,973			54,285,535			1,209,834
Change in net unrealized appreciation/ depreciation on investments and translation of assets and liabilities denominated in foreign currencies			17,113,209			28,837,044			68,435,586			1,997,255
Net realized /unrealized gains on investments and foreign currencies			23,025,079			46,097,017			122,721,121			3,207,089
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS		$	22,531,532		$	45,063,062		$	120,712,773		$	3,183,141

Dividends are net of foreign withholding tax of $18,771, $55,071, $213,762, and $17,065 for the Global Opportunities Fund, China Opportunities Fund, International Opportunities Fund, and Emerging Markets Fund respectively.

See accompanying notes to the financial statements.

TABLE OF CONTENTS

THE OBERWEIS FUNDS

Statements of Changes in Net Assets

	Micro-Cap Fund
	Year Ended December 31, 2020			Year Ended December 31, 2019
FROM OPERATIONS
Net investment loss		$	(689,507)		$	(706,980)
Net realized gains on investment transactions			196,695			1,526,728
Change in net unrealized appreciation/depreciation on investments			16,794,544			13,511,984
Net increase in net assets resulting from operations			16,301,732			14,331,732
FROM CAPITAL SHARE TRANSACTIONS
Investor Class
Proceeds from sale of shares			3,637,401			9,676,418
Redemption of shares (see note 5)			(14,654,234)			(27,287,756)
Net decrease from investor class share transactions			(11,016,833)			(17,611,338)
Institutional Class
Proceeds from sale of shares			919,305			18,429,262
Redemption of shares (see note 5)			(7,199,994)			(5,155,907)
Net increase (decrease) from institutional class share transactions			(6,280,689)			13,273,355
Redemption fees (see note 5)			2,917			6,594
Net decrease in net assets resulting from capital share transactions			(17,294,605)			(4,331,389)
Total increase (decrease) in net assets			(992,873)			10,000,343
NET ASSETS
Beginning of year			77,539,834			67,539,491
End of year		$	76,546,961		$	77,539,834
TRANSACTIONS IN SHARES
Investor Class
Shares sold			179,585			450,856
Less shares redeemed			(698,871)			(1,262,621)
Net decrease from investor class share transactions			(519,286)			(811,765)
Institutional Class
Shares sold			43,937			821,535
Less shares redeemed			(355,588)			(229,559)
Net increase (decrease) from institutional class share transactions			(311,651)			591,976
Net decrease from capital share transactions			(830,937)			(219,789)

See accompanying notes to financial statements.

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Statements of Changes in Net Assets (continued)

	Small-Cap Opportunities Fund
	Year Ended December 31, 2020			Year Ended December 31, 2019
FROM OPERATIONS
Net investment loss		$	(127,827)		$	(93,178)
Net realized gains on investment transactions			1,129,773			689,390
Change in net unrealized appreciation/depreciation on investments			3,466,685			1,859,667
Net increase in net assets resulting from operations			4,468,631			2,455,879
FROM DISTRIBUTIONS
Distributions to shareholders
Investor Class			(303,928)			(182,129)
Institutional Class			(345,259)			(165,161)
Net decrease in net assets from distributions			(649,187)			(347,290)
FROM CAPITAL SHARE TRANSACTIONS
Investor Class
Proceeds from sale of shares			300,236			150,627
Proceeds from reinvestment of distributions			253,557			153,834
Redemption of shares (see note 5)			(565,249)			(617,320)
Net decrease from investor class share transactions			(11,456)			(312,859)
Institutional Class
Proceeds from sale of shares			1,144,055			208,229
Proceeds from reinvestment of distributions			233,987			143,919
Redemption of shares (see note 5)			(285,226)			(253,831)
Net increase from institutional class share transactions			1,092,816			98,317
Redemption fees (see note 5)			475			5
Net increase (decrease) in net assets resulting from capital share transactions			1,081,835			(214,537)
Total increase in net assets			4,901,279			1,894,052
NET ASSETS
Beginning of year			11,731,527			9,837,475
End of year		$	16,632,806		$	11,731,527
TRANSACTIONS IN SHARES
Investor Class
Shares sold			22,282			10,835
Shares issued in reinvestment of distributions			13,728			10,698
Less shares redeemed			(36,849)			(44,001)
Net decrease from investor class share transactions			(839)			(22,468)
Institutional Class
Shares sold			98,477			15,223
Shares issued in reinvestment of distributions			12,519			9,919
Less shares redeemed			(19,982)			(18,348)
Net increase from institutional class share transactions			91,014			6,794
Net increase (decrease) from capital share transactions			90,175			(15,674)

See accompanying notes to financial statements.

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Statements of Changes in Net Assets (continued)

	Global Opportunities Fund
	Year Ended December 31, 2020			Year Ended December 31, 2019
From Operations
Net investment loss		$	(493,547)		$	(409,167)
Net realized gains (losses) on investment and foreign currency transactions			5,911,870			(649,051)
Change in net unrealized appreciation/depreciation on investments and foreign currencies			17,113,209			10,432,361
Net increase in net assets resulting from operations			22,531,532			9,374,143
From Distributions
Distributions to shareholders
Investor Class			(2,513,432)			—
Institutional Class			(932,307)			—
Net decrease in net assets from distributions			(3,445,739)			—
From Capital Share Transactions
Investor Class
Proceeds from sale of shares			1,186,951			584,666
Proceeds from reinvestment of distributions			2,288,838			—
Redemption of shares (see note 5)			(3,756,924)			(4,538,262)
Net decrease from investor class share transactions			(281,135)			(3,953,596)
Institutional Class
Proceeds from sale of shares			2,240,433			1,457,054
Proceeds from reinvestment of distributions			692,252			—
Redemption of shares (see note 5)			(1,711,663)			(2,013,578)
Net increase (decrease) from institutional class share transactions			1,221,022			(556,524)
Redemption fees (see note 5)			1,244			427
Net increase (decrease) in net assets resulting from capital share transactions			941,131			(4,509,693)
Total increase in net assets			20,026,924			4,864,450
Net Assets
Beginning of year			42,648,063			37,783,613
End of year		$	62,674,987		$	42,648,063
Transactions in Shares
Investor Class
Shares sold			40,019			25,380
Shares issued in reinvestment of distributions			62,112			—
Less shares redeemed			(143,339)			(196,533)
Net decrease from investor class share transactions			(41,208)			(171,153)
Institutional Class
Shares sold			81,566			63,647
Shares issued in reinvestment of distributions			18,604			—
Less shares redeemed			(61,981)			(88,250)
Net increase (decrease) from institutional class share transactions			38,189			(24,603)
Net decrease from capital share transactions			(3,019)			(195,756)

See accompanying notes to financial statements.

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Statements of Changes in Net Assets (continued)

	China Opportunities Fund
	Year Ended December 31, 2020			Year Ended December 31, 2019
FROM OPERATIONS
Net investment loss		$	(1,033,955)		$	(639,763)
Net realized gains on investment and foreign currency transactions			17,259,973			8,789,080
Change in net unrealized appreciation/depreciation on investments and foreign currencies			28,837,044			17,102,109
Net increase in net assets resulting from operations			45,063,062			25,251,426
FROM DISTRIBUTIONS
Distributions to shareholders
Investor Class			(10,311,587)			(2,479,581)
Institutional Class			(2,129,840)			(467,251)
Net decrease in net assets from distributions			(12,441,427)			(2,946,832)
FROM CAPITAL SHARE TRANSACTIONS
Investor Class
Proceeds from sale of shares			8,261,354			4,480,265
Proceeds from reinvestment of distributions			9,606,661			2,347,314
Redemption of shares (see note 5)			(21,732,415)			(11,082,392)
Net decrease from investor class share transactions			(3,864,400)			(4,254,813)
Institutional Class
Proceeds from sale of shares			3,446,890			7,307,020
Proceeds from reinvestment of distributions			1,876,619			382,078
Redemption of shares (see note 5)			(3,867,154)			(7,939,086)
Net increase (decrease) from institutional class share transactions			1,456,355			(249,988)
Redemption fees (see note 5)			23,467			146,096
Net decrease in net assets resulting from capital share transactions			(2,384,578)			(4,358,705)
Total increase in net assets			30,237,057			17,945,889
NET ASSETS
Beginning of year			89,787,540			71,841,651
End of year		$	120,024,597		$	89,787,540
TRANSACTIONS IN SHARES
Investor Class
Shares sold			553,521			399,070
Shares issued in reinvestment of distributions			561,137			190,683
Less shares redeemed			(1,539,155)			(973,140)
Net decrease from investor class share transactions			(424,497)			(383,387)
Institutional Class
Shares sold			221,745			653,458
Shares issued in reinvestment of distributions			108,726			30,887
Less shares redeemed			(251,302)			(704,497)
Net increase (decrease) from institutional class share transactions			79,169			(20,152)
Net decrease from capital share transactions			(345,328)			(403,539)

See accompanying notes to financial statements.

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Statements of Changes in Net Assets (continued)

	International Opportunities Fund
	Year Ended December 31, 2020			Year Ended December 31, 2019
FROM OPERATIONS
Net investment loss		$	(2,008,348)		$	(812,571)
Net realized gains (losses) on investments and foreign currency transactions			54,285,535			(28,153,929)
Change in net unrealized appreciation/depreciation on investments and foreign currencies			68,435,586			126,930,677
Net increase in net assets resulting from operations			120,712,773			97,964,177
FROM DISTRIBUTIONS
Distributions to shareholders			(1,290,124)			(3,982,313)
Net decrease in net assets from distributions			(1,290,124)			(3,982,313)
FROM CAPITAL SHARE TRANSACTIONS
Proceeds from sale of shares			38,437,961			49,548,735
Proceeds from reinvestment of distributions			1,140,249			3,548,504
Redemption of shares (see note 5)			(155,930,992)			(321,028,173)
Redemption fees (see note 5)			31,009			38,899
Net decrease from capital share transactions			(116,321,773)			(267,892,035)
Total increase (decrease) in net assets			3,100,876			(173,910,171)
NET ASSETS
Beginning of year			324,253,511			498,163,682
End of year		$	327,354,387		$	324,253,511
TRANSACTIONS IN SHARES
Shares sold			1,743,571			2,731,672
Shares issued in reinvestment of distributions			36,095			182,348
Less shares redeemed			(8,080,663)			(17,343,717)
Net decrease from capital share transactions			(6,300,997)			(14,429,697)

See accompanying notes to financial statements.

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Statements of Changes in Net Assets (continued)

	Emerging Markets Fund
	Year Ended December 31, 2020			Year Ended December 31, 2019
FROM OPERATIONS
Net investment loss		$	(23,948)		$	(486)
Net realized gains on investments and foreign currency transactions			1,209,834			49,798
Change in net unrealized appreciation/depreciation on investments and foeign currencies			1,997,255			1,467,078
Net increase in net assets resulting from operations			3,183,141			1,516,390
FROM CAPITAL SHARE TRANSACTIONS
Investor Class
Proceeds from sale of shares			175,609			103,166
Redemption of shares (see note 5)			(182,826)			(42,022)
Net increase (decrease) from investor class share transactions			(7,217)			61,144
Institutional Class
Proceeds from sale of shares			540,546			568,374
Redemption of shares (see note 5)			(957,720)			(614,836)
Net decrease from institutional class share transactions			(417,174)			(46,462)
Redemption fees (see note 5)			522			172
Net increase (decrease) in net assets resulting from capital share transactions			(423,869)			14,854
Total increase in net assets			2,759,272			1,531,244
NET ASSETS
Beginning of year			7,968,466			6,437,222
End of year		$	10,727,738		$	7,968,466
TRANSACTIONS IN SHARES
Investor Class
Shares sold			15,758			11,398
Less shares redeemed			(19,250)			(4,695)
Net increase (decrease) from investor class share transactions			(3,492)			6,703
Institutional Class
Shares sold			48,846			66,768
Less shares redeemed			(93,794)			(67,626)
Net decrease from institutional class share transactions			(44,948)			(858)
Net increase (decrease) from capital share transactions			(48,440)			5,845

See accompanying notes to financial statements.

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Notes to Financial Statements December 31, 2020

1. Description of Organization

Description of business. The Oberweis Funds (the “Trust”) is registered under the Investment Company Act of 1940 as a diversified open-end management investment company. The Trust is authorized to operate numerous Funds under various trading strategies. The Trust consists of seven Funds of which six are in this report: the Oberweis Micro-Cap Fund, the Oberweis Small-Cap Opportunities Fund, the Oberweis Global Opportunities Fund, the Oberweis China Opportunities Fund, the Oberweis International Opportunities Fund, and the Oberweis Emerging Markets Fund (collectively, “the Funds”) are each a series of the Trust. Each Fund in this report except for Oberweis International Opportunities Fund currently offers two classes of shares: Investor Class and Institutional Class. Oberweis International Opportunities Fund offers only Investor Class shares. Each class of shares has identical voting, dividend, liquidation and other rights and the same terms and conditions, except each class may be subject to different class expenses as outlined in the relevant prospectus and each class has exclusive voting rights with respect to matters solely affecting such class.

2. Significant Accounting Policies

The following is a summary of significant accounting policies consistently followed by the Funds. These policies are in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The Funds are each an investment company and follow accounting and reporting guidance under the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 946, “Financial Services – Investment Companies.”

Investment valuation. Investments in securities are stated at value as of the close of the regular trading session on the New York Stock Exchange (“NYSE”) (generally 3 p.m., Central Standard Time). Each listed and unlisted security for which last sale information is regularly reported is valued at the last reported sales price on that day. If there has been no sale on such day, then such security is valued at the current day’s bid price. Any unlisted security for which last sale information is not regularly reported and any listed debt security which has an inactive listed market for which over-the-counter market quotations are readily available is valued at the closing bid price determined on the basis of reasonable inquiry. Restricted securities and any other securities or other assets for which market quotations are not readily available are valued by appraisal at their fair value as determined in good faith under procedures established by and under the general supervision and responsibility of the Board of Trustees. Short-term debt obligations, commercial paper and repurchase agreements are valued on the basis of quoted yields for securities of comparable maturity, quality and type or on the basis of amortized cost.

The Oberweis Global Opportunities Fund, the Oberweis China Opportunities Fund, the Oberweis Emerging Markets Fund and the Oberweis International Opportunities Fund hold foreign equity securities. Foreign securities are fair valued as described in the following circumstances. Generally, trading in foreign securities markets is completed each day at various times prior to the close of the regular trading session of the NYSE. Due to the time differences between the closings of the relevant foreign securities exchanges and the close of the regular trading session of the NYSE for the Funds, the Funds will fair value their foreign investments when it is determined that the market quotations for the foreign investments either are not readily available or are unreliable and, therefore, do not represent fair value. When the fair value prices are utilized, these prices will attempt to

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Notes to Financial Statements December 31, 2020 (continued)

reflect the impact of the U.S. financial markets’ perceptions and trading activities on the Funds’ foreign investments since the last closing prices of the foreign investments were calculated on their primary foreign securities markets or exchanges. For these purposes, the Board of Trustees of the Trust has determined that movements in relevant indices, after the close of the foreign securities exchanges, may demonstrate that market quotations are unreliable, and may trigger fair value pricing for certain securities. Consequently, fair valuation of portfolio securities may occur on a daily basis. In determining fair value prices, the Trust utilizes data furnished by an independent pricing service (and that data draws upon, among other information, the market values of foreign investments). When a Fund uses fair value pricing, the values assigned to the Fund’s foreign investments may not be the quoted or published prices of the investments on their primary markets or exchanges.

Fair Value Measurements. In accordance with Financial Accounting Standards Board (“FASB”) guidance, the Funds utilize the “Fair Value Measurements and Disclosures” to define fair value, set out a framework for measuring fair value, and expand disclosures regarding fair value measurements.

Various inputs are used in determining the value of the Fund’s investments. These inputs are summarized in the three levels listed below:

•

Level 1 – Quoted prices in active markets for identical securities.

•

Level 2 – Other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc).

•

Level 3 – Significant unobservable inputs (including the Fund’s own assumptions in determining the fair value of investments).

The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities. The following is a summary of the inputs used to value the Funds’ net assets as of December 31, 2020:

	Micro-Cap Fund			Small-Cap Opportunities Fund
Level 1 – Equities		$	75,768,547		$	16,716,975
Total Level 1			75,768,547			16,716,975
Level 2			—			—
Level 3			—			—
Total Investments		$	75,768,547		$	16,716,975

	Global Opportunities Fund			China Opportunities Fund			International Opportunities Fund
Level 1 – Equities
Total Asia		$	2,260,465		$	15,824,752		$	6,672,420
Total Australia			—			—			—
Total Europe			1,318,914			—			14,287,664
Total North America			27,897,597			—			19,223,982
Total South America			450,723			—			—
Total Level 1			31,927,699			15,824,752			40,184,066
Level 2 – Equities
Total Asia			12,933,263			105,928,349			132,269,146

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Notes to Financial Statements December 31, 2020 (continued)

	Global Opportunities Fund			China Opportunities Fund			International Opportunities Fund
Total Australia			—			—			11,702,200
Total Europe			18,006,573			—			135,535,348
Total South America			436,699			—			—
Total Level 2			31,376,535			105,928,349			279,506,694
Level 3			—			—			—
Total Investments		$	63,304,234		$	121,753,101		$	319,690,760

	Emerging Markets Fund
Level 1 – Equities
Total Africa		$	181,347
Total Asia			775,821
Total Europe			268,261
Total North America			525,502
Total South America			550,786
Total Level 1			2,301,717
Level 2 – Equities
Total Asia			6,640,803
Total Europe			794,800
Total Australia			199,260
Total South America			670,442
Total Level 2			8,305,305
Level 3			—
Total Investments		$	10,607,022

The Funds’ assets include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation. The pricing service provides fair market valuation on days when the movement in relevant indices exceeds a predetermined threshold.

Foreign Currency Transactions. The accounting records of the Funds are maintained in U.S. dollars. Foreign currency amounts are translated into U.S. dollars at the current rate of exchange to determine the value of investments, assets and liabilities. Purchases and sales of securities, and income and expenses are translated at the prevailing rate of exchange on the respective date of these transactions. The Funds do not isolate that portion of the results of operations resulting from changes in foreign exchange rates on investments from fluctuations arising from changes in market prices of securities held. These fluctuations are included with the net realized and unrealized gains or losses from investments and foreign currencies.

Risks Associated with Foreign Securities and Currencies. Investments in securities of foreign issuers carry certain risks not ordinarily associated with investments in securities of U.S. issuers. These risks include future political and economic developments, and the possible imposition of exchange controls or other foreign governmental laws and restrictions. In addition, with respect to certain countries, there is the possibility of expropriation of assets, confiscatory taxation, political or social instability or diplomatic developments, which could adversely affect investments in those countries.

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Notes to Financial Statements December 31, 2020 (continued)

Certain countries also may impose substantial restrictions on investments in their capital markets by foreign entities, including restrictions on investments in issuers of industries deemed sensitive to relevant national interests. These factors may limit the investment opportunities available and result in a lack of liquidity and a high price volatility with respect to securities of issuers from developing countries.

Fund Share Valuation. Fund shares are sold and redeemed on a continuous basis at net asset value. On each day the NYSE is open for trading, the net asset value per share is determined as of the later of the close of the NYSE or the CBOE by dividing the total value of each Fund’s investments and other assets, less liabilities, by the number of each Fund’s shares outstanding.

Investment Transactions and Investment Income. Investment transactions are accounted for on the trade date (date the order to buy or sell is executed). Dividend income is recorded on the ex-dividend date, except that certain dividends from foreign securities are recorded as soon as the information is available to the Fund, and interest income is recorded on the accrual basis and includes amortization of premium and discount. Realized gains and losses from investment transactions are reported on an identified cost basis. Income and realized and unrealized gains or losses on investments are allocated to each class of shares based on its relative net assets.

Fund Expense Allocations. The Funds account separately for the assets, liabilities and operations of each Fund. Direct expenses of each Fund or class are charged to that Fund or class while general expenses are allocated pro-rata among the Funds based on net assets or other appropriate methods.

Federal Income Taxes and Dividends to Shareholders. It is the policy of the Funds to continue to comply with all requirements of the Internal Revenue Code of 1986, as amended (“the Code”), applicable to regulated investment companies and to distribute substantially all of their taxable income to their shareholders. The Funds have met the requirements of the Code applicable to regulated investment companies for the period ended December 31, 2020. Therefore, no federal income tax provision is required. Income and capital gains of the Funds are determined in accordance with both tax regulations and accounting principles generally accepted in the U.S. (“GAAP”). Such treatment may result in temporary and permanent differences between tax basis earnings and earnings reported for financial statement purposes. These reclassifications, which have no impact on the net asset value of the Funds, are primarily attributable to certain differences in computation of distributable income and capital gains under federal tax rules versus GAAP.

Certain Funds may utilize earnings and profits on redemption of shares as part of the dividends paid deduction.

For the year ended December 31, 2020, permanent book and tax basis differences resulting primarily from differing treatments for net operating losses, foreign currency transactions, passive foreign investment company (“PFIC”) adjustments and the tax practice known as equalization, were identified and reclassified among the components of the Funds’ net assets.

GAAP requires that certain components of net assets be reclassified between financial and tax reporting. These reclassifications have no effect on net assets or net asset value per share. For the year ended December 31, 2020, permanent differences in book and tax accounting have been reclassified to paid in capital and accumulated earnings (loss) as follows:

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Notes to Financial Statements December 31, 2020 (continued)

	Increases/(Decrease)
	Capital			Accumulated Earnings (Loss)
Micro-Cap Fund		$	(615,152)		$	615,152
Global Opportunities Fund			(359,168)			359,168
Small-Cap Opportunities Fund			(51,730)			51,730
China Opportunities Fund			1,676,887			(1,676,887)
International Opportunities Fund			(3,008,256)			3,008,256
Emerging Markets Fund			(81)			81

The tax character of distributions paid during the fiscal year ended December 31, 2020 was as follows:

	Distributions Paid from Ordinary Income			Distributions Paid from Net Long-Term Capital Gains			Total Distributions Paid
Micro-Cap Fund		$	—		$	—		$	—
Global Opportunites Fund			—			3,445,739			3,445,739
Small-Cap Opportunities Fund			—			649,187			649,187
China Opportunities Fund			3,116,458			9,324,969			12,441,427
International Opportunities Fund			1,290,124			—			1,290,124
Emerging Markets Fund			—			—			—

The tax character of distributions paid during the fiscal year ended December 31, 2019 was as follows:

	Distributions Paid from Ordinary Income			Distributions Paid from Net Long-Term Capital Gains			Total Distributions Paid
Micro-Cap Fund		$	—		$	—		$	—
Global Opportunites Fund			—			—			—
Small-Cap Opportunities Fund			—			347,290			347,290
China Opportunities Fund			—			2,946,832			2,946,832
International Opportunities Fund			3,982,313			—			3,982,313
Emerging Markets Fund			—			—			—

As of December 31, 2020, the following Funds had net capital loss carryforwards to offset future net capital gains, if any, to the extent provided by treasury regulations:

	Not Subject to Expiration (Post-Enactment)
	Short-Term			Long-Term
Micro-Cap Fund		$	—		$	—
Global Opportunites Fund			—			—
Small-Cap Opportunities Fund			—			—
China Opportunities Fund			—			—
International Opportunities Fund			8,525,215			—
Emerging Markets Fund			—			—

The Emerging Markets Fund, Global Opportunities Fund and International Opportunities Fund utilized $848,339, $1,841,821 and $53,575,387, respectively, of its capital loss carryforwards during the year ended December 31, 2020.

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Notes to Financial Statements December 31, 2020 (continued)

As of December 31, 2020 the components of accumulated earnings (deficit) on a tax basis were as follows:

	Undistributed ordinary income (deficit)			Undistributed long-term capital gains			Accumulated capital and other losses			Unrealized Appreciation on investments			Unrealized Appreciation / (Depreciation) foreign currency translations and India sales tax
Micro-Cap Fund		$	—		$	294,230		$	—		$	28,097,211		$	—
Global Opportunites Fund			—			484,077			—			23,756,568			623
Small-Cap Opportunities Fund			—			665,720			—			5,042,059			—
China Opportunities Fund			4,018,595			1,847,223			—			49,344,798			10
International Opportunities Fund			—			—			(8,525,215)			125,724,801			47,751
Emerging Markets Fund			3,022			343,838			—			3,155,147			(67,893)

Accumulated capital and other losses consists of timing differences related to wash sales and capital loss carryforwards.

As of December 31, 2020 the cost of investments for federal income tax purposes are as follows:

	Cost of Investments for Federal Tax Purposes			Gross Unrealized Appreciation			Gross Unrealized (Depreciation)			Net Unrealized Appreciation
Micro-Cap Fund		$	47,671,336		$	28,578,830		$	(481,619)		$	28,097,211
Global Opportunities Fund			39,547,666			24,125,461			(368,893)			23,756,568
Small-Cap Opportunities Fund			11,674,916			5,088,834			(46,775)			5,042,059
China Opportunities Fund			72,408,303			49,996,110			(651,312)			49,344,798
International Opportunities Fund			193,965,959			128,472,463			(2,747,662)			125,724,801
Emerging Markets Fund			7,451,875			3,301,679			(146,532)			3,155,147

The Funds have reviewed all open tax years and major jurisdictions and concluded that there are no significant uncertain tax positions that would require recognition in the financial statements. Open tax years are those that are open for exam by taxing authorities and as of December 31, 2020, open federal tax years included the tax years ended 2017 through 2020. The Funds have no examinations in progress and is also not aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months.

Use of estimates. The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results may differ from those estimates.

Indemnifications. Under the Trust’s organizational documents, its present and former Officers and Trustees are indemnified against certain liabilities arising out of the performance of their duties to the Trust. In addition, in the normal course of business, the Trust enters into contracts that provide general indemnifications to other parties. The Trust’s

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Notes to Financial Statements December 31, 2020 (continued)

maximum exposure under these arrangements is unknown as this would involve future claims that may be made against the Trust that have not yet occurred. However, the Trust has not had prior claims or losses pursuant to these contracts and expects the risk of loss to be remote.

3. Transactions with affiliates

The Funds have written agreements with Oberweis Asset Management, Inc. (“OAM”) as the Funds’ investment advisor and manager. Oberweis Securities, Inc. (“OSI”), the Funds’ principal distributor, is an affiliate of OAM.

Investment advisory agreement. Under the Advisory Agreement, OAM provides investment advisory services to the Micro-Cap, Global Opportunities, and Small-Cap Opportunities Funds and pursuant to a separate Management Agreement, OAM provides non-investment advisory management services such as administrative, compliance and accounting services to these Funds. For investment advisory services, the Micro-Cap Fund paid monthly investment advisory fees at an annual rate equal to .60% of average daily net assets. The Global Opportunities Fund paid monthly investment advisory fees at an annual rate equal to .45% of the first $50 million of average daily net assets and .40% of average daily net assets in excess of $50 million. The Small-Cap Opportunities Fund paid monthly investment advisory fees at an annual rate equal to .40% of average daily net assets. For investment advisory and management services, the China Opportunities Fund, the International Opportunities Fund and the Emerging Markets Fund paid monthly investment advisory and management fees at an annual rate equal to 1.25%, 1.25% and 1.25% of average daily net assets, respectively. For the year ended December 31, 2020, the Micro-Cap Fund, Global Opportunities Fund and Small-Cap Opportunities Fund incurred investment advisory fees totaling $369,513, $208,446 and $50,557, respectively. For the year ended December 31, 2020, the China Opportunities Fund, International Opportunities Fund, and Emerging Market Fund incurred investment advisory fees totaling $1,225,007 , $3,346,730 and $104,189, respectively.

Management agreement. For management services and facilities furnished, the Micro-Cap Fund, Global Opportunities Fund, and Small-Cap Opportunities Fund each paid a monthly fee at an annual rate equal to .40% of average daily net assets. For the year ended December 31, 2020, the Micro-Cap Fund, Global Opportunities Fund, and Small-Cap Opportunities Fund incurred management fees totaling $246,342, $185,285, and $50,557, respectively.

Expense reimbursement. OAM is contractually obligated to reduce its investment and management fees or reimburse the Micro-Cap Fund and Global Opportunities Fund Investor Class Shares to the extent that total ordinary operating expenses, as defined, exceed in any one year the following amounts expressed as a percentage of each Fund’s average daily net assets: 1.80% of the first $50 million; plus 1.60% of average daily net assets in excess of $50 million. OAM is contractually obligated to reduce its investment and management fees or reimburse Small-Cap Opportunities Fund, China Opportunities Fund, International Opportunities Fund and Emerging Markets Fund Investor Class Shares to the extent that total ordinary operating expenses, as defined, exceed in any one year 1.55%, 2.24%, 1.60% and 1.75% expressed as a percentage of the Fund’s average daily net assets, respectively. OAM is contractually obligated to reduce its investment and management fees or reimburse the Global Opportunities Fund and Micro-Cap Fund Institutional Class Shares to the extent that total ordinary operating expenses, as

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Notes to Financial Statements December 31, 2020 (continued)

defined, exceed in any one year the following amounts expressed as a percentage of each Fund’s average daily net assets: 1.55% of the first $50 million; plus 1.35% of average daily net assets in excess of $50 million. OAM is contractually obligated to reduce its investment and management fees or reimburse the Small-Cap Opportunities Fund, China Opportunities Fund and Emerging Markets Fund Institutional Class Shares to the extent that total ordinary operating expenses, as defined, exceed in any one year 1.30%, 1.99% and 1.50% expressed as a percentage of the Funds’ average daily net assets, respectively. For the year ended December 31, 2020 OAM reimbursed the Small-Cap Opportunities Fund, the Emerging Markets Fund, and the International Opportunities Fund in the amount of $59,987, $169,359, and $713,556, respectively.

Officers and trustees. Certain officers and trustees of the Trust are also officers and/or directors of OAM and OSI. During the year ended December 31, 2020, the Trust made no direct payments to its officers and paid $125,000 to its unaffiliated trustees.

Distribution and shareholder service agreement. The Funds have a distribution and shareholder services agreement with OSI. For services under the distribution and shareholder services agreement, the Funds pay OSI a fee at the annual rate of .25% of the average daily net assets of Investor Class Shares as compensation for services. For the year ended December 31, 2020, the Micro-Cap Fund, Small-Cap Opportunities Fund, Global Opportunities Fund, China Opportunities Fund, International Opportunities Fund, and Emerging Markets Fund incurred distribution fees totaling $89,730, $15,257, $85,147, $202,905, $669,346, and $1,434, respectively.

Affiliated Commissions. For the year ended December 31, 2020, the Micro-Cap Fund, Global Opportunities Fund, Small-Cap Opportunities Fund, China Opportunities Fund, Emerging Markets Fund and International Opportunities Fund did not execute any security transactions through OSI and therefore did not pay commissions to OSI.

4. Investment transactions

The cost of securities purchased and proceeds from securities sold during the year ended December 31, 2020, other than money market investments, aggregated $55,786,749 and $71,685,712, respectively, for the Micro-Cap Fund, $57,874,471 and $59,699,084, respectively, for the Global Opportunities Fund, $18,946,377 and $18,079,988, respectively, for the Small-Cap Opportunities Fund, $184,917,466 and $198,626,222, respectively, for the China Opportunities Fund, $343,185,884 and $469,432,682, respectively, for the International Opportunities Fund, $10,537,467 and $10,920,196, respectively, for the Emerging Markets Fund. The Funds did not hold government securities during the year ended December 31, 2020.

The Funds may write covered call options. The premiums received provide a partial hedge (protection) against declining prices and enables each Fund to generate a higher return during periods when OAM does not expect the underlying security to make any major price moves in the near future but still deems the underlying security to be, over the long term, an attractive investment for each Fund. The Funds write covered call options for which premiums received are recorded as liabilities and are subsequently adjusted to the current value of the options written. Premiums received from writing options that expire are treated as realized gains. Premiums received from writing options, which are either exercised or closed, are offset against the proceeds received or amount paid on the transaction to

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Notes to Financial Statements December 31, 2020 (continued)

determine realized gains or losses. Amounts recovered for securities litigation are included in the realized gains of the Fund and are recorded when received. The Funds did not write covered call options during the year ended December 31, 2020. .

5. Redemption fee

The Oberweis Funds are designed for long-term investors. To discourage market timers, redemptions of shares of the Micro-Cap Fund, Global Opportunities Fund, and Small-Cap Opportunities Fund within 90 days of purchase are subject to a 1% redemption fee of the total redemption amount and 2% for the China Opportunities Fund, the Emerging Markets Fund and the International Opportunities Fund. The redemption fee is deducted from the redemption proceeds and is retained by the Fund.

The redemption fee is retained by the Funds for the expense they incur in connection with shareholder redemptions. Redemption fees received by the Micro-Cap Fund, Small-Cap Opportunities Fund, Global Opportunities Fund, China Opportunities Fund, International Opportunities Fund, and Emerging Markets Fund were $2,917, $475, $1,244, $23,467, $31,009 and $522, respectively, for the year ended December 31, 2020, and $6,594, $5, $427, $146,096, $38,899 and $172, respectively, for the year ended December 31, 2019.

6. Earnings credits and interest charges

The Trust, as part of the agreement with the Custodian, receives credits against its custodian fees on its uninvested cash balances and is allowed to borrow for temporary purposes. Borrowings are not to exceed 5% of the value of each Fund’s total assets at the time of any such borrowing. Interest on amounts borrowed is calculated at the prime rate and is payable monthly. During the year ended December 31, 2020, the Micro-Cap Fund, Small-Cap Opportunities Fund, Global Opportunities Fund, China Opportunities Fund, International Opportunities Fund, and Emerging Markets Fund received credits of $2,882, $1,072, $2,665, $1,839, $20,088, and $636, respectively. During the year ended December 31, 2020, the Micro-Cap Fund, the Small Cap Opportunities Fund, the Global Opportunities Fund, the China Opportunities Fund, the International Opportunities Fund and the Emerging Markets Fund incurred interest charges of $949, $84, $119, $829, $6,694, and $118 respectively, which is included in custodian fees and expenses in the Statements of Operations.

7. Subsequent events

In early 2020, an outbreak of a novel strain of coronavirus (COVID-19) emerged globally. This coronavirus has resulted in closing of international borders, enhanced health screenings, healthcare service preparation and delivery, quarantines, cancellations, disruptions to supply chains and customer activity, as well as general public concern and uncertainty. The impact of this outbreak has negatively affected the worldwide economy, as well as the economies of individual countries, the financial health of individual companies and the market in general in significant and unforeseen ways. The future impact of COVID-19 is currently unknown, and it may exacerbate other risks that apply to the Funds, including political, social and economic risks. Any such impact could adversely affect the Funds’ performance, the performance of the securities in which the Funds invest and may lead to losses on your investment in each Fund. The ultimate impact of COVID-19 on the financial performance of the Funds’ investments is not reasonably estimable at this time.

The Fund has evaluated subsequent events through the issuance of the financial statements and determined that no events have occurred that require disclosure.

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Financial Highlights

Per share income and capital for a share outstanding throughout each period is as follows:

Investor Class	Micro-Cap Fund
	Years Ended December 31,
	2020			2019			2018			2017			2016
Net asset value at beginning of year		$	22.40		$	18.37		$	25.12		$	22.02		$	17.68
Income (loss) from investment operations:
Net investment lossa			(.26)			(.22)			(.35)			(.32)			(.15)
Net realized and unrealized gains (losses) on investments			6.96			4.25			(2.82)			6.37			4.49
Total from investment operations			6.70			4.03			(3.17)			6.05			4.34
Redemption Feesa			—			—			.03			—			.01
Less distributions:
Distribution from net realized gains on investments			—			—			(3.61)			(2.95)			(.01)
Net asset value at end of year		$	29.10		$	22.40		$	18.37		$	25.12		$	22.02
Total Return (%)			29.91			21.94			(12.30)			27.90			24.60
Ratio/Supplemental Data
Net Assets at end of year (in thousands)		$	45,345		$	46,546		$	53,094		$	92,249		$	67,133
Ratio of gross expenses to average net assets (%)			1.59			1.60			1.57			1.58			1.65
Ratio of net expenses to average net assets (%)b			1.58			1.58			1.55			1.54			1.64
Ratio of net investment loss to average net assets (%)			(1.22)			(1.03)			(1.30)			(1.32)			(.80)
Portfolio turnover rate (%)			92			112			119			91			102

Notes:

a The net investment loss per share data and the redemption fee data were determined using average shares outstanding during the period.

b The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

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Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Institutional Class	Micro-Cap Fund
	Years Ended December 31,									Period Ended December 31,
	2020			2019			2018			2017a
Net asset value at beginning of period		$	22.55		$	18.47		$	25.17		$	23.52
Income (loss) from investment operations:
Net investment lossb			(.21)			(.13)			(.28)			(.18)
Net realized and unrealized gains (losses) on investments			7.02			4.21			(2.84)			4.18
Total from investment operations			6.81			4.08			(3.12)			4.00
Redemption Feesb			—			—			.03			—
Less distributions:
Distribution from net realized gains on investments			—			—			(3.61)			(2.35)
Net asset value at end of period		$	29.36		$	22.55		$	18.47		$	25.17
Total Return (%)			30.20			22.09			(12.07)			16.92d
Ratio/Supplemental Data
Net Assets at end of period (in thousands)		$	31,202		$	30,994		$	14,445		$	9,346
Ratio of gross expenses to average net assets (%)			1.34			1.34			1.33			1.32e
Ratio of net expenses to average net assets (%)c			1.33			1.32			1.32			1.28e
Ratio of net investment loss to average net assets (%)			(.97)			(.61)			(1.05)			(1.04)e
Portfolio turnover rate (%)			92			112			119			91

Notes:

a For the period from May 1, 2017 (commencement of operations) through December 31, 2017.

b The net investment loss per share data and the redemption fee data were determined using average shares outstanding during the period.

c The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

d Not annualized

e Annualized.

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Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Investor Class	Small-Cap Opportunities Fund
	Years Ended December 31,
	2020			2019			2018			2017			2016
Net asset value at beginning of year		$	14.36		$	11.83		$	16.40		$	13.89		$	13.48
Income (loss) from investment operations:
Net investment lossa			(.17)			(.13)			(.18)			(.22)			(.22)
Net realized and unrealized gains (losses) on investments			4.84			3.10			(1.05)			3.77			1.22
Total from investment operations			4.67			2.97			(1.23)			3.55			1.00
Redemption Feesa			—			—			—			—			—
Less distributions:
Distribution from net realized gains on investments			(.74)			(.44)			(3.34)			(1.04)			(.59)
Net asset value at end of year		$	18.29		$	14.36		$	11.83		$	16.40		$	13.89
Total Return (%)			32.47			25.07			(7.23)			25.54			7.38
Ratio/Supplemental Data
Net Assets at end of year (in thousands)		$	7,767		$	6,110		$	5,299		$	7,533		$	9,385
Ratio of gross expenses to average net assets (%)			2.03			2.21			2.13			2.29			2.40
Ratio of net expenses to average net assets (%)b			1.55			1.55			1.55			1.72			2.00
Ratio of net investment loss to average net assets (%)			(1.14)			(.95)			(1.06)			(1.42)			(1.67)
Portfolio turnover rate (%)			147			142			160			142			150

Notes:

a The net investment loss per share data and the redemption fee data were determined using average shares outstanding during the period.

b The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

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Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Institutional Class	Small-Cap Opportunities Fund
	Years Ended December 31,									Period Ended December 31,
	2020			2019			2018			2017a
Net asset value at beginning of period		$	14.49		$	11.90		$	16.44		$	15.20
Income (loss) from investment operations:
Net investment lossb			(.13)			(.10)			(.14)			(.11)
Net realized and unrealized gains (losses) on investments			4.89			3.13			(1.06)			2.39
Total from investment operations			4.76			3.03			(1.20)			2.28
Redemption Feesb			—			—			—			—
Less distributions:
Distribution from net realized gains on investments			(.74)			(.44)			(3.34)			(1.04)
Net asset value at end of period		$	18.51		$	14.49		$	11.90		$	16.44
Total Return (%)			32.80			25.43			(7.05)			14.99d
Ratio/Supplemental Data
Net Assets at end of period (in thousands)		$	8,866		$	5,622		$	4,538		$	3,564
Ratio of gross expenses to average net assets (%)			1.78			1.96			1.88			1.86e
Ratio of net expenses to average net assets (%)c			1.30			1.30			1.30			1.30e
Ratio of net investment loss to average net assets (%)			(.89)			(.69)			(.80)			(.97)e
Portfolio turnover rate (%)			147			142			160			142

Notes:

a For the period from May 1, 2017 (commencement of operations) through December 31, 2017.

b The net investment loss per share data and the redemption fee data were determined using average shares outstanding during the period.

c The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

d Not annualized

e Annualized.

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Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Investor Class	Global Opportunities Fund
	Years Ended December 31,
	2020			2019			2018			2017			2016
Net asset value at beginning of year		$	24.82		$	19.75		$	28.36		$	24.13		$	24.78
Income (loss) from investment operations:
Net investment lossa			(.32)			(.24)			(.20)			(.19)			(.24)
Net realized and unrealized gains (losses) on investments and translation of assets and liabilities denominated in foreign currency			14.13			5.31			(7.09)			8.21			(.14)
Total from investment operations			13.81			5.07			(7.29)			8.02			(.38)
Redemption feesa			—			—			—			—			—
Less distributions:
Distribution from net realized gains on investments			(2.12)			—			(1.32)			(3.79)			(.27)
Net asset value at end of year		$	36.51		$	24.82		$	19.75		$	28.36		$	24.13
Total Return (%)			55.55			25.67			(25.66)			33.30			(1.54)
Ratio/Supplemental Data
Net Assets at end of year (in thousands)		$	45,566		$	32,004		$	28,847		$	47,856		$	44,604
Ratio of gross expenses to average net assets (%)			1.53			1.58			1.52			1.52			1.59
Ratio of net expenses to average net assets (%)b			1.53			1.55			1.50			1.50			1.59
Ratio of net investment loss to average net assets (%)			(1.14)			(1.07)			(.72)			(.67)			(.99)
Portfolio turnover rate (%)			129			120			155			137			126

Notes:

a The net investment loss per share data and the redemption fee data were determined using average shares outstanding during the period.

b The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

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Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Institutional Class	Global Opportunities Fund
	Years Ended December 31,									Period Ended December 31,
	2020			2019			2018			2017a
Net asset value at beginning of period		$	24.99		$	19.84		$	28.41		$	27.42
Income (loss) from investment operations:
Net investment lossb			(.25)			(.18)			(.13)			(.12)
Net realized and unrealized gains (losses) on investments and translation of assets and liabilities denominated in foreign currency			14.25			5.33			(7.12)			4.90
Total from investment operations			14.00			5.15			(7.25)			4.78
Redemption Feesb			—			—			—			—
Less distributions:
Distribution from net realized gains on investments			(2.12)			—			(1.32)			(3.79)
Net asset value at end of period		$	36.87		$	24.99		$	19.84		$	28.41
Total Return (%)			55.94			25.96			(25.48)			17.49e
Ratio/Supplemental Data
Net Assets at end of period (in thousands)		$	17,109		$	10,644		$	8,937		$	7,919
Ratio of gross expenses to average net assets (%)			1.28			1.33			1.28			1.20d
Ratio of net expenses to average net assets (%)c			1.27			1.30			1.25			1.18d
Ratio of net investment loss to average net assets (%)			(.88)			(.78)			(.49)			(.59)d
Portfolio turnover rate (%)			129			120			155			137

Notes:

a For the period from May 1, 2017 (commencement of operations) through December 31, 2017.

b The net investment loss per share data and the redemption fee data were determined using average shares outstanding during the period.

c The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

d Annualized.

e Not annualized.

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Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Investor Class	China Opportunities Fund
	Years Ended December 31,
	2020			2019			2018			2017			2016
Net asset value at beginning of year		$	12.33		$	9.35		$	15.95		$	10.94		$	12.15
Income (loss) from investment operations:
Net investment lossa			(.16)			(.09)			(.10)			(.06)			(.11)
Net realized and unrealized gains (losses) on investments and translation of assets and liabilities denominated in foreign currencies			7.11			3.47			(4.06)			6.07			(1.01)
Total from investment operations			6.95			3.38			(4.16)			6.01			(1.12)
Redemption Feesa			—			.02			—			—			—
Less dividends and distributions:
Distribution from net realized gains on investments			(1.99)			(.42)			(2.44)			(.98)			(.09)
Dividends from net investment income			—			—			—			(.02)			—
Total dividends and distributions			(1.99)			(.42)			(2.44)			(1.00)			(.09)
Net asset value at end of year		$	17.29		$	12.33		$	9.35		$	15.95		$	10.94
Total Return (%)			56.51			36.33			(26.01)			55.05			(9.22)
Ratio/Supplemental Data
Net Assets at end of year (in thousands)		$	98,527		$	75,487		$	60,844		$	107,190		$	91,197
Ratio of gross expenses to average net assets (%)			1.95			1.95			1.91			1.92			1.99
Ratio of net expenses to average net assets (%)b			1.95			1.84			1.86			1.91			1.98
Ratio of net investment loss to average net assets (%)			(1.11)			(.77)			(.68)			(.38)			(.93)
Portfolio turnover rate (%)			192			184			85			97			125

Notes:

a The net investment loss per share data and the redemption fee data were determined using average shares outstanding during the period.

b The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

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Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Institutional Class	China Opportunities Fund
	Years Ended December 31,									Period Ended December 31,
	2020			2019			2018			2017a
Net asset value at beginning of period		$	12.39		$	9.36		$	15.93		$	12.78
Income (loss) from investment operations:
Net investment lossb			(.13)			(.07)			(.06)			(.01)
Net realized and unrealized gains (losses) on investments and translation of assets and liabilities denominated in foreign currencies			7.15			3.50			(4.07)			4.19
Total from investment operations			7.02			3.43			(4.13)			4.18
Redemption feesb			—			.02			—			—
Less dividends and distributions:
Distribution from net realized gains on investments			(1.99)			(.42)			(2.44)			(.98)
Dividends from net investment income			—			—			—			(.05)
Total dividends and distributions			(1.99)			(.42)			(2.44)			(1.03)
Net asset value at end of period		$	17.42		$	12.39		$	9.36		$	15.93
Total return (%)			56.79			36.82			(25.85)			32.87e
Ratio/Supplemental Data
Net Assets at end of period (in thousands)		$	21,497		$	14,301		$	10,998		$	14,087
Ratio of gross expenses to average net assets (%)			1.69			1.70			1.65			1.60d
Ratio of net expenses to average net assets (%)c			1.69			1.59			1.61			1.59d
Ratio of net investment loss to average net assets (%)			(.85)			(.55)			(.42)			(.12)d
Portfolio turnover rate (%)			192			184			85			97

Notes:

a For the period from May 1, 2017 (commencement of operations) through December 31, 2017.

b The net investment loss per share data and the redemption fee data were determined using average shares outstanding during the period.

c The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

d Annualized.

e Not annualized.

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Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Investor Class	International Opportunities Fund
	Years Ended December 31,
	2020			2019			2018			2017			2016
Net asset value at beginning of year		$	19.43		$	16.01		$	25.49		$	20.19		$	21.33
Income (loss) from investment operations:
Net investment income (loss)a			(.16)			(.03)			(.04)			(.04)			.01
Net realized and unrealized gains (losses) on investments and translation of assets and liabilities denominated in foreign currencies			12.37			3.69			(6.30)			8.26			(1.15)
Total from investment operations			12.21			3.66			(6.34)			8.22			(1.14)
Redemption Feesa			—			—			—			—			.01
Less dividends and distributions:
Distribution from net realized gains on investments			—			—			(3.10)			(2.85)			—
Dividends from net investment income			(.12)			(.24)			(.04)			(.07)			(.01)
Total dividends and distributions			(.12)			(.24)			(3.14)			(2.92)			(.01)
Net asset value at end of year		$	31.52		$	19.43		$	16.01		$	25.49		$	20.19
Total return (%)			62.86			22.85			(24.73)			40.77			(5.28)
Ratio/Supplemental Data
Net Assets at end of year (in thousands)		$	327,354		$	324,254		$	498,164		$	905,392		$	708,514
Ratio of gross expenses to average net assets (%)			1.87			1.82			1.77			1.79			1.82
Ratio of net expenses to average net assets (%)(b)			1.60			1.60			1.60			1.60			1.60
Ratio of net investment income (loss) to average net assets (%)			(.75)			(.19)			(.16)			(.18)			.05
Portfolio turnover rate (%)			130			142			145			153			139

Notes:

a The net investment income (loss) per share data and the redemption fee data were determined using average shares outstanding during the period.

b The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

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THE OBERWEIS FUNDS

Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Investor Class	Emerging Markets Fund
	Years Ended December 31,						Period Ended December 31, 2018a
	2020			2019			Period Ended December 31, 2018a
Net asset value at beginning of period		$	9.67		$	7.89		$	10.00
Income (loss) from investment operations:
Net investment (loss)b			(.06)			(.02)			(.01)
Net realized and unrealized gains (losses) on investments and translation of assets and liabilities denominated in foreign currencies			4.20			1.80			(2.10)
Total from investment operations			4.14			1.78			(2.11)
Redemption Feesb			—			—			—
Net asset value at end of period		$	13.81		$	9.67		$	7.89
Total Return (%)			42.81			22.56			(21.10)e
Ratio/Supplemental Data
Net Assets at end of period (in thousands)		$	789		$	587		$	426
Ratio of gross expenses to average net assets (%)			3.79			3.86			3.99d
Ratio of net expenses to average net assets (%)c			1.75			1.75			1.75d
Ratio of net investment loss to average net assets (%)			(.54)			(.21)			(.15)d
Portfolio turnover rate (%)			131			153			111e

Notes:

a For the period from May 1, 2018 (commencement of operations) through December 31, 2018.

b The net investment income (loss) per share data and the redemption fee data were determined using average shares outstanding during the period.

c The ratios in this row reflect the impact, if any, of expense offset arrangements with the advisor, and expense reimbursement form the advisor

d Annualized.

e Not Annualized

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THE OBERWEIS FUNDS

Financial Highlights (continued)

Per share income and capital for a share outstanding throughout each period is as follows:

Institutional Class	Emerging Markets Fund
	Years Ended December 31,						Period Ended December 31, 2018a
	2020			2019			Period Ended December 31, 2018a
Net asset value at beginning of period		$	9.71		$	7.90		$	10.00
Income (loss) from investment operations:
Net investment income (loss)b			(.03)			—			.01
Net realized and unrealized gains (losses) on investments and translation of assets and liabilities denominated in foreign currencies			4.22			1.81			(2.11)
Total from investment operations			4.19			1.81			(2.10)
Redemption Feesb			—			—			—
Net asset value at end of period		$	13.90		$	9.71		$	7.90
Total Return (%)			43.15			22.91			(21.00)e
Ratio/Supplemental Data
Net Assets at end of period (in thousands)		$	9,938		$	7,382		$	6,012
Ratio of gross expenses to average net assets (%)			3.54			3.61			3.74d
Ratio of net expenses to average net assets (%)c			1.50			1.50			1.50d
Ratio of net investment income (loss) to average net assets (%)			(.26)			—			.10d
Portfolio turnover rate (%)			131			153			111e

Notes:

a For the period from May 1, 2018 (commencement of operations) through December 31, 2018.

b The net investment income (loss) per share data and the redemption fee data were determined using average shares outstanding during the period.

c The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian, and expense reimbursement form the advisor

d Annualized.

e Not Annualized

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Trustees of The Oberweis Funds

and the Shareholders of Oberweis Micro-Cap Fund, Oberweis Small-Cap Opportunities Fund, Oberweis Global Opportunities Fund, Oberweis China Opportunities Fund, Oberweis International Opportunities Fund, and Oberweis Emerging Markets Fund

Opinion on the Financial Statements

We have audited the accompanying statements of assets and liabilities of Oberweis Micro-Cap Fund, Oberweis Small-Cap Opportunities Fund, Oberweis Global Opportunities Fund, Oberweis China Opportunities Fund, Oberweis International Opportunities Fund, and Oberweis Emerging Markets Fund, each a series of shares of beneficial interest in The Oberweis Funds, (the “Funds”), including the schedules of investments, as of December 31, 2020, and the related statements of operations for the year then ended, the statements of changes in net assets for each of the years in the two-year period then ended and the financial highlights as noted in the table below, and the related notes (collectively referred to as the “financial statements”).

			Financial Highlights
Investor Class: Micro-Cap Fund Small-Cap Opportunities Fund Global Opportunities Fund China Opportunities Fund International Opportunities Fund			For each of the years in the five-year period ended December 31, 2020
Investor Class: Emerging Markets Fund			For each of the years in the two-year period ended December 31, 2020 and for the period May 1, 2018 (commencement of operations) to December 31, 2018
Institutional Class: Micro-Cap Fund Small-Cap Opportunities Fund Global Opportunities Fund China Opportunities Fund			For each of the years in the three-year period ended December 31, 2020 and for the period May 1, 2017 (commencement of operations) to December 31, 2017
Institutional Class: Emerging Markets Fund			For each of the years in the two-year period ended December 31, 2020 and for the period May 1, 2018 (commencement of operations) to December 31, 2018

In our opinion, the financial statements present fairly, in all material respects, the financial position of the Funds as of December 31, 2020, and the results of their operations for the year then ended, the changes in their net assets for each of the years in the two-year period then ended and their financial highlights as detailed above, in conformity with accounting principles generally accepted in the United States of America.

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING
FIRM (continued)

Basis for Opinion

These financial statements are the responsibility of the Funds’ management. Our responsibility is to express an opinion on the Funds’ financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (“PCAOB”) and are required to be independent with respect to the Funds in accordance with the U.S. federal securities law and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Funds are not required to have, nor were we engaged to perform, an audit of their internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Funds’ internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risk of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our procedures included confirmation of securities owned as of December 31, 2020 by correspondence with the custodian, brokers, or by other appropriate auditing procedures where replies from brokers were not received. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

BBD, LLP

We have served as the auditor of one or more of the Funds in The Oberweis Funds since 2016.

Philadelphia, Pennsylvania
February 24, 2021

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TRUSTEES AND OFFICERS OF THE OBERWEIS FUNDS (unaudited)

Name, Address and Age	Position Held with Fund	Term of Office and Length of Time Served
NONINTERESTED TRUSTEES
Katherine Smith Dedrick (63) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Trustee	Trustee since November, 20041
Gary D. McDaniel (72) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Trustee	Trustee since April, 20041
James G. Schmidt (73) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Trustee	Trustee since December, 20031
INTERESTED TRUSTEES
James D. Oberweis (74) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Trustee2	Trustee since July, 19861
James W. Oberweis (46) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	President	Officer since August, 19963
Patrick B. Joyce (61) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Executive Vice President Chief Compliance Officer and Treasurer	Officer since October, 19943
David I. Covas (45) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Vice President	Officer since August, 20043
Kenneth S. Farsalas (50) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Vice President	Officer since August, 20093
Eric V. Hannemann (47) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Secretary	Officer since August, 20053

1 Unless otherwise noted, each trustee shall serve as a trustee of the Funds until the next meeting of shareholders, if any, called for the purpose of considering the election or re-election of such trustee or of a successor to such trustee, and until the election and qualification of his successor, if any, elected at such meeting, or until such trustee sooner dies, resigns, retires or is removed.

2 James D. Oberweis is an interested trustee of the Funds since he is a shareholder of Oberweis Asset Management, Inc., the Funds’ investment advisor.

3 Elected annually by board of trustees.

The Statement of Additional Information includes additional information about Fund officers and trustees and is available upon request without charge, by calling the Fund at 800-323-6166.

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TRUSTEES AND OFFICERS OF THE OBERWEIS FUNDS

(unaudited) (continued)

Principal Occupation Last Five Years	Number of Portfolios Overseen by Trustee	Other Directorships

President – Smith Dedrick Properties, Inc., 2016 to present; President – KSD Law P.C., 2015 to present; President – KSD Global Consulting, Inc., 2015 to present; Executive Committee Member, Risk Worldwide NZ Ltd., 2011 to 2016; President – Aggressive Publishing, Inc., 2010 to present; Member – Risk Worldwide LLC, 2007 to 2016; Partner – Childress Duffy, Ltd., 2007 to 2015.	7	None
	7	None
Senior Vice President and Chief Financial Officer – Federal Heath Sign Co., May 2003 to December 2019.	7	None

Illinois State Senator, January 2013 to January 2021; Chairman – Oberweis Dairy, Inc. December, 1986 to present.	7	None
President – Oberweis Asset Management, Inc., September, 2001 to present; Portfolio Manager from December, 1995 to present; President and Director – Oberweis Securities, Inc., September, 1996 to present.	Not Applicable	None
Executive Vice President, Secretary and Director – Oberweis Asset Management, Inc., September, 1994 to present; Executive Vice President and Director – Oberweis Securities, Inc. September, 1996 to present.	Not Applicable	None
Vice President – Oberweis Asset Management, Inc., September, 2003 to present.	Not Applicable	None
Vice President – Oberweis Asset Management, Inc., November 2004 to present.	Not Applicable	None
Vice President of Accounting – Oberweis Asset Management, Inc. and Oberweis Securities, Inc., June, 2004 to present.	Not Applicable	None

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THE OBERWEIS FUNDS

Supplemental Information (unaudited)

Qualified Dividend Income

For the year ended December 31, 2020, 4.91% and 94.36% of the dividends paid from net investment income for the China Opportunities and International Opportunities Fund, respectively, are designated as qualified dividend income.

Long-Term Capital Gains

The Global Opportunities Fund, Small-Cap Opportunities Fund and China Opportunities Fund designate $3,445,739, $649,187 and $9,324,969 respectively, as long-term capital gain distribution.

Foreign Taxes Paid

Pursuant to Section 853 of the Internal Revenue Code of 1986, as amended, the China Opportunities Fund, Emerging Markets Fund, International Opportunities Fund and Global Opportunities Fund, respectively, designate $889,184, $119,577, $2,489,159 and $201,111 of income derived from foreign sources and $55,071, $83,027, $213,862 and $18,772 of foreign taxes paid for the period ended December 31, 2020.

Of the ordinary income (including short-term capital gain) distributions made (or to be made) for the year ended December 31, 2020, the proportionate share of income derived from foreign sources and foreign taxes paid attributable to one share of stock are:

	Foreign Source Income			Foreign Taxes Paid
China Opportunities Fund		$	0.1282		$	0.0079
Emerging Markets Fund			0.1549			0.1075
International Opportunities Fund			0.2397			0.0206
Global Opportunities Fund			0.1175			0.0110

Proxy Voting:

The Oberweis Funds has delegated authority to vote proxies related to the Funds’ (Micro-Cap Fund, Small-Cap Opportunities Fund, Global Opportunities Fund, China Opportunities Fund, International Opportunities Fund and Emerging Markets Fund) Portfolio securities to the Funds’ investment advisor, Oberweis Asset Management, Inc. (“OAM”). A description of the policies and procedures that OAM uses in fulfilling this responsibility is available, without charge upon request, by calling 1-800-323-6166. It also appears on www.oberweisfunds.com and in the Funds’ Statement of Additional Information, which can be found on the Securities and Exchange Commission’s (“SEC”) website at http://www.sec.gov. Information on how the Funds voted proxies relating to portfolio securities during the most recent 12 month period ended December 31 is available (1) without charge, upon request, by calling 1-800-323-6166, and (2) on the SEC’s website at http://www.sec.gov.

Availability of Schedules of Portfolio Investments:

The Funds file their complete schedule of portfolio investments with the SEC for the first and third quarter of each fiscal year (March 31 and September 30) on Form NPORT. The Funds’ Forms NPORT are available, without charge, on the SEC’s website at http://www.sec.gov and may be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C. Information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330.

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THE OBERWEIS FUNDS

Supplemental Information (unaudited) (continued)

Approval of Investment Advisory Agreements and Investment Sub-Advisory Agreement

The Investment Advisory Agreement between The Oberweis Funds (the “Trust”) and Oberweis Asset Management, Inc. (“OAM”) with respect to the Micro-Cap Fund, the Global Opportunities Fund and the Small-Cap Opportunities Fund and the Investment Advisory and Management Agreements between the Trust and OAM with respect to the International Opportunities Fund, the China Opportunities Fund and the Emerging Markets Fund (collectively, the “Advisory Agreements”) (the above-noted funds of the Trust are collectively referred to as the “Funds”), and the Investment Sub-Advisory Agreement between OAM and Oberweis Asset Management (Hong Kong) Limited (“OAMHK”), a wholly owned subsidiary of OAM, with respect to the China Opportunities Fund (the “Sub-Advisory Agreement” and together with the Advisory Agreements, the “Agreements”) were last approved by the Board of Trustees of the Trust (the “Board”), including all of the trustees who are not parties to the Agreements or interested persons of any such party (the “independent trustees”), at a meeting on August 20, 2020. The Board, including a majority of the independent trustees, determined that the continuation of the applicable Agreements was in the best interests of each of the Funds.

The Board noted that OAM has been associated with each of the Funds since its inception. The Board recognized that a long-term relationship with a capable, conscientious investment adviser is in the best interests of each Fund, and that shareholders have invested in the Funds knowing that OAM manages the Funds and knowing the investment advisory and management fee schedules.

Nature, Quality and Extent of Services. With respect to the nature, quality and extent of the services provided (i) to the Funds by OAM pursuant to the Advisory Agreements and (ii) to the China Opportunities Fund by OAMHK pursuant to the Sub-Advisory Agreement, the Board considered the background and experience of OAM and OAMHK, the functions performed by OAM and OAMHK and the personnel providing such services, the management capabilities of OAM and OAMHK, the information contained in OAM’s and OAMHK’s Forms ADV, OAM’s financial condition and the compliance reports provided to the Board, and the culture of compliance created by OAM and OAMHK, including the competency of the Trust’s chief compliance officer. The Board also considered the experience, academic background, long tenure, structure and size of the portfolio management/strategy investment teams and their respective roles, the investment process with respect to the types of investments held by the Funds, as well as the honesty and integrity of OAM and OAMHK, and that, in the Board’s experience, OAM and OAMHK personnel are open and forthright with the Board. In addition, the Board considered that OAM and OAMHK are research-oriented firms that conduct extensive research in connection with managing the Funds and also considered the competitive pressure on active management.

The Board reviewed the investment performance of each Fund as compared to a peer universe of funds provided by Broadridge Financial Solutions, Inc. (“Broadridge”), an independent provider (the “Performance Universe”), and as compared to the performance of a relevant market benchmark index. With respect to Fund performance, the Board considered each Fund’s performance over the one-, three-, five- and ten-year periods ended June 30, 2020, as applicable, including any periods of outperformance or underperformance as compared to the performance of the relevant market benchmark index and the Fund’s Performance Universe Average. The Board noted that each Fund,

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THE OBERWEIS FUNDS

Supplemental Information (unaudited) (continued)

except the Micro-Cap Fund and the Small-Cap Opportunities Fund, outperformed its relevant market benchmark index and Performance Universe Average for all periods reviewed. The Board also noted that while the Micro-Cap Fund underperformed relative to its relevant market benchmark index for the one- and three-year periods, the Micro-Cap Fund had outperformed its relevant market benchmark index for the five- and ten-year periods and outperformed the Performance Universe Average for all periods reviewed. In addition, the Board noted that the Small-Cap Opportunities Fund outperformed its relevant market benchmark index for the three-year period. In light of the information provided and the considerations made, the Board concluded that the nature, quality and extent of the services provided to each Fund by OAM and to the China Opportunities Fund by OAMHK have been and are expected to remain satisfactory.

Fees and Expenses. The Board considered the combined investment advisory and management fees charged to each Fund by OAM (the “management fees”) as compared to the management fees of a peer group of funds provided by Broadridge (the “Expense Group”) and the expense ratio(s) of each Fund as compared to the expense ratios of the Expense Group. The Board considered information provided by Broadridge on how it selected the peer funds included in the Expense Group for each Fund and considered certain limitations as to the comparability of the data provided. Based on the information provided, the Board noted that the management fees charged to each Fund, except the International Opportunities Fund, the China Opportunities Fund and the Micro-Cap Fund were the same as, below or near to the median management fee of its Expense Group. The Board also noted that, although the management fees charged to the International Opportunities Fund, the China Opportunities Fund and the Micro-Cap Fund were above the median management fee of the applicable Expense Group, such fees were within a reasonable range of the applicable median. With respect to the investment sub-advisory fees paid to OAMHK relating to the China Opportunities Fund, the Board noted that such fees are paid by OAM and not the China Opportunities Fund.

The Board noted that the expense ratio for each Fund’s Institutional Class, as applicable, was the same as, below or near the median of the expense ratio of its applicable Expense Group. The Board also noted that, although the expense ratio of each Fund’s Investor Class and for the International Opportunities Fund was above the median expense ratio of its applicable Expense Group, such expense ratio was within a reasonable range of the applicable median.

In addition, the Board considered management fees paid to OAM by other clients. With respect to OAM’s other clients, the Board recognized that the mix of services provided to the Funds, the level of responsibility required under the Advisory Agreements with the Funds, and the regulatory and operational requirements with respect to the Funds are greater than OAM’s obligations for similar client accounts, and that the management fees for such accounts are less relevant to the Board’s consideration of the management fees for the Funds because they reflect different competitive forces than those in the mutual fund marketplace. Based on the information provided, the Board concluded that each Fund’s management fees were reasonable and appropriate in amount, given the nature, quality and extent of the services provided and taking into consideration relevant circumstances.

Profitability. With respect to the costs of services provided and profits realized by OAM, the Board considered the management fees received by OAM from each of the Funds as well as the level, quality and expense of OAM’s staff and the services that OAM provides. The Board also considered the explanation from OAM that the profits realized by OAM

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THE OBERWEIS FUNDS

Supplemental Information (unaudited) (continued)

specifically from the relationship with the Funds could not be identified due to the impracticality of expense allocation, noting the difficulty of breaking down profitability related to each Fund versus the other Oberweis Funds and other client accounts because management and personnel time and services are not allocated between the various types of accounts. The Board noted OAM’s belief that, while the profits could not be itemized, the overall profitability of OAM was average and within a reasonable range relative to other investment advisory firms, and considered that OAM has contractually agreed to reimburse the Funds for expenses if their respective expense ratios exceed certain limits. Based on this information, the Board concluded for each Fund that OAM’s profitability was not unreasonable.

Economies of Scale. The Board considered the extent to which economies of scale would be realized as each Fund grows, and whether management fee levels reflect economies of scale for the benefit of Fund shareholders. The Board noted asset capacity constraints for each of the Funds which limit economies of scale and the expense reimbursements made by OAM to many of the Funds. The Board also noted that the investment advisory fee schedule for the Global Opportunities Fund includes a breakpoint designed to share economies of scale with shareholders. The Board concluded that each Fund’s management fees reflect an appropriate recognition of any economies of scale.

Other Benefits to OAM and Its Affiliates. The Board considered the character and amount of other incidental benefits received by OAM and its affiliates from their relationship with the Funds, including the fees received by Oberweis Securities, Inc. (“OSI”), an affiliate of OAM and OAMHK, for distribution services, as applicable, and benefits to OAM and other OAM accounts related to soft dollars generated by the Funds’ brokerage transactions. The Board also noted that during the past year none of the Funds’ brokerage transactions had been placed through OSI.

After due consideration of all of the information and factors deemed relevant by the Board and based upon its own business judgment and the conclusions reached, the Board determined to approve the continuance of the Agreements. The Board, including the independent trustees, did not identify any single factor or group of factors as all-important or controlling, and considered all factors together.

Expense Examples:

As a shareholder of The Oberweis Funds, you may incur two types of costs: (1) transaction costs, including redemption fees and (2) ongoing costs, including management fees; distribution (and/or service) 12b-1 fees; and other Fund expenses. This example is intended to help you understand your ongoing costs (in dollars) of investing in The Oberweis Funds and to compare these costs with the ongoing costs of investing in other mutual funds.

The Example is based on an investment of $1,000 investment at the beginning of the period and held for the entire period.

Actual Expenses:

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THE OBERWEIS FUNDS

Supplemental Information (unaudited) (continued)

account value by $1,000 (for example, an $8,600 account value divided by $1,000=8.6), then multiply the result by the number in the table under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Hypothetical Example for Comparison Purposes:

The second line for each Fund in the table below provides information about hypothetical account values and hypothetical expenses based on each Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund’s actual return.

The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of other funds.

Please note that the expenses shown in the table are meant to highlight your ongoing costs only and do not reflect any transactional costs, such as redemption fees. Therefore, the second line for each Fund in the table is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds. In addition, if these transactional costs were included, your costs would have been higher.

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THE OBERWEIS FUNDS

Supplemental Information (unaudited) (continued)

	Beginning Account Value 7/1/20			Ending Account Value 12/31/20			Expenses Paid During Period 7/1/20 – 12/31/20			Expense Ratio During Period 7/1/20 – 12/31/20
MICRO-CAP FUND
Investor Class
Actual		$	1,000.00		$	1,453.55		$	9.74		1.58%
Hypothetical		$	1,000.00		$	1,017.19		$	8.01		1.58%
Institutional Class
Actual		$	1,000.00		$	1,454.91		$	8.21		1.33%
Hypothetical		$	1,000.00		$	1,018.45		$	6.75		1.33%
SMALL-CAP OPPORTUNITIES FUND
Investor Class
Actual		$	1,000.00		$	1,363.65		$	9.21		1.55%
Hypothetical		$	1,000.00		$	1,017.34		$	7.86		1.55%
Institutional Class
Actual		$	1,000.00		$	1,365.72		$	7.73		1.30%
Hypothetical		$	1,000.00		$	1,018.60		$	6.60		1.30%
GLOBAL OPPORTUNITIES FUND
Investor Class
Actual		$	1,000.00		$	1,364.27		$	9.09		1.53%
Hypothetical		$	1,000.00		$	1,017.44		$	7.76		1.53%
Institutional Class
Actual		$	1,000.00		$	1,365.89		$	7.55		1.27%
Hypothetical		$	1,000.00		$	1,018.75		$	6.44		1.27%
CHINA OPPORTUNITIES FUND
Investor Class
Actual		$	1,000.00		$	1,313.67		$	11.34		1.95%
Hypothetical		$	1,000.00		$	1,015.33		$	9.88		1.95%
Institutional Class
Actual		$	1,000.00		$	1,314.38		$	9.83		1.69%
Hypothetical		$	1,000.00		$	1,016.64		$	8.57		1.69%
INTERNATIONAL OPPORTUNITIES FUND
Investor Class
Actual		$	1,000.00		$	1,459.62		$	9.89		1.60%
Hypothetical		$	1,000.00		$	1,017.09		$	8.11		1.60%

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Trustees and Officers

James D. Oberweis
Trustee

Gary D. McDaniel
Trustee

James W. Oberweis
President

David I. Covas
Vice President

Kenneth S. Farsalas
Vice President

Katherine Smith Dedrick
Trustee

James G. Schmidt
Trustee

Patrick B. Joyce
Executive Vice President
Chief Compliance Officer
Treasurer

Eric V. Hannemann

Secretary

Manager and Investment Advisor

Oberweis Asset Management, Inc.
3333 Warrenville Road, Suite 500, Lisle, IL 60532
800-323-6166
oberweisfunds.com

Distributor

Oberweis Securities, Inc.
3333 Warrenville Road, Suite 500, Lisle, IL 60532
630-577-2300
oberweisfunds.com

Custodian

UMB Bank, n.a.
928 Grand Blvd., Kansas City, MO 64106

Transfer Agent

UMB Fund Services, Inc.
P.O. Box 711, Milwaukee, WI 53201-0711
800-245-7311

Counsel

Vedder Price P.C.
222 North LaSalle Street, Chicago, IL 60601

Independent Registered Public Accounting Firm

BBD LLP
1835 Market Street, 3rd Floor, Philadelphia, PA 19103

The Oberweis Funds

Micro-Cap Fund
Small-Cap Opportunities Fund
Global Opportunities Fund
China Opportunities Fund
International Opportunities Fund
Emerging Markets Fund

800-245-7311

oberweisfunds.com

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Beginning on January 1, 2021, as permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Fund’s shareholder reports will no longer be sent by mail, unless you specifically request paper copies of the reports from the Fund or from your financial intermediary, such as a broker-dealer or bank. Instead, the reports will be made available on www.oberweisfunds.com and you will be notified by mail each time a report is posted and provided with a website link to access the report.

If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the Fund or your financial intermediary electronically by contacting us at 1-800-245-7311.

You may elect to receive all future reports in paper free of charge. You can inform the Fund or your financial intermediary that you wish to continue receiving paper copies of your shareholder reports by contacting us at 1-800-245-7311. Your election to receive reports in paper will apply to all funds held with the fund complex.

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PRESIDENT AND PORTFOLIO MANAGER’S LETTER (unaudited)

Dear Shareholder:

We are pleased to report excellent results for the fund in 2020. The Oberweis International Opportunities Institutional Fund returned 63.65% versus 22.93% for its benchmark, the MSCI World Ex USA Small Cap Growth Index.

Experienced investors know well that virtually all funds, including those with the very best long-term track records, inevitably encounter shorter-term periods of good and bad performance. Style factors, sector constitution, and individual stock selection all play a role. We do not believe a single year says much at all about the stock selection skill of a portfolio manager. 2020 was a fantastic year, with 4072 basis points of excess return. On the other hand, in 2018-2019 our strategy faced headwinds. Despite the statistical irrelevance of short-term metrics, we have found that investors often act on them, with enthusiasm following periods of strong performance and with dismay following challenging ones. That’s normal, it’s human. But it also tends to be wrong.

For example, consider the 2018-2019 period. During this period, investors preferred companies with highly predictable near-term earnings over those with more favorable long-term earnings opportunities. As a result, the types of companies we seek underperformed, leading to what we viewed as a material mispricing. We noted in the 2019 annual report letter: “Over the long term, there is a tradeoff between near-term earnings visibility and long-term earnings potential, but we believe the past two years have rendered the price for favorable long-term earnings growth much less than normal (at least in relation to companies with more certain near-term earnings). Similar to other periods of underperformance in the past, we believe that 2018-2019 is likely to set the stage for a mean reversion to a more normal balance.” This proved spot on, and 2020 turned out to be one of our best years ever in terms of relative and absolute performance. This pattern will inevitably occur again at some point. No one can predict the future, but our experience has been that some of the very best times to buy our strategy often follow periods of challenging performance, with 2020’s exceptional gains following 2018-2019 being a good example.

Fortunately, over the longer term, our portfolio returns are not determined by market sentiment or style biases, but rather by the ability of our holdings to generate healthy cash flows. While many factors influence short-term returns, stock selection skill is the primary determinant of alpha generation over the long term. Good news on that front: Since we began this fund on 3/10/14, we are pleased to report that the fund has cumulatively returned +113.22% vs. 76.88% for the benchmark, resulting in an average annual outperformance of 302 basis points.

The Year in Review

COVID-19 has caused short-term and potentially long-term challenges for the global economy. Early on and before many other investors, we recognized that after an initial shock from the global lockdown, many businesses would adapt. Consumer preferences evolved and many companies found themselves favorably positioned for the new environment. In other words, change happened at a rate far faster than some of the most sophisticated investors ever imagined. At the same time, investors’ expectations for future growth remained at depressed levels, enabling us to find a plentitude of highly mispriced businesses. In many instances, companies reported that COVID was positively accelerating key business metrics by years.

In short, our actively-managed portfolio is not the same as the broader economy. Even if the overall economy is facing issues, as it was in 2020, that does not mean that every company

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PRESIDENT AND PORTFOLIO MANAGER’S LETTER (unaudited) (continued)

in the world is doomed. There will always be idiosyncratic winners. It is simply a matter of separating the wheat from the chaff. This bifurcation was later described as a “K-shaped” recovery.

In this environment we continue to find many opportunities that we believe to be undervalued, probably because of the continuing degree of significant economic change. The objection to investing in any equities just because the overall market might seem fairly valued misses the whole point of active management, which seeks out the undervalued tail-end. Interestingly, we continue to see many people who try hard to engineer reasons not to buy equities despite their favorable long-term return profile.

Internationally, in developed markets, equities may appear to be fully valued based on a superficial P/E analysis. However, based on other metrics such as Free Cash Flow Yield, which we have found to be more predictive, we believe that equities in our universe remain reasonably priced. This is different than in the US, where valuations are more elevated. On a relative basis, JP Morgan found that the US forward twelve-month P/E valuations to be the highest relative to the rest of the world in nearly 20 years.

Some investors are focused on finding value in companies that have been most affected by the COVID-19 pandemic, as share prices for many such companies have cratered. Our approach has been to focus on companies that have thrived in spite of it. Many of our top holdings have continued with unabated growth, often in higher-growth industries and nascent markets with niche offerings in the early stages of adoption. As one might expect, the portfolio is overweight in information technology and consumer discretionary, where such companies are concentrated. The COVID disruption caused rapid changes in business and consumer preferences, and accordingly has led to an abundance of ideas within these sectors. On the other hand, we also own a number of companies that operate in industries that were adversely affected by COVID, but have management teams that discovered ways to rapidly adapt to the new world reality. With expectations depressed, it was easier than normal for such companies to beat earnings estimates.

Outlook

After continued strong performance for the fund, one might again ask: what is next? Looking forward, we are actually more positive on our long-term opportunity set. We believe changes in business and consumption are still being underestimated by the rest of the market. Most economists and market participants fail to fully understand the degree that the pandemic was met by mankind’s ingenuity. Many companies will benefit from significant long-term productivity improvements due to an acceleration in innovation.

Rapid change has brought along even more opportunities at the individual stock level and we expect that to continue. We have conviction that the positive trends we are seeing at the individual company level will continue to offer considerable returns for long-term investors. Indeed, we will not be surprised when we all look back in 20 years and come to understand that COVID was merely an accelerant in the multi-decade shift for the economy through innovation in digitalization, AI, eCommerce, robotics, data analytics, cloud usage and so forth. Covid has led to a bifurcation in the economy — many companies are doing much worse than before and many companies are doing much better than before. Essentially, looking at a normal distribution, the tails have gotten wider. At the right side of the tail, we are finding more companies that are doing even better than before and whose long-term prospects are even more misunderstood and therefore even more undervalued than before.

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PRESIDENT AND PORTFOLIO MANAGER’S LETTER (unaudited) (continued)

Portfolio Highlights

At year end, the fund was invested in 64 stocks in 14 countries. Our top five country weightings (portfolio weighting versus the MSCI World Ex USA Small Cap Growth Index) were Japan (35.1% vs. 26.6%), Sweden (12.9% vs. 10.2%), the United Kingdom (12.8% vs. 15.2%), the Netherlands (6.9% vs. 2.0%), and Canada (5.8% vs. 8.2%). On a sector basis, the portfolio was overweight consumer discretionary (22.8% vs. 14.2%) and underweight consumer staples (1.8% vs. 7.4%).

Top contributors for the year include Sinch AB (SINCH SS), which returned 433.1% and contributed 883 bps; Baycurrent Consulting (6532 JT), which returned 245.9% and contributed 534 bps; and Evolution Gaming Group AB (EVO SS) which returned 141.1% and contributed 423 bps. The largest detractors in 2020 include Air Canada (AC CN), which returned -66.5% and detracted 186 bps. Redrow PLC (RDW LN) which returned -54.3% and detracted 185 bps; and Capita PLC (CPI LN) which returned -69.1% and 167 detracted bps.

On behalf of the entire team at Oberweis, thank you for investing in the Oberweis International Opportunities Institutional Fund. If you have any questions about your account, please contact shareholder services at (800) 245-7311.

Sincerely,


	James W. Oberweis, CFA President			Ralf Scherschmidt Portfolio Manager

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MANAGEMENT DISCUSSION ON FUND PERFORMANCE (unaudited)

Market Environment

Global equities returned 15.90% in 2020, as measured by the MSCI World Index. Global small-caps, as measured by the MSCI World Small-Cap Index, performed similarly, returning 15.96%. Foreign small-caps underperformed U.S. small-caps, as evidenced by the 12.78% return on the MSCI World ex-USA Small-Cap Index. Internationally, small-cap growth equities outperformed small-cap value by 2035 basis points, with the MSCI World ex-USA Small Growth Index returning 22.93% versus only 2.58% for the MSCI World ex-USA Small-Cap Value Index.

Discussion of the International Opportunities Institutional Fund

The International Opportunities Institutional Fund returned 63.65% versus 22.93% for the MSCI World ex-US Small-Cap Growth Index. The portfolio benefitted from stock selection in Japan and Sweden while stock selection in Canada and the U.K. detracted from performance. On a sector level, the portfolio benefitted from stock selection in information technology and consumer discretionary while performance was negatively impacted by stock selection in utilities and financials. At the stock level, Sinch AB (SINCH SS), Baycurrent Consulting (6532 JT), and Evolution Gaming Group AB (EVO SS) were among the top contributors to performance; Air Canada (AC CN), Redrow PLC (RDW LN) and Capita PLC (CPI LN) were among the top detractors. The fund’s portfolio turnover ratio was 134% and the fund’s expense ratio was 1.10%.

For current performance information, please visit www.oberweisfunds.com.

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MANAGEMENT DISCUSSION ON FUND PERFORMANCE

(unaudited) (continued)

Oberweis International Opportunities
Institutional Fund

At December 31, 2020

	Asset Allocation (% of Net Assets)
	Equities					99.1
	Other Assets less Liabilities					0.9

	Top Ten Holdings (% of Net Assets)
	Sinch AB					5.7
	Sushiro Global Hldgs. Ltd.					5.5
	BayCurrent Consulting, Inc.					4.5
	IR Japan Hldgs. Ltd.					3.1
	BASE, Inc.					3.1
	Intermediate Capital Group PLC					2.9
	M&A Capital Partners Co. Ltd.					2.9
	Pharmaron Beijing Co. Ltd.					2.8
	BHG Group AB					2.8
	Constellium SE					2.7

	Top Ten Industries (% of Net Assets)
	Software					9.3
	Entertainment					8.7
	Capital Markets					7.7
	Professional Services					7.6
	Internet & Direct Marketing Retail					7.6
	Information Technology Services					6.6
	Healthcare Technology					5.8
	Hotels, Restaurants & Leisure					5.5
	Metals & Mining					4.8
	Machinery					4.3

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MANAGEMENT DISCUSSION ON FUND PERFORMANCE

(unaudited) (continued)

Average Annual Total Returns1 (for the Periods Ended December 31, 2020)

	1 YR (%)		5 YR (%)		SINCE INCEPTION2 (%)		EXPENSE RATIO3 (%)
OBIIX		63.65		15.44		11.76		1.10
MSCI World Ex-US Small Cap Growth Index		22.93		11.88		8.74

Growth of a $10,000 Investment (from March 10, 2014 to December 31, 2020)

[MISSING IMAGE: tm214310d2-lc_obiixpn.jpg]

2 Since Inception returns are from commencement of operations on 03/10/14 for the Fund.

3 Expense ratio is the total annual net fund operating expense ratio as of 12/31/20. The expense ratio gross of any fee waivers, earnings credit or expense reimbursement was 1.13%.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Schedule of Investmentsa December 31, 2020

	SHARES		VALUE
Equities – 99.1%
Australia – 3.6%
Codan Ltd.		409,999		$	3,540,007
Evolution Mining Ltd.		6,485,340			24,957,884
IDP Education Ltd.		974,149			14,931,419
					43,429,310
Belgium – 0.6%
UnifiedPost Group SA*		254,700			7,778,524
Canada – 6.0%
ATS Automation Tooling Systems, Inc.*		421,975			7,409,177
BRP, Inc.		175,000			11,560,806
Cargojet, Inc.		47,200			7,966,043
Kinaxis, Inc.*		67,146			9,513,009
Parex Resources, Inc.*		837,091			11,521,592
Ritchie Bros. Auctioneers, Inc.		336,300			23,376,403
					71,347,030
China – 5.1%
Kingdee International Software Group Co. Ltd.*		3,839,600			15,675,275
Pharmaron Beijing Co. Ltd.		1,994,500			33,720,235
Venus MedTech Hangzhou, Inc.*		1,157,000			11,807,817
					61,203,327
Denmark – 1.8%
Pandora A/S*		190,722			21,345,193
Finland – 2.6%
Metso Outotec Oyj*		3,047,337			30,617,808
France – 1.0%
SPIE SA*		540,200			11,777,363
Germany – 3.6%
Aurelius Equity Opportunities SE*		420,665			8,963,412
KION Group AG		87,700			7,605,206
Shop Apotheke Europe NV*		78,993			14,300,956
Westwing Group AG*		287,924			11,647,451
					42,517,025
Israel – 2.1%
Fiverr International Ltd.*		126,994			24,776,529

See accompanying notes to the financial statements.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Schedule of Investmentsa December 31, 2020 (continued)

	SHARES		VALUE
Japan – 35.9%
BASE, Inc.*		388,500		$	36,770,788
BayCurrent Consulting, Inc.		305,500			53,612,980
Capcom Co. Ltd.		286,500			18,580,294
IR Japan Hldgs. Ltd.		232,600			37,265,808
ITmedia, Inc.		261,100			5,578,895
J-Stream, Inc.*		143,700			7,424,700
JMDC, Inc.*		246,000			13,967,541
Kobe Bussan Co. Ltd.		405,900			12,471,277
Koei Tecmo Hldgs. Co. Ltd.*		316,100			19,297,480
Kusuri no Aoki Hldgs. Co. Ltd.		104,700			9,105,775
M&A Capital Partners Co. Ltd.*		596,900			34,226,622
Medley, Inc.*		685,400			30,190,197
MedPeer, Inc.*		324,800			25,742,683
Oisix ra daichi, Inc.*		214,100			6,483,569
Open House Co. Ltd.		354,600			13,045,009
PLAID, Inc.*		116,900			4,205,932
SHIFT, Inc.*		73,200			10,143,638
Sushiro Global Hldgs. Ltd.		1,720,900			66,017,014
TechMatrix Corp.		561,200			11,673,542
Tsubaki Nakashima Co. Ltd.		524,900			5,721,872
Wacom Co. Ltd.*		986,800			8,277,919
					429,803,535
Netherlands – 7.0%
Alfen NV*		306,270			30,862,558
ASM International NV		32,895			7,178,078
BE Semiconductor Industries NV		218,044			13,093,268
Constellium SE*		2,320,539			32,464,341
					83,598,245
Norway – 3.8%
Kahoot AS*		1,990,690			21,985,814
Nordic Semiconductor ASA*		1,488,844			23,918,881
					45,904,695
Sweden – 13.1%
Avanza Bank Hldg. AB*		483,700			13,698,053
BHG Group AB*		1,521,644			33,218,967
Embracer Group AB*		1,049,200			24,968,336
Indutrade AB*		245,400			5,253,113
Sinch AB*		416,930			67,803,310
Stillfront Group AB*		986,030			11,966,681
					156,908,460

See accompanying notes to the financial statements.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Schedule of Investmentsa December 31, 2020 (continued)

	SHARES		VALUE
United Kingdom – 12.9%
Blue Prism Group PLC*		619,316		$	14,543,637
Dunelm Group PLC		497,813			8,241,654
EasyJet PLC*		1,160,500			13,170,160
Endava PLC ADS*		166,682			12,792,844
Games Workshop Group PLC		101,267			15,505,344
Intermediate Capital Group PLC		1,483,909			34,914,575
Marks & Spencer Group PLC*		8,304,700			15,403,384
Pets at Home Group PLC		2,584,199			14,700,923
Spirent Communications PLC		1,844,448			6,668,059
Taylor Wimpey PLC*		8,897,600			20,125,148
					156,065,728
Total Equities
(Cost: $700,973,373)				$	1,187,072,772
Total Investments – 99.1%
(Cost: $700,973,373)				$	1,187,072,772
Other Assets Less Liabilities – 0.9%					10,583,220
Net Assets – 100%				$	1,197,655,992

a Certain securities were fair valued under the discretion of the Board of Trustees. (See Note 2)

* Non-income producing security during the period ended December 31, 2020

ADS – American depositary share

See accompanying notes to the financial statements.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Statement of Assets and Liabilities December 31, 2020

Assets:
Investment securities at value(a)	$	1,187,072,772
Cash		35,092,677
Receivable from securities sold		1,093,749
Receivable from fund shares sold		352,711
Dividends and interest receivable		1,449,326
Prepaid expenses		98,977
Total Assets		1,225,160,212
Liabilities:
Payable for fund shares redeemed		25,125,725
Payable for securities purchased		1,262,519
Payable to advisor (see note 3)		970,917
Accrued expenses		145,059
Total Liabilities		27,504,220
Net Assets	$	1,197,655,992
Shares Outstanding:
(shares of beneficial interest issued and outstanding, respectively, unlimited number of shares authorized with no par value)		70,677,490
Net asset value, offering price and redemption price	$	16.95
Analysis of net assets:
Capital	$	710,874,446
Accumulated earnings		486,781,546
Net Assets	$	1,197,655,992
(a) Investment securities at cost	$	700,973,373

See accompanying notes to the financial statements.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Statement of Operations Year Ended December 31, 2020

INVESTMENT INCOME:
Dividends(a)	$	7,632,276
Interest		49,278
Total Investment Income		7,681,554
EXPENSES:
Investment advisory fees (see note 3)		9,216,688
Transfer agent fees and expenses		91,607
Custodian fees and expenses		461,355
Accounting services fees		291,077
Other		352,732
Total expenses before reimbursed expenses		10,413,459
Earnings credit (see note 6)		(49,138)
Expense reimbursement (see note 3)		(226,159)
Total Expenses		10,138,162
NET INVESTMENT LOSS		(2,456,608)
NET REALIZED AND UREALIZED GAINS (LOSSES) FROM INVESTMENTS:
Net realized gains on investment transactions		148,239,381
Net realized losses on foreign currency transactions		(199,233)
Net realized gains on investment and foreign currency transactions		148,040,148
Change in net unrealized appreciation/depreciation on investments and translation of assets and liabilities denominated in foreign currencies		320,894,249
Net realized /unrealized gains on investments and foreign currencies		468,934,397
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	466,477,789

(a) Dividends are net of foreign withholding tax of $688,727

See accompanying notes to the financial statements.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Statements of Changes in Net Assets

	Year Ended December 31, 2020			Year Ended December 31, 2019
From Operations:
Net investment income (loss)		$	(2,456,608)		$	3,346,098
Net realized gains (losses) on investments and foreign currency transactions			148,040,148			(88,867,687)
Change in net unrealized appreciation/depreciation on investments and foreign currencies			320,894,249			264,263,933
Net increase in net assets resulting from operations			466,477,789			178,742,344
From Distributions:
Distributions to shareholders			(6,167,618)			(12,584,780)
Net decrease in net assets from distributions			(6,167,618)			(12,584,780)
From Capital Share Transactions:
Proceeds from sale of shares			134,419,225			153,882,218
Proceeds from reinvestment of distributions			5,771,139			11,061,099
Redemption of shares (see note 5)			(369,963,127)			(117,120,174)
Net increase (decrease) from capital share transactions			(229,772,763)			47,823,143
Total increase in net assets			230,537,408			213,980,707
Net Assets:
Beginning of year			967,118,584			753,137,877
End of year		$	1,197,655,992		$	967,118,584
Transactions in Shares:
Shares sold			11,605,267			15,512,876
Shares issued in reinvestment of distributions			339,879			1,061,357
Less shares redeemed			(34,201,645)			(11,788,870)
Net increase (decrease) from capital share transactions			(22,256,499)			4,785,363

See accompanying notes to the financial statements.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Notes to Financial Statements December 31, 2020

1.Description of Organization

2. Significant Accounting Policies

The following is a summary of significant accounting policies consistently followed by the Fund. These policies are in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The Fund is an investment company and follows accounting and reporting guidance under the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 946, “Financial Services — Investment Companies.”

Investment valuation. Investments in securities are stated at value as of the close of the regular trading session on the New York Stock Exchange (“NYSE”) (generally 3 p.m., Central Standard Time). Each listed and unlisted security for which last sale information is regularly reported is valued at the last reported sales price on that day. If there has been no sale on such day, then such security is valued at the current day’s bid price. Any unlisted security for which last sale information is not regularly reported and any listed debt security which has an inactive listed market for which over-the-counter market quotations are readily available are valued at the closing bid price determined on the basis of reasonable inquiry. Options are valued at the last reported bid price on the primary exchange as of the close of the regular trading session of the Chicago Board Options Exchange (“CBOE”). Restricted securities and any other securities or other assets for which market quotations are not readily available are valued by appraisal at their fair value as determined in good faith under procedures established by and under the general supervision and responsibility of the Board of Trustees. Short-term debt obligations, commercial paper and repurchase agreements are valued on the basis of quoted yields for securities of comparable maturity, quality and type or on the basis of amortized cost.

The Fund holds foreign equity securities. Foreign securities are fair valued as described in the following circumstances. Generally, trading in foreign securities markets is completed each day at various times prior to the close of the regular trading session of the NYSE. Due to the time differences between the closings of the relevant foreign securities exchanges and the close of the regular trading session of the NYSE for the Fund, the Fund will fair value their foreign investments when it is determined that the market quotations for the foreign investments either are not readily available or are unreliable and, therefore, do not represent fair value. When the fair value prices are utilized, these prices will attempt to reflect the impact of the U.S. financial markets’ perceptions and trading activities on the Funds’ foreign investments since the last closing prices of the foreign investments were calculated on their primary foreign securities markets or exchanges. For these purposes, the Board of Trustees of the Trust has determined that movements in relevant indices, after the close of the foreign securities exchanges, may demonstrate that market quotations are unreliable, and may trigger fair value pricing for certain securities. Consequently, fair valuation of portfolio securities may occur on a daily basis. In determining fair value prices, the Trust utilizes data furnished by an independent pricing service (and that data draws

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Notes to Financial Statements December 31, 2020 (continued)

upon, among other information, the market values of foreign investments). When a Fund uses fair value pricing, the values assigned to the Fund’s foreign investments may not be the quoted or published prices of the investments on their primary markets or exchanges.

Fair Value Measurements. In accordance with Financial Accounting Standards Board (“FASB”) guidance, the Fund utilizes the “Fair Value Measurements and Disclosures” to define fair value, set out a framework for measuring fair value, and expand disclosures regarding fair value measurements. The Fair Value Measurement Standard applies to fair value measurements already required or permitted by existing standards.

Various inputs are used in determining the value of the Fund’s investments. These inputs are summarized in the three levels listed below:

•

Level 1 — Quoted prices in active markets for identical securities.

•

Level 2 — Other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc).

•

Level 3 — Significant unobservable inputs (including the Fund’s own assumptions in determining the fair value of investments).

	Level 1			Level 2			Level 3
Investment Securities
Equities
Total Asia		$	24,776,529		$	491,006,862		$	—
Total Australia			—			43,429,310			—
Total Europe			53,035,709			503,477,332			—
Total North America			71,347,030			—			—
Total Investments		$	149,159,268		$	1,037,913,504		$	—

The Fund’s assets may include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation. The pricing service provides fair market valuation on days when the movement in relevant indices exceeds a predetermined threshold.

Foreign Currency Transactions. The accounting records of the Fund are maintained in U.S. dollars. Foreign currency amounts are translated into U.S. dollars at the current rate of exchange to determine the value of investments, assets and liabilities. Purchases and sales of securities, and income and expenses are translated at the prevailing rate of exchange on the respective date of these transactions. The Fund does not isolate that portion of the results of operations resulting from changes in foreign exchange rates on investments from fluctuations arising from changes in market prices of securities held. These fluctuations are included with the net realized and unrealized gains or losses from investments and foreign currencies.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Notes to Financial Statements December 31, 2020 (continued)

Fund share valuation. Fund shares are sold and redeemed on a continuous basis at net asset value. On each day the NYSE is open for trading, the net asset value per share is determined as of the later of the close of the NYSE or the CBOE by dividing the total value of investments and other assets, less liabilities, by the number of shares outstanding.

Investment transactions and investment income. Investment transactions are accounted for on the trade date (date the order to buy or sell is executed). Dividend income is recorded on the ex-dividend date, except that certain dividends from foreign securities are recorded as soon as the information is available to the Fund, and interest income is recorded on the accrual basis and includes amortization of premium and discount. Realized gains and losses from investment transactions are reported on an identified cost basis. Gains and losses on premiums from expired options are recognized on the date of expiration.

Federal income taxes and dividends to shareholders. It is the policy of the Fund to continue to comply with all requirements of the Internal Revenue Code of 1986, as amended (“the Code”), applicable to regulated investment companies and to distribute substantially all of their taxable income to their shareholders. The Fund has met the requirements of the Code applicable to regulated investment companies for the year ended December 31, 2020. Therefore, no federal income tax provision is required. Income and capital gains of the Fund are determined in accordance with both tax regulations and accounting principles generally accepted in the U.S. (“GAAP”). Such treatment may result in temporary and permanent differences between tax basis earnings and earnings reported for financial statement purposes. These reclassifications, which have no impact on the net asset value of the Fund, are primarily attributable to certain differences in computation of distributable income and capital gains under federal tax rules versus GAAP.

The Fund may utilize earnings and profits on redemption of shares as part of the dividends paid deduction.

For the year ended December 31, 2020, permanent book and tax differences resulting primarily from differing treatments for foreign currency transactions, and passive foreign investment company (“PFIC”) adjustments were identified and reclassified among the components of the Fund’s net assets.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Notes to Financial Statements December 31, 2020 (continued)

accounting have been reclassified to paid in capital, accumulated net investment loss and accumulated net realized gain as follows:

	Increases/(Decrease)
	Capital			Accumulated Earnings
International Opportunities Institutional Fund		$	(1,877,242)		$	1,877,242

The tax character of distributions paid during the fiscal year ended December 31, 2020 was as follows:

				Distributions Paid from Ordinary Income						Distributions Paid from Net Long-Term Capital Gains						Total Distributions Paid
	International Opportunities Institutional Fund				$	3,566,427					$	2,601,191					$	6,167,618

The tax character of distributions paid during the fiscal year ended December 31, 2019 was as follows:

				Distributions Paid from Ordinary Income						Distributions Paid from Net Long-Term Capital Gains						Total Distributions Paid
	International Opportunities Institutional Fund				$	12,584,780					$	—					$	12,584,780

The Fund utilized $123,633,297 of capital loss carryforward during the year ended December 31, 2020.

As of December 31, 2020 the components of accumulated earnings on a tax basis were as follows:

				Undistributed ordinary income						Undistributed long-term capital gains						Accumulated capital and other losses						Unrealized Appreciation on investments						Unrealized Depreciation foreign currency translations
	International Opportunities Institutional Fund				$	—					$	27,879,258					$	—					$	458,839,158					$	63,130

Accumulated capital and other losses consists of timing differences related to wash sales.

As of December 31, 2020 the cost of investments for federal income tax purposes are as follows:

			Cost of Investments for Federal Tax Purposes						Gross Unrealized Appreciation						Gross Unrealized (Depreciation)						Unrealized Appreciation
International Opportunities Institutional Fund				$	728,233,614					$	471,508,388					$	(12,669,230)					$	458,839,158

The Fund has reviewed all open tax years and major jurisdictions and concluded that there are no significant uncertain tax positions that would require recognition in the financial

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Notes to Financial Statements December 31, 2020 (continued)

statements. Open tax years are those that are open for exam by taxing authorities and as of December 31, 2020, open federal tax years included the tax years ended 2017 through 2020. The Fund has no examinations in progress and is also not aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months.

Indemnifications. Under the Trusts’ organizational documents, its present and former Officers and Trustees are indemnified against certain liabilities arising out of the performance of their duties to the Trust. In addition, in the normal course of business, the Trust enters into contracts that provide general indemnifications to other parties. The Trusts’ maximum exposure under these arrangements is unknown as this would involve future claims that may be made against the Trust that have not yet occurred. However, the Trust has not had prior claims or losses pursuant to these contracts and expects the risk of loss to be remote.

3. Transactions with affiliates

The Fund has written agreements with Oberweis Asset Management, Inc. (“OAM”) as the Fund’s investment adviser and manager. Oberweis Securities, Inc. (“OSI”), the Fund’s principal distributor, is an affiliate of OAM.

Investment advisory agreement. Under the Advisory Agreement, OAM provides investment advisory and management services to the Fund. The Fund paid monthly investment advisory and management fees at an annual rate equal to 1.00% of average daily net assets. For the year ended December 31, 2020, the International Opportunities Institutional Fund incurred investment advisory fees totaling $9,216,688.

Expense reimbursement. OAM is contractually obligated to reduce its investment advisory fees or reimburse the International Opportunities Institutional Fund to the extent that total ordinary operating expenses, as defined, exceed in any one year 1.10% expressed as a percentage of the Funds’ average daily net assets. For the year ended December 31, 2020 OAM reimbursed the Fund in the amount of $226,159.

Affiliated commissions. For the year ended December 31, 2020, the Fund did not execute any security transactions through OSI and therefore did not pay commissions to OSI.

4. Investment transactions

The cost of securities purchased and proceeds from securities sold during the year ended December 31, 2020, other than options written and money market investments, aggregated $1,218,752,250 and $1,463,865,980, respectively. The Fund did not hold government securities during the year ended December 31, 2020.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Notes to Financial Statements December 31, 2020 (continued)

The Fund may write covered call options. The premiums received provide a partial hedge (protection) against declining prices and enables the Fund to generate a higher return during periods when OAM does not expect the underlying security to make any major price moves in the near future but still deems the underlying security to be, over the long term, an attractive investment for the Fund. The Fund may write covered call options for which premiums received are recorded as liabilities and are subsequently adjusted to the current value of the options written. Premiums received from writing options that expire are treated as realized gains. Premiums received from writing options, which are either exercised or closed, are offset against the proceeds received or amount paid on the transaction to determine realized gains or losses. Amounts recovered for securities litigation are included in the realized gains of the Fund and are recorded when received. The Fund did not write covered call options during the year ended December 31, 2020.

5. Redemption fee

The Fund is designed for long-term investors. To discourage market timers, redemptions of shares within 90 days of purchase are subject to a 2% redemption fee of the total redemption amount. The redemption fee is deducted from the redemption proceeds and is retained by the Fund.

The redemption fee is retained by the Fund for the expense they incur in connection with shareholder redemptions. Redemption fees received by the Fund were $29,422 for the year ended December 31, 2020 and were recorded as a reduction of the redemption of shares in the Statements of Changes in Net Assets.

6. Earnings credits and interest charges

7. Subsequent events

In early 2020, an outbreak of a novel strain of coronavirus (COVID-19) emerged globally. This coronavirus has resulted in closing of international borders, enhanced health screenings, healthcare service preparation and delivery, quarantines, cancellations, disruptions to supply chains and customer activity, as well as general public concern and uncertainty. The impact of this outbreak has negatively affected the worldwide economy, as well as the economies of individual countries, the financial health of individual companies and the market in general in significant and unforeseen ways. The future impact of COVID-19 is currently unknown, and it may exacerbate other risks that apply to the Fund, including political, social and economic risks. Any such impact could adversely affect the Fund’s performance, the performance of the securities in which the Fund invests and may lead to losses on your investment in the Fund. The ultimate impact of COVID-19 on the financial performance of the Fund’s investments is not reasonably estimable at this time.

The Fund has evaluated subsequent events through the issuance of the financial statements and determined that no events have occurred that require disclosure.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Financial Highlights

Per share income and capital for a share outstanding throughout each year is as follows:

	Years Ended December 31,
	2020			2019			2018			2017			2016
Net asset value at beginning of year		$	10.41		$	8.54		$	12.77		$	9.72		$	10.32
Income (loss) from investment operations:
Net investment income (loss)a			(.03)			.04			.04			.03			.05
Net realized and unrealized gains (losses) on investments and foreign currency transactions			6.66			1.97			(3.11)			3.95			(.61)
Total from investment operations			6.63			2.01			(3.07)			3.98			(.56)
Redemption feesa			—c			—c			—c			—c			—c
Less dividends and distributions:
Dividends from net realized gains on investments and foreign currency transactions			(.04)			—			(1.15)			(.85)			—
Dividends from net investment income			(.05)			(.14)			(.01)			(.08)			(.04)
Total dividends and distributions			(.09)			(.14)			(1.16)			(.93)			(.04)
Net asset value at end of year		$	16.95		$	10.41		$	8.54		$	12.77		$	9.72
Total Return (%)			63.65			23.50			(23.91)			40.99			(5.43)
Ratio/Supplemental Data
Net Assets at end of year (in thousands)		$	1,197,656		$	967,119		$	753,138		$	1,041,117		$	657,477
Ratio of gross expenses to average net assets (%)			1.13			1.12			1.11			1.15			1.18
Ratio of net expenses to average net assets (%)b			1.10			1.08			1.08			1.10			1.10
Ratio of net investment income (loss) to average net assets (%)			(.27)			.37			.35			.29			.47
Portfolio turnover rate (%)			134			153			145			168			123d

Notes:

a The net investment income (loss) per share data and the redemption fee data were determined using average shares outstanding during the period.

b The ratios in this row reflect the impact, if any, of expense offset arrangements with the custodian and expense reimbursement from the advisor.

c Less than $0.005 per share

d Excludes the value of portfolio securities received as a result of in-kind purchases of the Fund’s capital shares

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Trustees of The Oberweis Funds and the Shareholders of Oberweis International Opportunities Institutional Fund

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities of Oberweis International Opportunities Institutional Fund, a series of shares of beneficial interest in The Oberweis Funds (the “Fund”), including the schedule of investments, as of December 31, 2020, and the related statement of operations for the year then ended, the statements of changes in net assets for each of the years in the two-year period then ended and the financial highlights for each of the years in the five-year period then ended, and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Fund as of December 31, 2020, and the results of its operations for the year then ended, the changes in its net assets for each of the years in the two-year period then ended and its financial highlights for each of the years in the five-year period then ended, in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Fund’s management. Our responsibility is to express an opinion on the Fund’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (“PCAOB”) and are required to be independent with respect to the Fund in accordance with the U.S. federal securities law and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Fund is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audit we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Fund’s internal control over financial reporting. Accordingly, we express no such opinion.

BBD, LLP

We have served as the auditor of one or more of the Funds in The Oberweis Funds since 2016.

Philadelphia, Pennsylvania
February 24, 2021

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TRUSTEES AND OFFICERS OF THE OBERWEIS FUNDS (unaudited)

Name, Address and Age	Position Held with Fund	Term of Office and Length of Time Served
NONINTERESTED TRUSTEES
Katherine Smith Dedrick (63) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Trustee	Trustee since November, 20041
Gary D. McDaniel (72) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Trustee	Trustee since April, 20041
James G. Schmidt (73) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Trustee	Trustee since December, 20031
INTERESTED TRUSTEES
James D. Oberweis (74) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Trustee2	Trustee since July, 19861
James W. Oberweis (46) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	President	Officer since August, 19963
Patrick B. Joyce (61) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Executive Vice President Chief Compliance Officer and Treasurer	Officer since October, 19943
David I. Covas (45) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Vice President	Officer since August, 20043
Kenneth S. Farsalas (50) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Vice President	Officer since August, 20093
Eric V. Hannemann (47) 3333 Warrenville Road, Suite 500 Lisle, IL 60532	Secretary	Officer since August, 20053

1 Unless otherwise noted, each trustee shall serve as a trustee of the Fund until the next meeting of shareholders, if any, called for the purpose of considering the election or re-election of such trustee or of a successor to such trustee, and until the election and qualification of his successor, if any, elected at such meeting, or until such trustee sooner dies, resigns, retires or is removed.

2 James D. Oberweis is an interested trustee of the Fund since he is a shareholder of Oberweis Asset Management, Inc., the Fund’s investment advisor.

3 Elected annually by board of trustees.

The Statement of Additional Information includes additional information about Fund officers and trustees and is available upon request without charge, by calling the Fund at 800-323-6166.

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TRUSTEES AND OFFICERS OF THE OBERWEIS FUNDS

(unaudited) (continued)

Principal Occupation Last Five Years	Number of Portfolios Overseen by Trustee	Other Directorships

President – Smith Dedrick Properties, Inc., 2016 to present; President – KSD Law P.C., 2015 to present; President – KSD Global Consulting, Inc., 2015 to present; Executive Committee Member, Risk Worldwide NZ Ltd., 2011 to 2016; President – Aggressive Publishing, Inc., 2010 to present; Member – Risk Worldwide LLC, 2007 to 2016; Partner – Childress Duffy, Ltd., 2007 to 2015.	7	None
	7	None
Senior Vice President and Chief Financial Officer – Federal Heath Sign Co., May 2003 to December 2019.	7	None

Illinois State Senator, January 2013 to January 2021; Chairman – Oberweis Dairy, Inc. December, 1986 to present.	7	None
President – Oberweis Asset Management, Inc., September, 2001 to present; Portfolio Manager from December, 1995 to present; President and Director – Oberweis Securities, Inc., September, 1996 to present.	Not Applicable	None
Executive Vice President, Secretary and Director – Oberweis Asset Management, Inc., September, 1994 to present; Executive Vice President and Director – Oberweis Securities, Inc. September, 1996 to present.	Not Applicable	None
Vice President – Oberweis Asset Management, Inc., September, 2003 to present.	Not Applicable	None
Vice President – Oberweis Asset Management, Inc., November 2004 to present.	Not Applicable	None
Vice President of Accounting – Oberweis Asset Management, Inc. and Oberweis Securities, Inc., June, 2004 to present.	Not Applicable	None

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Supplemental Information (unaudited)

Qualified Dividend Income

For the year ended December 31, 2020, 68.17% of the dividends paid from net investment income for the International Opportunities Institutional Fund is designated as qualified dividend income.

Foreign Taxes Paid

Pursuant to Section 853 of the Internal Revenue Code of 1986, as amended, the International Opportunities Institutional Fund designates $8,321,003 of income derived from foreign sources and $688,727 of foreign taxes paid for the period ended December 31, 2020.

			Foreign Source Income						Foreign Taxes Paid
International Opportunities Institutional Fund				$	0.1177					$	0.0097

Proxy Voting:

The Oberweis Fund has delegated authority to vote proxies related to the Oberweis International Opportunities Institutional Fund Portfolio securities to the Fund’s investment adviser, Oberweis Asset Management, Inc. (“OAM”). A description of the policies and procedures that OAM uses in fulfilling this responsibility is available, without charge upon request, by calling 1-800-323-6166. It also appears on www.oberweisfunds.com and in the Fund’s Statement of Additional Information, which can be found on the Securities and Exchange Commission’s (“SEC”) website at http://www.sec.gov. Information on how the Funds voted proxies relating to portfolio securities during the most recent 12 month period ended December 31 is available (1) without charge, upon request, by calling 1-800-323-6166, and (2) on the SEC’s website at http://www.sec.gov.

Availability of Schedules of Portfolio Investments:

The Fund files its complete schedule of portfolio investments with the SEC for the first and third quarter of each fiscal year (March 31 and September 30) on Form NPORT. The Fund’s Form NPORT are available, without charge, on the SEC’s website at http://www.sec.gov and may be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C. Information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330.

Approval of Investment Advisory Agreement:

The Investment Advisory and Management Agreement between The Oberweis Funds (the “Trust”) and Oberweis Asset Management, Inc. (“OAM”) (the “Advisory Agreement”) with respect to the International Opportunities Institutional Fund (the “Fund”) was last approved by the Board of Trustees of the Trust (the “Board”), including all of the trustees who are not

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Supplemental Information (unaudited) (continued)

parties to the Advisory Agreement or interested persons of any such party (the “independent trustees”), at a meeting on August 20, 2020. The Board, including a majority of the independent trustees, determined that the continuation of the Advisory Agreement was in the best interests of the Fund.

The Board noted that OAM has been associated with the Fund since its inception. The Board recognized that a long-term relationship with a capable, conscientious investment adviser is in the best interests of the Fund, and that shareholders have invested in the Fund knowing that OAM manages the Fund and knowing the investment advisory and management fee schedule.

Nature, Quality and Extent of Services. With respect to the nature, quality and extent of the services provided to the Fund by OAM pursuant to the Advisory Agreement, the Board considered the background and experience of OAM, the functions performed by OAM and the personnel providing such services, the management capabilities of OAM, the information contained in OAM’s Form ADV, OAM’s financial condition and the compliance reports provided to the Board, and the culture of compliance created by OAM, including the competency of the Trust’s chief compliance officer. The Board also considered the experience, academic background, long tenure, structure and size of the portfolio management/strategy investment team and its role, the investment process with respect to the types of investments held by the Fund, as well as the honesty and integrity of OAM, and that, in the Board’s experience, OAM personnel are open and forthright with the Board. In addition, the Board considered that OAM is a research-oriented firm that conducts extensive research in connection with managing the Fund and also considered the competitive pressure on active management.

The Board reviewed the investment performance of the Fund as compared to a peer universe of funds provided by Broadridge Financial Solutions, Inc. (“Broadridge”), an independent provider (the “Performance Universe”), and as compared to the performance of a relevant market benchmark index. With respect to Fund performance, the Board considered the Fund’s performance over the one-, three- and five-year periods ended June 30, 2020, as compared to the performance of the relevant market benchmark index and the Fund’s Performance Universe Average. The Board noted that the Fund outperformed its market benchmark index and Performance Universe Average for all periods reviewed. In light of the information provided and the considerations made, the Board concluded that the nature, quality and extent of the services provided to the Fund by OAM have been and are expected to remain satisfactory.

Fees and Expenses. The Board considered the combined investment advisory and management fees charged to the Fund by OAM (the “management fees”) as compared to the management fees of a peer group of funds provided by Broadridge (the “Expense Group”) and the expense ratio of the Fund as compared to the expense ratios of the Expense Group. The Board considered information provided by Broadridge on how it selected the peer funds included in the Expense Group for the Fund and considered certain limitations as to the comparability of the data provided. Based on the information provided, the Board noted that the management fees charged to the Fund were lower based on actual management fees than the median management fee of its Expense Group. The Board also noted that the expense ratio for the Fund was below the median of the expense ratio of the Expense Group.

In addition, the Board considered management fees paid to OAM by other clients. With respect to OAM’s other clients, the Board recognized that the mix of services provided to

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Supplemental Information (unaudited) (continued)

the Fund, the level of responsibility required under the Advisory Agreement with the Fund, and the regulatory, compliance and operational requirements with respect to the Fund are greater than OAM’s obligations for similar client accounts, and that the management fees for such accounts are less relevant to the Board’s consideration of the management fees for the Fund because they reflect different competitive forces than those in the mutual fund marketplace. Based on the information provided, the Board concluded that the Fund’s management fees were reasonable and appropriate in amount, given the nature, quality and extent of the services provided and taking into consideration relevant circumstances.

Profitability. With respect to the costs of services provided and profits realized by OAM, the Board considered the management fees received by OAM from the Fund as well as the level, quality and expense of OAM’s staff and the services that OAM provides. The Board also considered the explanation from OAM that the profits realized by OAM specifically from the relationship with the Fund could not be identified due to the impracticality of expense allocation, noting the difficulty of breaking down profitability related to the Fund versus the other Oberweis Funds and other client accounts because management and personnel time and services are not allocated between the various types of accounts. The Board noted OAM’s belief that, while the profits could not be itemized, the overall profitability of OAM was average and within a reasonable range relative to other investment advisory firms, and considered that OAM has contractually agreed to reimburse the Fund for expenses if its expense ratio exceeds a certain limit. Based on this information, the Board concluded for the Fund that OAM’s profitability was not unreasonable.

Economies of Scale. The Board considered the extent to which economies of scale would be realized as the Fund grows, and whether management fee levels reflect economies of scale for the benefit of Fund shareholders. The Board noted asset capacity constraints for the Fund which limit economies of scale. The Board concluded that the Fund’s management fees reflect an appropriate recognition of any economies of scale.

Other Benefits to OAM and Its Affiliates. The Board considered the character and amount of other incidental benefits received by OAM and its affiliates from their relationship with the Fund, including benefits to OAM and other OAM accounts related to soft dollars generated by the Fund’s brokerage transactions. The Board also noted that during the past year none of the Fund’s brokerage transactions had been placed through the affiliated broker-dealer of OAM.

After due consideration of all of the information and factors deemed relevant by the Board and based upon its own business judgment and the conclusions reached, the Board determined to approve the continuance of the Advisory Agreement. The Board, including the independent trustees, did not identify any single factor or group of factors as all-important or controlling, and considered all factors together.

Expense Examples:

As a shareholder of The Oberweis International Opportunities Institutional Fund, you may incur two types of costs: (1) transaction costs, including redemption fees and (2) ongoing costs, including management fees; distribution (and/or service) 12b-1 fees; and other Fund expenses. This example is intended to help you understand your ongoing costs (in dollars) of investing in The Oberweis International Opportunities Institutional Fund and to compare these costs with the ongoing costs of investing in other mutual funds.

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OBERWEIS INTERNATIONAL OPPORTUNITIES INSTITUTIONAL FUND

Supplemental Information (unaudited) (continued)

The Example is based on an investment of $1,000 investment at the beginning of the period and held for the entire period.

Actual Expenses:

The first line for each Fund in the table below provides information about actual account values and actual expenses. You may use the information below; together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000=8.6), then multiply the result by the number in the table under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Hypothetical Example for Comparison Purposes:

	Beginning Account Value 7/1/20			Ending Account Value 12/31/20			Expenses Paid During Period 7/1/20 – 12/31/20			Expense Ratio During Period 7/1/20 – 12/31/20
Actual		$	1,000.00		$	1,459.79		$	6.80		1.10%
Hypothetical		$	1,000.00		$	1,019.61		$	5.58		1.10%

* Expenses are equal to the average account value times the Fund’s annualized expense ratio multiplied by the number of days in the most recent fiscal half-year divided by the number of days in the fiscal year.

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Trustees and Officers

James D. Oberweis
Trustee

Gary D. McDaniel
Trustee

James W. Oberweis
President

David I. Covas
Vice President

Kenneth S. Farsalas
Vice President

Katherine Smith Dedrick
Trustee

James G. Schmidt
Trustee

Patrick B. Joyce
Executive Vice President
Chief Compliance Officer
Treasurer

Eric V. Hannemann
Secretary

Manager and Investment Advisor

Oberweis Asset Management, Inc.
3333 Warrenville Road, Suite 500, Lisle, IL 60532
800-323-6166
oberweisfunds.com

Distributor

Oberweis Securities, Inc.
3333 Warrenville Road, Suite 500, Lisle, IL 60532
630-577-2300
oberweisfunds.com

Custodian

UMB Bank, n.a.
928 Grand Blvd., Kansas City, MO 64106

Transfer Agent

UMB Fund Services, Inc.
P.O. Box 711, Milwaukee, WI 53201-0711
800-245-7311

Counsel

Vedder Price P.C.
222 North LaSalle Street, Chicago, IL 60601

Independent Registered Public Accounting Firm

BBD, LLP
1835 Market Street, 3rd Floor, Philadelphia, PA 19103

International Opportunities Institutional Fund

800-245-7311

oberweisfunds.com

Audit Fees include amounts related to the audit of the registrant’s annual financial statements and services normally provided by the principal accountant in connection with statutory and regulatory filings. Tax Fees principally include tax compliance, tax advice, tax planning and preparation of tax returns.

(e)(1) The registrant’s audit committee pre-approves all audit services provided by the registrant’s principal accountant for the registrant and all non-audit services provided by the registrant’s principal accountant for the registrant, its investment adviser and any entity controlling, controlled by, or under common control with the investment adviser (“Adviser Affiliate”) that provides ongoing services to the registrant, if the engagement by the investment adviser or Adviser Affiliate relates directly to the operations and financial reporting of the registrant.

(e)(2) No services included in (b) – (d) above were approved pursuant to paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X.

(g) The aggregate fees billed for the most recent fiscal year and the preceding fiscal year by the registrant’s principal accountant for non-audit services rendered to the registrant, its investment, and Adviser Affiliate that provides ongoing services to the registrant for 2020 and 2019 were $29,000. and $29,000, respectively.

(h) Non-audit services rendered to the registrant’s investment adviser and any Adviser Affiliate that were not pre-approved pursuant to Paragraph (c) (7) (ii) of Rule 2-01 of Regulation S-X were considered by the registrant’s audit committee as to whether they were compatible with maintaining the principal account’s independence.

There have been no material changes to the procedures by which shareholders may recommend nominees to the registrant’s board of trustees since registrant last disclosed such procedures in its proxy statement dated April 16, 2004.

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

	INVESTOR CLASS	INSTITUTIONAL CLASS
Oberweis Micro-Cap Fund	OBMCX	OMCIX
Oberweis Small-Cap Opportunities Fund	OBSOX	OBSIX
Oberweis Global Opportunities Fund	OBEGX	OBGIX
Oberweis China Opportunities Fund	OBCHX	OCHIX
Oberweis International Opportunities Fund	OBIOX	—
Oberweis Emerging Markets Fund	OBEMX	OIEMX

	President’s Letter					1
	Management Discussion on Fund Performance					4
	Schedule of Investments
	Oberweis Micro-Cap Fund					15
	Oberweis Small-Cap Opportunities Fund					19
	Oberweis Global Opportunities Fund					23
	Oberweis China Opportunities Fund					26
	Oberweis International Opportunities Fund					30
	Oberweis Emerging Markets Fund					33
	Statements of Assets and Liabilities
	Oberweis Micro-Cap Fund					37
	Oberweis Small-Cap Opportunities Fund					37
	Oberweis Global Opportunities Fund					37
	Oberweis China Opportunities Fund					38
	Oberweis International Opportunities Fund					38
	Oberweis Emerging Markets Fund					38
	Statements of Operations
	Oberweis Micro-Cap Fund					39
	Oberweis Small-Cap Opportunities Fund					39
	Oberweis Global Opportunities Fund					40
	Oberweis China Opportunities Fund					40
	Oberweis International Opportunities Fund					40
	Oberweis Emerging Markets Fund					40
	Statements of Changes in Net Assets
	Oberweis Micro-Cap Fund					41
	Oberweis Small-Cap Opportunities Fund					42
	Oberweis Global Opportunities Fund					43
	Oberweis China Opportunities Fund					44
	Oberweis International Opportunities Fund					45
	Oberweis Emerging Markets Fund					46
	Notes to the Financial Statements					47
	Financial Highlights
	Oberweis Micro-Cap Fund					56
	Oberweis Small-Cap Opportunities Fund					58
	Oberweis Global Opportunities Fund					60
	Oberweis China Opportunities Fund					62
	Oberweis International Opportunities Fund					64
	Oberweis Emerging Markets Fund					65
	Report of Independent Registered Public Accounting Firm					67
	Trustees and Officers of the Oberweis Funds					70
	Supplemental Information					72

	Shares		Value
Textiles Apparel & Shoes – 3.4%
Crocs, Inc.*		4,300		$	269,438
Deckers Outdoor Corp.*		1,000			286,780
					556,218
Utilities — Telecommunications – 1.0%
Vonage Hldgs. Corp.*		12,000			154,500
Total Equities
(Cost: $11,605,119)				$	16,716,975
Total Investments – 100.5%
(Cost: $11,605,119)				$	16,716,975
Other Liabilities Less Assets – (0.5)%					(84,169)
Net Assets – 100%				$	16,632,806

Sector Allocations (As a Percentage of Net Assets) (unaudited)
Communication Services					7.9%
Consumer Discretionary					22.0%
Consumer Staples					8.6%
Energy					5.8%
Financials					4.2%
Healthcare					5.3%
Industrials					11.8%
Information Technology					27.2%
Materials					4.8%
Real Estate					1.3%

	Communication Services					9.2%
	Consumer Discretionary					23.2%
	Consumer Staples					1.8%
	Energy					1.0%
	Financials					7.7%
	Healthcare					9.6%
	Industrials					19.6%
	Information Technology					21.2%
	Materials					4.8%
	Real Estate					1.0%

	(a)	As of December 31, 2020, the registrant has adopted a code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer, or persons performing similar functions.

	(b)	During the period covered by this report, there were not any amendments to a provision of the Code of Ethics adopted in 2(a) above.

	(c)	During the period covered by this report, there were no waivers, including any implicit waivers, from a provision of the Code of Ethics described in 2(a) above that relates to one or more of the items set forth in paragraph (b) of this item’s instructions.


	2019	2020
Audit fees	125,500	125,500
Audit-Related Fees	N/A	N/A
Tax Fees	29,000	29,000
All Other Fees	N/A	N/A


(a) (1)		Code of Ethics applicable to its Principal Executive and Principal Accounting Officers pursuant to Section 406 of the Sarbanes-Oxley Act of 2002 attached hereto as Exhibit 99.406. Code of Ethics.

(a) (2)		Certifications pursuant to Rule 30a-2 under the Investment Company Act of 1940 (17CFR 270.30a-2) in the exact form set forth below: EX-99.CERT attached hereto.

(a) (3)		Any written solicitation to purchase securities under Rule 23 c-1 under the Investment Company Act of 1940 (17 CFR 270.23c-1) sent or given during the period covered by the report by or on behalf of the registrant to 10 or more persons. Not Applicable to the registrant.



(b)		If the report is filed under Section 13(a) or 15(d) of the Exchange Act, provide the certifications required by Rule 30a-2(b) under the 1940 Act (17 CFR 270.30a-2(b)), Rule 13a-14(b) or Rule 15d-14(b) under the Exchange Act (17 CFR 240.13a-14(b) or 240.15d-14(b)), and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. 1350) as an exhibit. A certification furnished pursuant to this paragraph will not be deemed “filed” for purposes of Section 18 of the Exchange Act (15 U.S. C. 78r), or otherwise subject to the liability of that section. Such certification will not be deemed to be incorporated by reference into any filing under the Securities Act of 1933 or the Exchange Act, except to the extent that the registrant specifically incorporates it by reference. EX-99.906 CERT attached hereto.


(Registrant) The Oberweis Funds

By (Signature and Title*)		/s/ James W. Oberweis
		James W. Oberweis
		President, The Oberweis Funds


By (Signature and Title*)		/s/ Patrick B. Joyce
		Patrick B. Joyce
		Executive Vice President and Treasurer,
		The Oberweis Funds