Filed Pursuant to Rule 424(b)(5)
Registration No. 333-189015

PROSPECTUS SUPPLEMENT
(to Prospectus dated June 17, 2013)

5,700,000 Shares
  
Common Stock

We are offering 5,700,000 shares of our common stock, $0.001 par value per share, in this offering.

Our common stock is listed on The NASDAQ Capital Market under the symbol “TGTX.” On July 17, 2013, the last reported sale price of our common stock on The NASDAQ Capital Market was $6.87 per share.

Investing in our common stock involves a high degree of risk. See “Risk Factors” beginning on page S-5.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

	Per share		Total
Public offering price	$	6.15	$	35,055,000
Underwriting discount (1)	$	0.369	$	2,103,300
Proceeds, before expenses, to us	$	5.781	$	32,951,700

(1) In addition, we have agreed to reimburse the underwriters for certain out-of-pocket expenses. See “Underwriting” in this prospectus supplement for additional information.

We have granted the underwriters an option for a period of 30 days from the date of this prospectus supplement to purchase up to 855,000 additional common shares to cover any overallotments.

The underwriters expect to deliver the common stock on or about July 23, 2013 only in book-entry form through the facilities of The Depository Trust Company.

Roth Capital Partners	Ladenburg Thalmann & Co. Inc.	Brean Capital

National Securities Corporation

Prospectus Supplement, dated July 18, 2013

Table of Contents

Prospectus Supplement

	Page
About This Prospectus Supplement		S-1
Special Cautionary Notice Regarding Forward-Looking Statements		S-2
Summary		S-3
Risk Factors		S-5
Use of Proceeds		S-7
Price Range of our Common Stock		S-7
Capitalization		S-8
Dilution		S-9
Underwriting		S-10
Notice to Investors		S-13
Legal Matters		S-15
Experts		S-15
Where You Can Find More Information		S-15
Incorporation of Certain Information by Reference		S-15

Prospectus

	Page
TG Therapeutics, Inc.		1
The Offering		1
Where You Can Find More Information		1
Important Information About This Prospectus		2
Incorporation of Certain Information by Reference		2
Description of Common Stock		3
Plan of Distribution		4
Legal Matters		5
Experts		5

S-ii

About This Prospectus Supplement

This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this common stock offering and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference herein. The second part, the accompanying prospectus, provides more general information. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. To the extent there is a conflict between the information contained in this prospectus supplement and the information contained in the accompanying prospectus or any document incorporated by reference therein filed prior to the date of this prospectus supplement, you should rely on the information in this prospectus supplement; provided that if any statement in one of these documents is inconsistent with a statement in another document having a later date — for example, a document incorporated by reference in the accompanying prospectus — the statement in the document having the later date modifies or supersedes the earlier statement.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

Neither we nor the underwriters have authorized anyone to provide information different from that contained in this prospectus supplement and the accompanying prospectus, including any free writing prospectus that we have authorized for use in this offering. When you make a decision about whether to invest in our common stock, you should not rely upon any information other than the information in this prospectus supplement or the accompanying prospectus, including any free writing prospectus that we have authorized for use in this offering. Neither the delivery of this prospectus supplement or the accompanying prospectus, including any free writing prospectus that we have authorized for use in this offering, nor the sale of our common stock means that information contained in this prospectus supplement and the accompanying prospectus, including any free writing prospectus that we have authorized for use in this offering, is correct after their respective dates. It is important for you to read and consider all information contained in this prospectus supplement and the accompanying prospectus, including the information incorporated by reference into this prospectus supplement and the accompanying prospectus, and any free writing prospectus that we have authorized for use in connection with this offering in making your investment decision. You should also read and consider the information in the documents to which we have referred you in the sections entitled “Where You Can Find More Information” and “Incorporation of Certain Information by Reference” in this prospectus supplement.

We are offering to sell, and seeking offers to buy, shares of our common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the accompanying prospectus must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement and the accompanying prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

Unless otherwise stated, all references in this prospectus to “we,” “us,” “our,” “TG,” the “Company” and similar designations refer to TG Therapeutics, Inc. and our subsidiaries. This prospectus supplement contains trademarks and trade names of TG Therapeutics, Inc., including our name and logo. Other service marks, trademarks and trade names referred to in this document are the property of their respective owners.

S-1

Special Cautionary Notice Regarding Forward-Looking Statements

Certain matters discussed in this prospectus supplement and the accompanying prospectus may constitute forward-looking statements for purposes of the Securities Act of 1933, as amended, or the Securities Act, and the Securities Exchange Act of 1934, as amended, or the Exchange Act, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from the future results, performance or achievements expressed or implied by such forward-looking statements. The words “anticipate,”“believe,”“estimate,”“may,”“expect” and similar expressions are generally intended to identify forward-looking statements. Our actual results may differ materially from the results anticipated in these forward-looking statements due to a variety of factors, including, without limitation, those discussed under the captions “Risk Factors,”“Management’s Discussion and Analysis of Financial Condition and Results of Operations” and elsewhere in this prospectus supplement and the accompanying prospectus, as well as other factors which may be identified from time to time in our other filings with the Securities and Exchange Commission, or the SEC, or in the documents where such forward-looking statements appear. All written or oral forward-looking statements attributable to us are expressly qualified in their entirety by these cautionary statements. Such forward-looking statements include, but are not limited to, statements about our:

• expectations for increases or decreases in expenses;

• expectations for the pre-clinical and clinical development, manufacturing, regulatory approval, and commercialization (including market acceptance) of TG-1101, TGR-1202 or any other products we may acquire or in-license;

• expectations for incurring capital expenditures to expand our research and development and manufacturing capabilities;

• expectations for generating revenue or becoming profitable on a sustained basis;

• expectations or ability to enter into marketing and other partnership agreements;

• expectations or ability to enter into product acquisition and in-licensing transactions;

• expectations or ability to build our own commercial infrastructure to manufacture, market and sell our drug candidate;

• estimates of the sufficiency of our existing cash and cash equivalents and investments to finance our operating requirements, including expectations regarding the value and liquidity of our investments;

• expected losses; and

• expectations for future capital requirements.

The forward-looking statements contained in this prospectus supplement and the accompanying prospectus reflect our views and assumptions only as of the date of this prospectus supplement and the accompanying prospectus, respectively. Except as required by law, we assume no responsibility for updating any forward-looking statements.

We qualify all of our forward-looking statements by these cautionary statements. In addition, with respect to all of our forward-looking statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995.

S-2

Summary

This summary highlights information contained elsewhere or incorporated by reference in this prospectus supplement and the accompanying prospectus and in the documents we incorporate by reference. This summary does not contain all of the information that you should consider before deciding to invest in our common stock. You should read this entire prospectus supplement and the accompanying prospectus carefully, including the “Risk Factors” section contained in this prospectus supplement and our consolidated financial statements and the related notes and the other documents incorporated by reference herein.

Our Business

We are a biopharmaceutical company focused on the acquisition, development and commercialization of innovative and medically important pharmaceutical products for the treatment of cancer and other underserved therapeutic needs. We aim to acquire rights to these technologies by licensing or otherwise acquiring an ownership interest, funding their research and development and eventually either out-licensing or bringing the technologies to market.

Currently, we are developing two therapies targeting hematological malignancies. TG-1101 (ublituximab) is a novel, third generation monoclonal antibody that targets a specific and unique epitope on the CD20 antigen found on mature B-lymphocytes. We are also developing TGR-1202, an orally available PI3K delta inhibitor.

We also actively evaluate complementary products, technologies and companies for in-licensing, partnership, acquisition and/or investment opportunities. To date, we have not received approval for the sale of any of our drug candidates in any market and, therefore, have not generated any product sales from our drug candidates.

Company Information

Our principal executive offices are located at 787 Seventh Avenue, New York, New York 10019, and our telephone number is 212-554-4484. We maintain a website on the Internet at www.tgtherapeutics.com and our e-mail address is info@tgtxinc.com. Our Internet website, and the information contained on it, are not to be considered part of this prospectus supplement or the accompanying prospectus. For further information regarding us and our financial information, you should refer to our recent filings with the SEC. See “Where You Can Find More Information” and “Incorporation of Certain Information by Reference.”

S-3

The Offering

Common stock offered by us

5,700,000 shares

Common stock to be outstanding after the offering

32,022,671 shares

Overallotment option

855,000 shares

Use of Proceeds

We intend to use the net proceeds of this offering for the continued development of TG-1101 and TGR-1202, the acquisition, development and commercialization of other pharmaceutical products, and for general corporate purposes. See the section entitled “Use of Proceeds” on page S-7 of this prospectus supplement.

Risk Factors

See “Risk Factors” beginning on page S-5 for a discussion of factors that you should consider before buying shares of our common stock.

The NASDAQ Capital Market Symbol

TGTX

The number of shares of common stock to be outstanding after the offering is based on 26,322,671 shares of common stock outstanding as of March 31, 2013 and excludes, as of that date:

• 6,364,598 shares of common stock issuable upon the exercise of outstanding warrants with a weighted average exercise price of $1.53 per share;

• 46,591 shares of common stock issuable upon the exercise of outstanding stock options with a weighted average exercise price of $46.37 per share;

• 17,403 shares of common stock issuable upon the conversion of outstanding notes payable with a weighted average conversion price of $1,078.04 per share; and

• an aggregate of 1,966,733 shares of common stock reserved for future issuance under our stock option and incentive plans.

Except as otherwise indicated, all information in this prospectus supplement assumes no exercise by the underwriters of their overallotment option.

S-4

Risk Factors

Investment in our common stock involves risks. Before deciding whether to invest in our common stock, you should consider carefully the risk factors discussed below and those contained in the section entitled “Risk Factors” contained in our Annual Report on Form 10-K for the year ended December 31, 2012, as filed with the SEC on March 21, 2013, which is incorporated herein by reference in its entirety, as well as any amendment or update to our risk factors reflected in subsequent filings with the SEC. If any of the risks or uncertainties described in our SEC filings actually occurs, our business, financial condition, results of operations or cash flow could be materially and adversely affected. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment. The risks and uncertainties we have described are not the only ones facing our company. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business operations.

Risks Related to this Offering

Future sales or other issuances of our common stock could depress the market for our common stock.

Sales of a substantial number of shares of our common stock, or the perception by the market that those sales could occur, could cause the market price of our common stock to decline or could make it more difficult for us to raise funds through the sale of equity in the future.

In connection with this offering, we and our directors and officers have entered into lock-up agreements for a period of 90 days following this offering (which period may be extended under certain circumstances). We and our directors and officers may be released from lock-up prior to the expiration of the lock-up period at the discretion of the representative of the several underwriters. See “Underwriting.” Upon expiration or earlier release of the lock-up, we and our directors and officers may sell shares into the market, which could adversely affect the market price of shares of our common stock.

Future issuances of common stock could further depress the market for our common stock.

If we make one or more significant acquisitions in which the consideration includes stock or other securities, our stockholders’ holdings may be significantly diluted. In addition, stockholders’ holdings may also be diluted if we enter into arrangements with third parties permitting us to issue shares of common stock in lieu of certain cash payments upon the achievement of milestones.

Our stock price can be volatile, which increases the risk of litigation, and may result in a significant decline in the value of your investment.

The trading price of our common stock is likely to be highly volatile and subject to wide fluctuations in price in response to various factors, many of which are beyond our control. These factors include:

• developments concerning our drug candidates, including the safety and efficacy results from clinical trials and regulatory filings and approvals;

• announcements of technological innovations by us or our competitors;

• introductions or announcements of new products by us or our competitors;

• announcements of significant acquisitions, strategic partnerships, joint ventures or capital commitments involving us or our competitors;

• changes in financial estimates by securities analysts;

• actual or anticipated variations in quarterly or annual operating results;

• expectations regarding our financial condition;

• expiration or termination of licenses, research contracts or other collaboration agreements;

• conditions or trends in the regulatory climate and the biotechnology and pharmaceutical industries;

• changes in the market valuations of similar companies;

S-5

• negative comments and sentiment in the media; and

• additions or departures of key personnel.

In addition, equity markets in general, and the market for biotechnology and life sciences companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of companies traded in those markets. These broad market and industry factors may materially affect the market price of our common stock, regardless of our development and operating performance. In the past, following periods of volatility in the market price of a company’s securities, securities class-action litigation has often been instituted against that company. Such litigation, if instituted against us, could cause us to incur substantial costs to defend such claims and divert management’s attention and resources, which could seriously harm our business.

Certain anti-takeover provisions in our charter documents and Delaware law could make a third-party acquisition of us difficult. This could limit the price investors might be willing to pay in the future for our common stock.

Provisions in our amended and restated certificate of incorporation and restated bylaws could have the effect of making it more difficult for a third party to acquire, or of discouraging a third party from attempting to acquire, or control us. These factors could limit the price that certain investors might be willing to pay in the future for shares of our common stock. Our amended and restated certificate of incorporation allows us to issue preferred stock without the approval of our stockholders. The issuance of preferred stock could decrease the amount of earnings and assets available for distribution to the holders of our common stock or could adversely affect the rights and powers, including voting rights, of such holders. In certain circumstances, such issuance could have the effect of decreasing the market price of our common stock. Our restated bylaws eliminate the right of stockholders to call a special meeting of stockholders, which could make it more difficult for stockholders to effect certain corporate actions. Any of these provisions could also have the effect of delaying or preventing a change in control.

We have broad discretion to use the net proceeds from this offering and our investment of these proceeds pending any such use may not yield a favorable return.

Our management has broad discretion as to how to spend the proceeds from this offering and may spend these proceeds in ways with which our stockholders may not agree. Pending any such uses, we plan to invest the net proceeds of this offering in short-term and long-term, investment-grade, interest-bearing securities. These investments may not yield a favorable return to our stockholders.

You will experience immediate and substantial dilution.

Since the public offering price of the shares of common stock offered pursuant to this prospectus supplement and the accompanying prospectus is higher than the net tangible book value per share of our common stock, you will suffer substantial dilution in the net tangible book value of the common stock you purchase in this offering. See “Dilution” in this prospectus supplement for a more detailed discussion of the dilution you will incur if you purchase shares of our common stock in this offering.

S-6

Use of Proceeds

We estimate that the net proceeds of this offering, after deducting the underwriting discount and estimated offering expenses payable by us will be approximately $32.5 million (or approximately $37.5 million if the underwriters’ overallotment option is exercised in full).

We intend to use the net proceeds from this offering:

• to fund the ongoing development of TG-1101 and TGR-1202;

• to potentially in-license, acquire and develop additional drug candidates; and

• for general corporate purposes.

The timing and amounts of our actual expenditures will depend on several factors, including the progress of our research and development programs, the results of other pre-clinical and clinical studies and the timing and costs of regulatory approvals. As of the date of this prospectus supplement, we cannot specify with certainty the particular uses of the proceeds from this offering. As a result, our management will retain broad discretion in the allocation and use of the net proceeds from this offering. Pending the uses described above, we will invest the net proceeds in short-term and long-term, investment grade, interest-bearing securities.

Price Range of our Common Stock

Our common stock was listed on the NASDAQ Capital Market on May 30, 2013 and trades under the symbol “TGTX.” Prior to May 30, 2013, the Company’s stock traded in the Over-the-Counter Bulletin Board. On July 17, 2013, the last reported sale price of our common stock was $6.87 per share.

The following table sets forth the high and low closing sale prices of our common stock for the periods indicated.

	High		Low
2011
First Quarter	$	0.08	$	0.01
Second Quarter		0.02		0.01
Third Quarter		1.50		0.01
Fourth Quarter		0.20		0.02
2012
First Quarter	$	.90	$	0.02
Second Quarter		6.75		0.10
Third Quarter		6.25		2.23
Fourth Quarter		4.10		1.82
2013
First Quarter	$	6.73	$	3.52
Second Quarter		7.75		4.95
Third Quarter (through July 17, 2013)		6.87		6.13

Dividend policy

We have never declared or paid any cash dividends on our common stock and do not anticipate paying any cash dividends in the foreseeable future. Any future determination to pay dividends will be at the discretion of our board of directors.

S-7

Capitalization

The following table sets forth our capitalization as of March 31, 2013:

• on an actual basis; and

• on an as adjusted basis to reflect the sale of the 5,700,000 shares of common stock offered by us after deducting the underwriting discount and estimated offering expenses payable by us.

You should read this information together with our financial statements and the notes to those statements incorporated by reference into this prospectus supplement and the related prospectus.

March 31, 2013 (unaudited) (in thousands, except share data)	Actual			As Adjusted
Cash and cash equivalents		15,188,167			47,739,867
Stockholders’ equity:
Preferred stock, $0.001 par value per share, 10,000,000 shares authorized; none issued and outstanding, actual and as adjusted		—			—
Common stock, $0.001 par value per share, 500,000,000 shares authorized; 26,322,671 shares actual and 32,022,671 shares as adjusted, issued and outstanding		26,323			32,023
Additional paid-in capital		37,356,700			69,902,700
Treasury stock, at cost, 13,526 shares, actual and as adjusted		(84,538	)		(84,538	)
Accumulated deficit		(22,599,404	)		(22,599,404	)
Total stockholders’ equity		14,699,087			47,250,781
Total capitalization		14,699,087			47,250,781

The table excludes the following as of March 31, 2013:

• 6,364,598 shares of common stock issuable upon the exercise of outstanding warrants with a weighted average exercise price of $1.53 per share;

• 46,591 shares of common stock issuable upon the exercise of stock options outstanding with a weighted average exercise price of $46.37 per share;

• 17,403 shares of common stock issuable upon the conversion of notes payable with a weighted average conversion price of $1,078.04 per share; and

• an aggregate of 1,966,733 shares of common stock reserved for future issuance under our stock option and incentive plans.

S-8

Dilution

Purchasers of the shares offered by this prospectus supplement and the accompanying prospectus will suffer immediate and substantial dilution in the net tangible book value per share of the common stock they purchase. Net tangible book value per share represents the amount of total tangible assets less total liabilities, divided by the number of shares of our common stock outstanding as of March 31, 2013. Our net tangible book value as of March 31, 2013 was approximately $13.9 million, or $0.53 per share of our common stock.

Dilution in net tangible book value per share represents the difference between the amount per share paid by purchasers in this offering and the net tangible book value per share of our common stock immediately after this offering. After giving effect to sale of 5,700,000 shares of common stock in this offering at a public offering price of $6.15 per share, and after deducting the underwriting discount and the estimated offering expenses payable by us, our as adjusted net tangible book value as of March 31, 2013 would have been approximately $1.45 per share of common stock. This represents an immediate increase in net tangible book value of $0.92 per share of common stock to our existing stockholders and an immediate dilution in net tangible book value of $4.70 per share of common stock to purchasers in this offering. The following table illustrates this per share dilution:

Public offering price per share			$	6.15
Net tangible book value per share as of March 31, 2013	$	0.53
Increase per share attributable to this offering	$	0.92
As adjusted net tangible book value per share as of March 31, 2013 after this offering			$	1.45
Dilution per share to new investors participating in this offering			$	4.70

The above table is based on 26,322,671 shares of common stock outstanding as of March 31, 2013 and excludes, as of that date:

• 6,364,598 shares of common stock issuable upon the exercise of outstanding warrants with a weighted average exercise price of $1.53 per share;

• 46,591 shares of common stock issuable upon the exercise of outstanding stock options with a weighted average exercise price of $46.37 per share;

• 17,403 shares of common stock issuable upon the conversion of outstanding notes payable with a weighted average conversion price of $1,078.04 per share; and

• an aggregate of 1,966,733 shares of common stock reserved for future issuance under our stock option and incentive plans.

If the underwriters exercise in full their option to purchase 855,000 additional shares of our common stock at the public offering price, the as adjusted net tangible book value after this offering would be $1.56 per share, representing an increase in net tangible book value of $1.03 per share to existing stockholders and immediate dilution in net tangible book value of $4.59 per share to purchasers in this offering.

To the extent that any options or warrants are exercised, new options are issued under our equity incentive plans or we otherwise issue additional shares of common stock in the future at a price less than the public offering price, there will be further dilution to new investors.

S-9

Underwriting

We have entered into an underwriting agreement with Roth Capital Partners, LLC, acting as the representative of the several underwriters named below, with respect to the shares of common stock subject to this offering. Subject to certain conditions, we have agreed to sell to the underwriters, and the underwriters have severally agreed to purchase, the number of shares of common stock provided below opposite their respective names.

Underwriters	Number of Shares
Roth Capital Partners, LLC		1,510,500
Ladenburg Thalmann & Co. Inc.		1,510,500
Brean Capital, LLC		1,510,500
National Securities Corporation		1,168,500
Total		5,700,000

The underwriters are offering the shares of common stock subject to their acceptance of the shares of common stock from us and subject to prior sale. The underwriting agreement provides that the obligations of the several underwriters to pay for and accept delivery of the shares of common stock offered by this prospectus supplement and the accompanying prospectus are subject to the approval of certain legal matters by their counsel and to certain other conditions. The underwriters are obligated to take and pay for all of the shares of common stock if any such shares are taken. However, the underwriters are not required to take or pay for the shares of common stock covered by the underwriters’ over-allotment option described below.

Over-Allotment Option

We have granted the underwriters an option, exercisable for 30 days from the date of this prospectus supplement, to purchase up to an aggregate of 855,000 additional shares of common stock to cover over-allotments, if any, at the public offering price set forth on the cover page of this prospectus supplement, less the underwriting discount. The underwriters may exercise this option solely for the purpose of covering over-allotments, if any, made in connection with the offering of the shares of common stock offered by this prospectus supplement and the accompanying prospectus. If the underwriters exercise this option, each underwriter will be obligated, subject to certain conditions, to purchase a number of additional shares proportionate to that underwriter’s initial purchase commitment as indicated in the table above.

Discount, Commissions and Expenses

The underwriters have advised us that they propose to offer the shares of common stock to the public at the initial public offering price set forth on the cover page of this prospectus supplement and to certain dealers at that price less a concession not in excess of $0.1845 per share. After this offering, the initial public offering price and concession to dealers may be changed by the representative. No such change shall change the amount of proceeds to be received by us as set forth on the cover page of this prospectus supplement. The shares of common stock are offered by the underwriters as stated herein, subject to receipt and acceptance by them and subject to their right to reject any order in whole or in part. The underwriters have informed us that they do not intend to confirm sales to any accounts over which they exercise discretionary authority.

The following table shows the underwriting discount payable to the underwriters by us in connection with this offering. Such amounts are shown assuming both no exercise and full exercise of the underwriters’ over-allotment option to purchase additional shares.

	Per share		Total Without Exercise of Over-Allotment Option		Total With Exercise of Over-Allotment Option
Public offering price	$	6.150	$	35,055,000	$	40,313,250
Underwriting discount	$	0.369	$	2,103,300	$	2,418,795

S-10

We estimate that expenses payable by us in connection with this offering, other than the underwriting discount referred to above, will be approximately $312,000. We have agreed to reimburse the underwriters for certain out-of-pocket expenses not to exceed $75,000. In no event will the total compensation payable to the underwriters and any other member of the Financial Industry Regulatory Authority, Inc. or independent broker-dealer (including any financial advisor) in connection with the sale of the common stock offered hereby exceed 8.0% of the gross proceeds of this offering.

Indemnification

We have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as amended, or the Securities Act, and liabilities arising from breaches of representations and warranties contained in the underwriting agreement, or to contribute to payments that the underwriters may be required to make in respect of those liabilities.

Lock-up Agreements

We, our officers, directors and certain of our stockholders have agreed, subject to limited exceptions, for a period of 90 days after the date of the underwriting agreement, not to offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise dispose of, directly or indirectly any shares of common stock or any securities convertible into or exchangeable for our common stock either owned as of the date of the underwriting agreement or thereafter acquired without the prior written consent of the representative. This 90-day period may be extended if (1) during the last 17 days of the 90-day period, we issue an earnings release or material news or a material event regarding us occurs or (2) prior to the expiration of the 90-day period, we announce that we will release earnings results during the 16-day period beginning on the last day of the 90-day period, then the period of such extension will be 18 days, beginning on the issuance of the earnings release or the occurrence of the material news or material event. If after any announcement described in clause (2) of the preceding sentence, we announce that we will not release earnings results during the 16-day period, the lock-up period shall expire the later of the expiration of the 90-day period and the end of any extension of such period made pursuant to clause (1) of the preceding sentence. The representative may, in its sole discretion and at any time or from time to time before the termination of the lock-up period, without notice, release all or any portion of the securities subject to lock-up agreements.

Price Stabilization, Short Positions and Penalty Bids

In connection with the offering the underwriters may engage in stabilizing transactions, over-allotment transactions, syndicate covering transactions and penalty bids in accordance with Regulation M under the Exchange Act:

• Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum.

• Over-allotment involves sales by the underwriters of shares in excess of the number of shares the underwriters are obligated to purchase, which creates a syndicate short position. The short position may be either a covered short position or a naked short position. In a covered short position, the number of shares over-allotted by the underwriters is not greater than the number of shares that they may purchase in the over-allotment option. In a naked short position, the number of shares involved is greater than the number of shares in the over-allotment option. The underwriters may close out any covered short position by either exercising their over-allotment option and/or purchasing shares in the open market.

• Syndicate covering transactions involve purchases of shares of the common stock in the open market after the distribution has been completed in order to cover syndicate short positions. In determining the source of shares to close out the short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which it may purchase shares through the over-allotment option. If the underwriters sell more shares than could be covered by the over-allotment option, a naked short position, the position can only be closed out by buying shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there could be downward pressure on the price of the shares in the open market after pricing that could adversely affect investors who purchase in the offering.

S-11

• Penalty bids permit the representative to reclaim a selling concession from a syndicate member when the common stock originally sold by the syndicate member is purchased in a stabilizing or syndicate covering transaction to cover syndicate short positions.

These stabilizing transactions, syndicate covering transactions and penalty bids may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of the common stock. As a result, the price of our common stock may be higher than the price that might otherwise exist in the open market. Neither we nor the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of the common stock. In addition, neither we nor the underwriters make any representations that the underwriters will engage in these stabilizing transactions or that any transaction, once commenced, will not be discontinued without notice.

Passive Market Making

In connection with this offering, the underwriters and any selling group members may engage in passive market making transactions in our common stock on The NASDAQ Stock Market in accordance with Rule 103 of Regulation M under the Securities Exchange Act of 1934, as amended, during a period before the commencement of offers or sales of common stock and extending through the completion of the distribution. A passive market maker must display its bid at a price not in excess of the highest independent bid of that security. However, if all independent bids are lowered below the passive market maker’s bid, that bid must then be lowered when specified purchase limits are exceeded.

Listing and Transfer Agent

Our common stock is listed on The NASDAQ Capital Market and trades under the symbol “TGTX.” The transfer agent of our common stock is American Stock Transfer and Trust Company.

Electronic Distribution

This prospectus supplement and the accompanying prospectus in electronic format may be made available on websites or through other online services maintained by one or more of the underwriters, or by their affiliates. Other than this prospectus supplement and the accompanying prospectus in electronic format, the information on any underwriter’s website and any information contained in any other website maintained by an underwriter is not part of this prospectus supplement, the accompanying prospectus or the registration statement of which this prospectus supplement and the accompanying prospectus forms a part, has not been approved and/or endorsed by us or any underwriter in its capacity as underwriter, and should not be relied upon by investors.

Other

From time to time, certain of the underwriters and/or their affiliates have provided, and may in the future provide, various investment banking and other financial services for us for which services they have received and, may in the future receive, customary fees. In the course of their businesses, the underwriters and their affiliates may actively trade our securities or loans for their own account or for the accounts of customers, and, accordingly, the underwriters and their affiliates may at any time hold long or short positions in such securities or loans. Except for services provided in connection with this offering, no underwriter has provided any investment banking or other financial services during the 180-day period preceding the date of this prospectus supplement and we do not expect to retain any underwriter to perform any investment banking or other financial services for at least 90 days after the date of this prospectus supplement.

S-12

Notice to Investors

Notice to Investors in the United Kingdom

In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a “Relevant Member State”) an offer to the public of any securities which are the subject of the offering contemplated by this prospectus supplement and the accompanying prospectus may not be made in that Relevant Member State except that an offer to the public in that Relevant Member State of any such securities may be made at any time under the following exemptions under the Prospectus Directive, if they have been implemented in that Relevant Member State:

(a) to legal entities which are authorized or regulated to operate in the financial markets or, if not so authorized or regulated, whose corporate purpose is solely to invest in securities;

(b) to any legal entity which has two or more of (1) an average of at least 250 employees during the last financial year; (2) a total balance sheet of more than €43,000,000 and (3) an annual net turnover of more than €50,000,000, as shown in its last annual or consolidated accounts;

(c) by the underwriters to fewer than 100 natural or legal persons (other than qualified investors as defined in the Prospectus Directive); or

(d) in any other circumstances falling within Article 3(2) of the Prospectus Directive, provided that no such offer of these securities shall result in a requirement for the publication by the issuer or the underwriter of a prospectus pursuant to Article 3 of the Prospectus Directive.

For the purposes of this provision, the expression an “offer to the public” in relation to any of the securities in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and any such securities to be offered so as to enable an investor to decide to purchase any such securities, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State and the expression “Prospectus Directive” means Directive 2003/71/EC and includes any relevant implementing measure in each Relevant Member State.

Each underwriter has represented, warranted and agreed that:

(a) it has only communicated or caused to be communicated and will only communicate or cause to be communicated any invitation or inducement to engage in investment activity (within the meaning of section 21 of the Financial Services and Markets Act 2000 (the FSMA)) received by it in connection with the issue or sale of any of the securities in circumstances in which section 21(1) of the FSMA does not apply to the issuer; and

(b) it has complied with and will comply with all applicable provisions of the FSMA with respect to anything done by it in relation to the securities in, from or otherwise involving the United Kingdom.

European Economic Area

In particular, this document does not constitute an approved prospectus in accordance with European Commission’s Regulation on Prospectuses no. 809/2004 and no such prospectus is to be prepared and approved in connection with this offering. Accordingly, in relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (being the Directive of the European Parliament and of the Council 2003/71/EC and including any relevant implementing measure in each Relevant Member State) (each, a Relevant Member State), with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State (the Relevant Implementation Date) an offer of securities to the public may not be made in that Relevant Member State prior to the publication of a prospectus in relation to such securities which has been approved by the competent authority in that Relevant Member State or, where appropriate, approved in another Relevant Member State and notified to the competent authority in that Relevant Member State, all in accordance with the Prospectus Directive, except that it may, with effect from and including the Relevant Implementation Date, make an offer of securities to the public in that Relevant Member State at any time:

• to legal entities which are authorized or regulated to operate in the financial markets or, if not so authorized or regulated, whose corporate purpose is solely to invest in securities;

S-13

• to any legal entity which has two or more of (1) an average of at least 250 employees during the last financial year; (2) a total balance sheet of more than €43,000,000; and (3) an annual net turnover of more than €50,000,000, as shown in the last annual or consolidated accounts; or

• in any other circumstances which do not require the publication by the Issuer of a prospectus pursuant to Article 3 of the Prospectus Directive.

For the purposes of this provision, the expression an “offer of securities to the public” in relation to any of the securities in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the securities to be offered so as to enable an investor to decide to purchase or subscribe for the securities, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State. For these purposes the shares offered hereby are “securities.”

S-14

Legal Matters

Alston & Bird LLP, New York, New York, has passed upon the validity of the shares offered by this prospectus supplement. Certain legal matters will be passed upon for the underwriters by Lowenstein Sandler LLP, New York, New York.

Experts

The consolidated financial statements of TG Therapeutics, Inc. and subsidiaries as of December 31, 2012 and 2011 and for the years then ended, and the cumulative period ended December 31, 2012 have been incorporated by reference herein in reliance upon the report of CohnReznick LLP, independent registered public accounting firm, and upon the authority of said firm as experts in accounting and auditing.

Where You Can Find More Information

We file annual, quarterly and current reports, proxy statements, and other information with the SEC. You may read and copy any documents we have filed with the SEC at its Public Reference Room located at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. We also file these documents with the SEC electronically. You can access the electronic versions of these filings on the SEC’s Internet website found at http://www.sec.gov. You can also obtain copies of materials we file with the SEC, free of charge, from our Internet website found at www.tgtherapeutics.com. Information contained on our website does not constitute part of this prospectus supplement or the accompanying prospectus. Our stock is quoted on The NASDAQ Capital Market under the symbol “TGTX.”

Incorporation of Certain Information by Reference

The SEC allows us to “incorporate by reference” the information we file with them which means that we can disclose important information to you by referring you to those documents instead of having to repeat the information in this prospectus supplement and accompanying prospectus. The information incorporated by reference is considered to be part of this prospectus supplement and accompanying prospectus, and later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings made with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act between the date of this prospectus supplement and the termination of the offering (other than, unless otherwise specifically indicated, current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items):

• Our Annual Report on Form 10-K for the year ended December 31, 2012 as amended by Form 10K/A filed with the SEC on June 10, 2013 ;

• Our Quarterly Report on Form 10-Q for the quarter ended March 31, 2013;

• Our Current Reports on Form 8-K filed with the SEC on January 3, 2013, January 22, 2013, May 28, 2013, June 3, 2013, June 6, 2013, June 21, 2013 and July 18, 2013;

• Our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 24, 2013; and

• The description of our common stock contained in our registration statement on Form 8-A filed with the SEC on May 28, 2013 (File No. 001-32639).

We also incorporate by reference all documents we file under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act until all of the common stock to which this prospectus supplement and the accompanying prospectus relates has been sold or the offering is otherwise terminated.

S-15

PROSPECTUS

$175,000,000

TG Therapeutics, Inc.

Common Stock

We may offer and sell an indeterminate number of shares of our common stock from time to time under this prospectus. You should read this prospectus and any prospectus supplement carefully before you invest.

We may offer our common stock in one or more offerings in amounts, at prices, and on terms determined at the time of the offering. We may sell our common stock through agents we select or through underwriters and dealers we select. If we use agents, underwriters or dealers, we will name them and describe their compensation in a prospectus supplement.

This prospectus provides a general description of the securities we may offer. Each time we sell securities, we will provide specific terms of the securities offered in a supplement to this prospectus. The prospectus supplement may also add, update or change information contained in this prospectus. You should read this prospectus and the applicable prospectus supplement carefully before you invest in any securities. This prospectus may not be used to consummate a sale of securities unless accompanied by the applicable prospectus supplement.

Our common stock is traded on the NASDAQ Capital Market under the symbol “TGTX.” On May 30, 2013, the per share closing price of our common stock as reported on the NASDAQ Capital Market was $6.25 per share.

Investing in our securities involves certain risks. See “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2012, as well as our Quarterly Report on Form 10-Q for the period ended March 31, 2013, which has been filed with the SEC and is incorporated by reference into this prospectus. You should read the entire prospectus carefully before you make your investment decision.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is June 17, 2013.

Table of Contents

	Page
TG Therapeutics, Inc.		1
The Offering		1
Where You Can Find More Information		1
Important Information About This Prospectus		2
Incorporation of Certain Information by Reference		2
Description of Common Stock		3
Plan of Distribution		4
Legal Matters		5
Experts		5

i

TG THERAPEUTICS, INC.

We are a biopharmaceutical company focused on the acquisition, development and commercialization of innovative and medically important pharmaceutical products for the treatment of cancer and other underserved therapeutic needs. We aim to acquire rights to these technologies by licensing or otherwise acquiring an ownership interest, funding their research and development and eventually either out-licensing or bringing the technologies to market.

Currently, the Company is developing two therapies targeting hematological malignancies. TG-1101 (ublituximab) is a novel, third generation monoclonal antibody that targets a specific and unique epitope on the CD20 antigen found on mature B-lymphocytes. We are also developing TGR-1202, an orally available PI3K delta inhibitor.

We also actively evaluate complementary products, technologies and companies for in-licensing, partnership, acquisition and/or investment opportunities. To date, we have not received approval for the sale of any of our drug candidates in any market and, therefore, have not generated any product sales from our drug candidates.

Our principal executive offices are located at 787 Seventh Avenue, New York, New York 10019, and our telephone number is 212-554-4484. We maintain a website on the Internet at www.tgtherapeutics.com and our e-mail address is info@tgtxinc.com. Our Internet website, and the information contained on it, are not to be considered part of this prospectus.

THE OFFERING

Use of Proceeds	We intend to use the net proceeds of any offering as set forth in the applicable prospectus supplement.
Nasdaq Symbol	TGTX

WHERE YOU CAN FIND MORE INFORMATION

We file reports with the SEC on an annual basis using Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K. You may read and copy any such reports and amendments thereto at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549 on official business days during the hours of 10:00 a.m. to 3:00 p.m. Please call the SEC at 1-800-SEC-0330 for information on the Public Reference Room. Additionally, the SEC maintains a website that contains annual, quarterly, and current reports, proxy statements, and other information that issuers (including us) file electronically with the SEC. The SEC’s website address is http://www.sec.gov. You can also obtain copies of materials we file with the SEC from our Internet website found at www.tgtherapeutics.com. Our stock is quoted on the NASDAQ Capital Market under the symbol “TGTX.”

1

IMPORTANT INFORMATION ABOUT THIS PROSPECTUS

This prospectus is part of a “shelf” registration statement that we filed with the SEC. By using a shelf registration statement, we may sell our securities, as described in this prospectus, from time to time in one or more offerings. We may use the shelf registration statement to offer and sell securities described in this prospectus. Each time we sell securities, we will provide a prospectus supplement to this prospectus that contains specific information about the terms of such offering. The supplement may also add, update or change information contained in this prospectus. Before purchasing any securities, you should carefully read both this prospectus and any supplement, together with the additional information incorporated into this prospectus or described under the heading “Where You Can Find More Information.”

You should rely only on the information contained or incorporated by reference in this prospectus and any prospectus supplement. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We will not make an offer to sell securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus, as well as information we previously filed with the SEC and have incorporated by reference, is accurate as of the date on the front cover of this prospectus only, or when such document was filed with the SEC. Our business, financial condition, results of operations and prospects may have changed since the relevant date.

We will not use this prospectus to offer and sell securities unless it is accompanied by a prospectus supplement that more fully describes the terms of the offering.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” into this prospectus the information we file with the SEC. This means that we can disclose important information to you by referring you to those documents without restating that information in this document. The information incorporated by reference into this prospectus is considered to be part of this prospectus, and information we file with the SEC pursuant to Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act, after the date of this prospectus and prior to the termination of this offering, will automatically update and supersede the information contained in this prospectus and documents listed below. We incorporate by reference into this prospectus the documents listed below, except to the extent information in those documents differs from information contained in this prospectus, and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, including exhibits:

(a) Our Annual Report on Form 10-K for the year ended December 31, 2012;

(b) Our Quarterly Report on Form 10-Q for the quarter ended March 31, 2013;

(c) Our Current Reports on Form 8-K filed with the SEC on May 14, 2013 and May 28, 2013;

(d) Our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 24, 2013 and

(e) The description of our common stock contained in our registration statement on Form 8-A filed with the SEC on May 28, 2013 (File No. 001-32639).

We will provide to each person, including any beneficial owner, to whom a copy of this prospectus is delivered, a copy of any or all of the information that we have incorporated by reference into this prospectus. We will provide this information upon written or oral request at no cost to the requester. You may request this information by contacting our corporate headquarters at the following address: 787 Seventh Avenue, New York, New York 10019, Attn: Chief Financial Officer, or by calling (212) 554-4484.

2

DESCRIPTION OF COMMON STOCK

The following summary of the terms of our common stock may not be complete and is subject to, and qualified in its entirety by reference to, the terms and provisions of our amended and restated certificate of incorporation and our restated bylaws. You should refer to, and read this summary together with, our amended and restated certificate of incorporation and restated bylaws to review all of the terms of our common stock that may be important to you.

Common Stock

Under our certificate of incorporation, we are authorized to issue a total of 500,000,000 shares of common stock, par value $0.001 per share. As of December 31, 2012 we had issued and outstanding 25,820,738 shares of our common stock. There are approximately 234 holders of record. All outstanding shares of our common stock are fully paid and nonassessable. Our common stock is listed on the NASDAQ Capital Market under the symbol “TGTX.”

Dividends

Subject to the dividend rights of the holders of any outstanding series of preferred stock, holders of our common stock are entitled to receive ratably such dividends and other distributions of cash or any other right or property as may be declared by our board of directors out of our assets or funds legally available for such dividends or distributions.

Voting Rights

The holders of our common stock are entitled to one vote for each share of common stock owned by that stockholder on every matter properly submitted to the stockholders for their vote. Stockholders are not entitled to vote cumulatively for the election of directors.

Liquidation and Dissolution

In the event of any voluntary or involuntary liquidation, dissolution or winding up of our affairs, holders of common stock would be entitled to share ratably in our assets that are legally available for distribution to stockholders after payment of liabilities. If we have any preferred stock outstanding at such time, holders of the preferred stock may be entitled to distributions and/or liquidation preferences. In either such case, we must pay the applicable distribution to the holders of our preferred stock (if any) before we may pay distributions to the holders of common stock.

Other

Holders of our common stock have no conversion, redemption, preemptive, subscription or similar rights.

Transfer Agent

American Stock Transfer and Trust Company serves as the transfer agent and registrar for all of our common stock.

3

PLAN OF DISTRIBUTION

We may sell the securities covered in this prospectus in any of three ways (or in any combination):

• through underwriters or dealers;

• directly to a limited number of purchasers or to a single purchaser; or

• through agents.

Each time that we use this prospectus to sell securities, we will also provide a prospectus supplement that contains the specific terms of the offering. The prospectus supplement will set forth the terms of the offering of the securities, including:

• the name or names of any underwriters, dealers or agents and the amounts of any securities underwritten or purchased by each of them; and

• the public offering price of the common stock and the proceeds to us and any discounts, commissions or concessions allowed or reallowed or paid to dealers.

Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

If underwriters are used in the sale of any securities, the securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The securities may be either offered to the public through underwriting syndicates represented by managing underwriters, or directly by underwriters. Generally, the underwriters’ obligations to purchase the securities will be subject to certain conditions precedent. The underwriters will be obligated to purchase all of the securities if they purchase any of securities.

We may sell the securities through agents from time to time. The prospectus supplement will name any agent involved in the offer or sale of the securities and any commissions we pay to them. Generally, any agent will be acting on a best efforts basis for the period of its appointment.

We may authorize underwriters, dealers or agents to solicit offers by certain purchasers to purchase the securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. The contracts will be subject only to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth any commissions we pay for solicitation of these contracts.

Agents and underwriters may be entitled to indemnification by us against certain civil liabilities, including liabilities under the Securities Act of 1933, as amended, or to contribution with respect to payments which the agents or underwriters may be required to make in respect thereof. Agents and underwriters may be customers of, engage in transactions with, or perform services for us in the ordinary course of business.

We may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of securities, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of securities. The third party in such sale transactions will be an underwriter and will be identified in the applicable prospectus supplement (or a post-effective amendment).

In compliance with the guidelines of the Financial Services Regulatory Authority, Inc., or FINRA, the maximum compensation to be received by a FINRA member or independent broker-dealer may not exceed 8% of the offering proceeds. It is anticipated that the maximum compensation to be received in any particular offering of securities will be less than this amount.

4

LEGAL MATTERS

The legality and validity of the securities offered from time to time under this prospectus will be passed upon by Alston & Bird LLP, New York, New York.

EXPERTS

The consolidated financial statements of TG Therapeutics, Inc. and Subsidiaries as of December 31, 2012 and 2011, and for the years then ended, and the cumulative period ended December 31, 2012, have been incorporated by reference herein and in the registration statement in reliance upon the report of CohnReznick LLP, independent registered public accounting firm, and upon the authority of said firm as experts in accounting and auditing.

5

$35,055,000

TG Therapeutics, Inc.

Common Stock

 

PROSPECTUS SUPPLEMENT

 

Roth Capital Partners	Ladenburg Thalmann & Co. Inc.	Brean Capital

     National Securities Corporation

July 18, 2013