10-Q

United States
Securities and Exchange Commission

Washington, D.C. 20549

Form 10-Q

(Mark One)

þ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2011

o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from                      to                     

Commission file number 000-50700

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership

(Name of small business issuer in its charter)

Delaware (State or other jurisdiction of incorporation or organization)	54-2113989 (I.R.S. Employer Identification No.)
Westpointe Corporate Center One 1550 Coraopolis Heights Rd. 2nd Floor
Moon Township, PA	15108
(Address of principal executive offices)	(zip code)

Issuer’s telephone number, including area code: (412) 262-2830

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15 (d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes þ No o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes o No o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer,” “non accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act (Check one):

Large accelerated filer o Accelerated filer o Non-accelerated filer o Smaller reporting company þ

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o No þ

Transitional Small Business Disclosure Format (check one): Yes o No þ

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership
(A Delaware Limited Partnership)
INDEX TO QUARTERLY REPORT
ON FORM 10-Q

	PAGE
PART I. FINANCIAL INFORMATION
Item 1: Financial Statements
Balance Sheets as of March 31, 2011 and December 31, 2010		3
Statements of Operations for the Three Months Ended March 31, 2011 and 2010		4
Statement of Changes in Partners’ Capital for the Three Months ended March 31, 2011		5
Statements of Cash Flows for the Three Months ended March 31, 2011 and 2010		6
Notes to Financial Statements		7-14
Item 2: Management’s Discussion and Analysis of Financial Condition or Plan of Operations		15-18
Item 4: Controls and Procedures		18
PART II. OTHER INFORMATION
Item 1: Legal Proceedings		18
Item 6: Exhibits		19
SIGNATURES		20
CERTIFICATIONS
Exhibit 31.1
Exhibit 31.2
Exhibit 32.1
Exhibit 32.2

2

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership

BALANCE SHEETS

	March 31,			December 31,
	2011			2010
	(Unaudited)
ASSETS
Current assets:
Cash and cash equivalents		131,100		$	152,500
Accounts receivable-affiliate		618,100			401,800
Short-term hedge receivable due from affiliate		—			380,300
Total current assets		749,200			934,600
Oil and gas properties, net		6,107,000			6,218,100
Long-term hedge receivable due from affiliate		—			371,400
Long-term receivable due from affiliate		271,000			—
	$	7,127,200		$	7,524,100
LIABILITIES AND PARTNERS’ CAPITAL
Current liabilities:
Accrued liabilities	$	13,500		$	13,200
Short-term hedge liability due to affiliate		—			1,600
Total current liabilities		13,500			14,800
Asset retirement obligation		3,146,900			3,100,400
Long-term hedge liability due to affiliate		—			63,400
Partners’ capital:
Managing general partner		5,128,400			5,428,400
Limited partners (4,024 units)		(1,382,300	)		(1,131,000	)
Accumulated other comprehensive income		220,700			48,100
Total partners’ capital		3,966,800			4,345,500
	$	7,127,200		$	7,524,100

See accompanying notes to financial statements.

3

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership

STATEMENTS OF OPERATIONS
(Unaudited)

	Three Months Ended
	March 31,
	2011			2010
REVENUES
Natural gas and oil	$	353,900		$	543,300
Interest income		100			100
Total revenues		354,000			543,400
COSTS AND EXPENSES
Production		272,700			321,200
Depletion		111,100			227,600
Accretion of asset retirement obligation		46,500			36,900
General and administrative		58,300			56,500
Total costs and expenses		488,600			642,200
Net loss	$	(134,600	)	$	(98,800	)
Allocation of net loss:
Managing general partner	$	(34,400	)	$	12,900
Limited partners	$	(100,200	)	$	(111,700	)
Net loss per limited partnership unit	$	(25	)	$	(28	)

See accompanying notes to financial statements.

4

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership

STATEMENT OF CHANGES IN PARTNERS’ CAPITAL
FOR THE THREE MONTHS ENDED

March 31, 2011
(Unaudited)

							Accumulated
	Managing						Other
	General			Limited			Comprehensive
	Partner			Partners			Income		Total
Balance at January 1, 2011	$	5,428,400		$	(1,131,000	)	$	48,100	$	4,345,500
Participation in revenues and expenses:
Net production revenues		18,500			62,700			—		81,200
Interest income		—			100			—		100
Depletion		(16,300	)		(94,800	)		—		(111,100	)
Accretion of asset retirement obligation		(16,300	)		(30,200	)		—		(46,500	)
General and administrative		(20,300	)		(38,000	)		—		(58,300	)
Net loss		(34,400	)		(100,200	)		—		(134,600	)
Other comprehensive income		—			—			172,600		172,600
Distributions to partners		(265,600	)		(151,100	)		—		(416,700	)
Balance at March 31, 2011	$	5,128,400		$	(1,382,300	)	$	220,700	$	3,966,800

See accompanying notes to financial statements.

5

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership

STATEMENTS OF CASH FLOWS
(Unaudited)

	Three Months Ended
	March 31,
	2011			2010
Cash flows from operating activities:
Net loss	$	(134,600	)	$	(98,800	)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depletion		111,100			227,600
Non-cash loss on derivative value		112,400			119,600
Accretion of asset retirement obligation		46,500			36,900
Decrease (increase) in accounts receivable — affiliate		75,400			(4,300	)
Increase (decrease) in accrued liabilities		300			(6,900	)
Net cash provided by operating activities		211,100			274,100
Cash flows from financing activities:
Distributions to partners		(232,500	)		(263,900	)
Net cash used in financing activities		(232,500	)		(263,900	)
Net (decrease) increase in cash and cash equivalents		(21,400	)		10,200
Cash and cash equivalents at beginning of period		152,500			175,000
Cash and cash equivalents at end of period	$	131,100		$	185,200
Supplemental Schedule of non-cash operating and financing activities:
Distribution to managing general partner	$	184,200		$	—

See accompanying notes to financial statements.

6

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership

NOTES TO FINANCIAL STATEMENTS
March 31, 2011

(Unaudited)

NOTE 1 — DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION

Atlas America Public #12-2003 Limited Partnership (the “Partnership”) is a Delaware limited partnership formed on July 15, 2003 with Atlas Resources, LLC serving as its Managing General Partner and operator (“Atlas Resources” or “MGP”). Atlas Resources is an indirect subsidiary of Atlas Energy, L.P., formerly Atlas Pipeline Holdings, L.P. (“Atlas Energy”) (NYSE: ATLS). On February 17, 2011, Atlas Energy, a then-majority owned subsidiary of Atlas Energy, Inc. and parent of the general partner of Atlas Pipeline Partners, L.P. (“APL”) (NYSE: APL), completed an acquisition of assets from Atlas Energy, Inc., which included its investment partnership business; its oil and gas exploration, development and production activities conducted in Tennessee, Indiana, and Colorado, certain shallow wells and leases in New York and Ohio, and certain well interests in Pennsylvania and Michigan; and its ownership and management of investments in Lightfoot Capital Partners, L.P. and related entities.

Atlas Resources’ focus is on the development and/or production of natural gas and oil in the Appalachian, Michigan, Illinois, and/or Colorado basin regions of the United States of America. Atlas Resources is also a leading sponsor of and manages tax-advantaged direct investment partnerships, in which it co-invests to finance the exploitation and development of its acreage. Atlas Energy Resource Services, Inc. provides Atlas Resources with the personnel necessary to manage its assets and raise capital.

The accompanying financial statements, which are unaudited except that the balance sheets at December 31, 2010, is derived from audited financial statements, are presented in accordance with the requirements of Form 10-Q and accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim reporting. They do not include all disclosures normally made in financial statements contained in the Form 10-K. These interim financial statements should be read in conjunction with the audited financial statements and notes thereto presented in the Partnership’s Annual Report on Form 10-K for the year ended December 31, 2010. The results of operations for the three months ended March 31, 2011 may not necessarily be indicative of the results of operations for the year ended December 31, 2011.

NOTE 2 — SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

In management’s opinion, all adjustments necessary for a fair presentation of the Partnership’s financial position, results of operations and cash flows for the periods disclosed have been made. Management has considered for disclosure any material subsequent events through the date the financial statements were issued.

In addition to matters discussed further in this note, the Partnership’s significant accounting policies are detailed in its audited financial statements and notes thereto in the Partnership’s annual report on Form 10-K for the year ended December 31, 2010 filed with the Securities and Exchange Commission (“SEC”).

Use of Estimates

Preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities that exist at the date of the Partnership’s financial statements, as well as the reported amounts of revenue and costs and expenses during the reporting periods. The Partnership’s financial statements are based on a number of significant estimates, including the revenue and expense accruals, depletion, asset impairments, fair value of derivative instruments and the probability of forecasted transactions. Actual results could differ from those estimates.

7

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership
NOTES TO FINANCIAL STATEMENTS (Continued)
March 31, 2011
(Unaudited)

NOTE 2 — SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

Use of Estimates (Continued)

The natural gas industry principally conducts its business by processing actual transactions as much as 60 days after the month of delivery. Consequently, the most recent two months’ financial results were recorded using estimated volumes and contract market prices. Differences between estimated and actual amounts are recorded in the following months’ financial results. Management believes that the operating results presented for the three months ended March 31, 2011 and 2010 represent actual results in all material respects (see “Revenue Recognition” accounting policy for further description).

Accounts Receivable and Allowance for Possible Losses

In evaluating the need for an allowance for possible losses, the Partnership’s MGP performs ongoing credit evaluations of its customers and adjusts credit limits based upon payment history and the customer’s current creditworthiness, as determined by review of its customers’ credit information. Credit is extended on an unsecured basis to many of its energy customers. At March 31, 2011 and December 31, 2010, the Partnership’s MGP’s credit evaluation indicated that the Partnership had no need for an allowance for possible losses.

Oil and Gas Properties

Oil and gas properties are stated at cost. Maintenance and repairs are expensed as incurred. Major renewals and improvements that extend the useful lives of property are capitalized. The Partnership follows the successful efforts method of accounting for oil and gas producing activities. Oil is converted to gas equivalent basis (“Mcfe”) at the rate of one barrel equals 6 Mcf.

The Partnership’s depletion expense is determined on a field-by-field basis using the units-of-production method. Depletion rates for lease, well and related equipment costs are based on proved developed reserves associated with each field. Depletion rates are determined based on reserve quantity estimates and the capitalized costs of developed producing properties. Upon the sale or retirement of a complete field of a proved property, the Partnership eliminates the cost from the property accounts and the resultant gain or loss is reclassified to the Partnership’s statements of operations. Upon the sale of an individual well, the Partnership credits the proceeds to accumulated depreciation and depletion within its balance sheets.

	March 31,			December 31,
	2011			2010
Proved properties:
Leasehold interests	$	1,131,600		$	1,131,600
Wells and related equipment		52,145,600			52,145,600
		53,277,200			53,277,200
Accumulated depletion		(47,170,200	)		(47,059,100	)
	$	6,107,000		$	6,218,100

8

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership
NOTES TO FINANCIAL STATEMENTS (Continued)
March 31, 2011
(Unaudited)

NOTE 2 — SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

Impairment of Long-Lived Assets

The Partnership reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If it is determined that an asset’s estimated future cash flows will not be sufficient to recover its carrying amount, an impairment charge will be recorded to reduce the carrying amount for that asset to its estimated fair value if such carrying amount exceeds the fair value.

The review of the Partnership’s oil and gas properties is done on a field-by-field basis by determining if the historical cost of proved properties, less the applicable accumulated depletion, and abandonment is less than the estimated expected undiscounted future cash flows. The expected future cash flows are estimated based on the Partnership’s plans to continue to produce and develop proved reserves. Expected future cash flow from the sale of production of reserves is calculated based on estimated future prices. The Partnership estimates prices based upon current contracts in place, adjusted for basis differentials and market related information including published futures prices. The estimated future level of production is based on assumptions surrounding future prices and costs, field decline rates, market demand and supply and the economic and regulatory climates. If the carrying value exceeds the expected future cash flows, an impairment loss is recognized for the difference between the estimated fair market value (as determined by discounted future cash flows) and the carrying value of the assets.

The determination of oil and natural gas reserve estimates is a subjective process and the accuracy of any reserve estimate depends on the quality of available data and the application of engineering and geological interpretation and judgment. Estimates of economically recoverable reserves and future net cash flows depend on a number of variable factors and assumptions that are difficult to predict and may vary considerably from actual results. In addition, reserve estimates for wells with limited or no production history are less reliable than those based on actual production. Estimated reserves are often subject to future revisions, which could be substantial, based on the availability of additional information which could cause the assumptions to be modified. The Partnership cannot predict what reserve revisions may be required in future periods. There was no impairment charge recognized during the three months ended March 31, 2011. During the year ended December 31, 2010, the Partnership recognized an impairment charge of $3,667,800, net of an offsetting gain in accumulated other comprehensive income of $323,000.

Working Interest

The Partnership Agreement establishes that revenues and expenses will be allocated to the MGP and limited partners based on their ratio of capital contributions to total contributions (“working interest”). The MGP is also provided an additional working interest of 7% as provided in the Partnership Agreement. Due to the time necessary to complete drilling operations and accumulate all drilling costs, estimated working interest percentage ownership rates are utilized to allocate revenues and expenses until the wells are completely drilled and turned on-line into production. Once the wells are completed, the final working interest ownership of the partners is determined and any previously allocated revenues and expenses based on the estimated working interest percentage ownership are adjusted to conform to the final working interest percentage ownership.

9

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership
NOTES TO FINANCIAL STATEMENTS (Continued)
March 31, 2011
(Unaudited)

NOTE 2 — SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

Revenue Recognition

The Partnership generally sells natural gas and crude oil at prevailing market prices. Revenue is recognized when produced quantities are delivered to a custody transfer point, persuasive evidence of a sales arrangement exists, the rights and responsibility of ownership pass to the purchaser upon delivery, collection of revenue from the sale is reasonably assured and the sales price is fixed or determinable. Revenues from the production of natural gas and crude oil in which the Partnership has an interest with other producers are recognized on the basis of the Partnership’s percentage ownership of working interest. Generally, the Partnership’s sales contracts are based on pricing provisions that are tied to a market index with certain adjustments based on proximity to gathering and transmission lines and the quality of its natural gas.

The Partnership accrues unbilled revenue due to timing differences between the delivery of natural gas and crude oil and the receipt of a delivery statement. These revenues are recorded based upon volumetric data from the Partnership’s records and management estimates of the related commodity sales and transportation fees which are, in turn, based upon applicable product prices (see “Use of Estimates” accounting policy for further description). The Partnership had unbilled revenues at March 31, 2011 and December 31, 2010 of $236,700 and $294,800, respectively, which are included in accounts receivable — affiliate within the Partnership’s balance sheets.

Recently Adopted Accounting Standards

As of the date of this filing, there are no newly issued accounting standards which impacted the presentation of the attached financial statements that have not already been adopted.

NOTE 3 — ASSET RETIREMENT OBLIGATION

The Partnership recognizes an estimated liability for the plugging and abandonment of its oil and gas wells and related facilities. It also recognizes a liability for future asset retirement obligations if a reasonable estimate of the fair value of that liability can be made. The associated asset retirement costs are capitalized as part of the carrying amount of the long-lived asset. The Partnership also considers the estimated salvage value in the calculation of depletion.

The estimated liability is based on the MGP’s historical experience in plugging and abandoning wells, estimated remaining lives of those wells based on reserve estimates, external estimates as to the cost to plug and abandon the wells in the future and federal and state regulatory requirements. The liability is discounted using an assumed credit-adjusted risk-free interest rate. Revisions to the liability could occur due to changes in estimates of plugging and abandonment costs or remaining lives of the wells or if federal or state regulators enact new plugging and abandonment requirements. The Partnership has no assets legally restricted for purposes of settling asset retirement obligations. Except for its oil and gas properties, the Partnership has determined that there are no other material retirement obligations associated with tangible long-lived assets.

	Three Months Ended
	March 31,
	2011		2010
Asset retirement obligation at beginning of period	$	3,100,400	$	2,457,900
Accretion expense		46,500		36,900
Asset retirement obligation at end of period	$	3,146,900	$	2,494,800

10

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership
NOTES TO FINANCIAL STATEMENTS (Continued)
March 31, 2011
(Unaudited)

NOTE 4 — COMPREHENSIVE INCOME

Comprehensive income includes net loss and all other changes in equity of a business during a period from transactions and other events and circumstances from non-owner sources that, under accounting principles generally accepted in the United States of America, have not been recognized in the calculation of net loss. These changes, other than net loss, are referred to as “other comprehensive income” and, for the Partnership, include changes in the fair value of unsettled derivative contracts accounted for as cash flow hedges. A reconciliation of the Partnership’s comprehensive income for the periods indicated is as follows:

	Three Months Ended
	March 31,
	2011			2010
Net loss	$	(134,600	)	$	(98,800	)
Other comprehensive income:
Unrealized holding gains on hedging contracts		241,700			654,100
Less: reclassification adjustment for gains realized in net loss		(69,100	)		(34,800	)
Total other comprehensive income		172,600			619,300
Comprehensive income	$	38,000		$	520,500

NOTE 5 — DERIVATIVE INSTRUMENTS

The MGP, on behalf of the Partnership, uses a number of different derivative instruments, principally swaps and collars, in connection with its commodity price risk management activities. The MGP enters into financial instruments to hedge the Partnership’s forecasted natural gas and crude oil against the variability in expected future cash flows attributable to changes in market prices. Swap instruments are contractual agreements between counterparties to exchange obligations of money as the underlying natural gas and crude oil is sold. Under swap agreements, the Partnership receives or pays a fixed price and receives or remits a floating price based on certain indices for the relevant contract period. Commodity-based option instruments are contractual agreements that grant the right, but not obligation, to purchase or sell natural gas and crude oil at a fixed price for the relevant contract period.

Historically, the MGP has entered into natural gas and crude oil future option contracts and collar contracts on behalf of the Partnership to achieve more predictable cash flows by hedging its exposure to changes in natural gas and oil prices. At any point in time, such contracts may include regulated New York Mercantile Exchange (“NYMEX”) futures and options contracts and non-regulated over-the-counter futures contracts with qualified counterparties. NYMEX contracts are generally settled with offsetting positions, but may be settled by the delivery of natural gas. Crude oil contracts are based on a West Texas Intermediate (“WTI”) index. These contracts have qualified and been designated as cash flow hedges and recorded at their fair values.

11

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership
NOTES TO FINANCIAL STATEMENTS (Continued)
March 31, 2011
(Unaudited)

NOTE 5 — DERIVATIVE INSTRUMENTS (Continued)

The MGP formally documents all relationships between hedging instruments and the items being hedged, including its risk management objective and strategy for undertaking the hedging transactions. This includes matching the commodity derivative contracts to the forecasted transactions. The MGP assesses, both at the inception of the derivative and on an ongoing basis, whether the derivative is effective in offsetting changes in the forecasted cash flow of the hedged item. If it is determined that a derivative is not effective as a hedge or that it has ceased to be an effective hedge due to the loss of adequate correlation between the hedging instrument and the underlying item being hedged, the MGP will discontinue hedge accounting for the derivative and subsequent changes in the derivative fair value, which is determined by the MGP through the utilization of market data, will be recognized immediately within gain (loss) on mark-to-market derivatives in the Partnership’s statements of operations. For derivatives qualifying as hedges, the Partnership recognizes the effective portion of changes in fair value in partners’ capital as accumulated other comprehensive income and reclassifies the portion relating to commodity derivatives to gas and oil production revenues for the Partnership’s derivatives within the Partnership’s statements of operations as the underlying transactions are settled. For non-qualifying derivatives and for the ineffective portion of qualifying derivatives, the Partnership recognizes changes in fair value within gain (loss) on mark-to-market derivatives in its statements of operations as they occur.

Prior to the acquisition on February 17, 2011 (“the Transferred Business”), ATLS monetized its derivative instruments related to the Transferred Business. The monetized proceeds relate to instruments that were originally put into place to hedge future natural gas and oil production of the Transferred Business, including production generated through its Drilling Partnerships. At March 31, 2011, the Partnership recorded a net receivable from the monetized derivative instruments of $291,700 in accounts receivable-affiliate and $271,000 in long-term receivable-affiliate with the corresponding net unrealized gains in accumulated other comprehensive income on the Partnership’s balance sheets, which will be allocated to natural gas and oil production revenue over the period of the original instruments’ contracts. As a result of the early settlement of natural gas and oil derivative positions and the unrealized gains recognized in income in prior periods due to natural gas and oil property impairments, the Partnership recorded a net deferred gain on its balance sheets in other comprehensive income of $220,700 as of March 31, 2011. Unrealized gains, net of the MGP’s interest, previously recognized into income as a result of prior period impairments were $154,500 and $187,500 for the year ended December 31, 2010 and prior periods, respectively. The MGP’s portion of the unrealized gains were written off as a result of the Transferred Business. For the three months ended March 31, 2011, the Partnership reclassified $184,200 of unrealized gains previously recognized into income from prior period impairments related to the MGP from a hedge receivable due from affiliate as a distribution to the MGP. As such $184,200 was recorded as a distribution to partners on the statement of changes in partners’ capital. During the period, $28,300 of monetized proceeds were recorded by the Partnership and allocated to the limited partners only. Of the remaining $220,700 of net unrealized gain in accumulated other comprehensive income, the Partnership will reclassify $106,700 of net gains to the Partnership’s statements of operations over the next twelve month period and the remaining $114,000 in later periods.

12

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership
NOTES TO FINANCIAL STATEMENTS (Continued)
March 31, 2011
(Unaudited)

NOTE 5 — DERIVATIVE INSTRUMENTS (Continued)

The following table summarizes the fair value of the Partnership’s derivative instruments as of December 31, 2010, as well as the gain or loss recognized in the statements of operations for the three months ended March 31, 2011 and 2010:

Fair Value of Derivative Instruments:

		Fair Value
	Balance Sheet	December 31,
Derivatives in Cash Flow Hedging Relationships	Location	2010
Derivative Commodity Contracts	Current Assets	$	380,300
	Long-Term Assets		371,400
			751,700
	Current liabilities		(1,600	)
	Long-term liabilities		(63,400	)
			(65,000	)
	Total	$	686,700

Effects of Derivative Instruments on statements of operations:

	Gain					Gain
	Recognized in OCI on Derivative					Reclassified from OCI into Loss
	(Effective Portion)				Location of Gain/Loss	(Effective Portion)
Derivatives in	Three Months Ended				Reclassified from Accumulated	Three Months Ended
Cash Flow	March 31,		March 31,		OCI into Income	March 31,		March 31,
Hedging Relationships	2011		2010		(Effective Portion)	2011		2010
Commodity Contracts	$	241,700	$	654,100	Natural Gas and Oil Revenue	$	69,100	$	34,800

NOTE 6 — FAIR VALUE OF FINANCIAL INSTRUMENTS

The Partnership has established a hierarchy to measure its financial instruments at fair value which requires it to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The hierarchy defines three levels of inputs that may be used to measure fair value:

Level 1— Quoted prices in active markets for identical assets and liabilities that the reporting entity has the ability to access at the measurement date.

Level 2— Inputs other than quoted prices included within Level 1 that are observable for the asset and liability or can be corroborated with observable market data for substantially the entire contractual term of the asset or liability.

Level 3— Unobservable inputs that reflect the entities own assumptions about the assumptions that market participants would use in the pricing of the asset or liability and are consequently not based on market activity, but rather through particular valuation techniques.

Assets and Liabilities Measured at Fair Value on a Recurring Basis

The Partnership used a fair value methodology to value the assets and liabilities for its outstanding derivative contracts (see Note 5). The Partnership’s commodity derivative contracts were valued based on observable market data related to the change in price of the underlying commodity and are therefore defined as Level 2 fair value measurements.

13

ATLAS AMERICA PUBLIC #12-2003 Limited Partnership
NOTES TO FINANCIAL STATEMENTS (Continued)
March 31, 2011
(Unaudited)

NOTE 6 — FAIR VALUE OF FINANCIAL INSTRUMENTS (Continued)

Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis

The Partnership estimates the fair value of asset retirement obligations using Level 3 inputs based on discounted cash flow projections using numerous estimates, assumptions and judgments regarding such factors at the date of establishment of an asset retirement obligation such as: amounts and timing of settlements; the credit-adjusted risk-free rate of the Partnership; and estimated inflation rates (see Note 3).

NOTE 7 — TRANSACTIONS WITH ATLAS RESOURCES, LLC AND ITS AFFILIATES

The Partnership has entered into the following significant transactions with its MGP and its affiliates as provided under its Partnership Agreement:

• Administrative costs which are included in general and administrative expenses in the Partnership’s statements of operations are payable at $75 per well per month. Administrative costs incurred for both the three months ended March 31, 2011 and 2010 were $40,700 and $43,500, respectively.

• Monthly well supervision fees which are included in production expenses in the Partnership’s statements of operations are payable at $313 per well per month, respectively, for operating and maintaining the wells. Well supervision fees incurred for the three months ended March 31, 2011 and 2010 were $170,100 and $181,600, respectively.

• Transportation fees which are included in production expenses in the Partnership’s statements of operations are generally payable at 13% of the natural gas sales price. Transportation fees incurred for the three months ended March 31, 2011 and 2010 were $49,700 and $74,600, respectively.

The MGP and its affiliates perform all administrative and management functions for the Partnership including billing revenues and paying expenses. Accounts receivable-affiliate on the Partnership’s balance sheets represents the net production revenues due from the MGP.

Subordination by Managing General Partner

Under the terms of the Partnership Agreement, the MGP may be required to subordinate up to 50% of its share of net production revenues of the Partnership to provide a distribution to the limited partners equal to at least 10% of their agreed subscriptions. Subordination is determined on a cumulative basis, in each of the first five years of Partnership operations, commencing with the first distribution of net revenues to the limited partners (June 2004). Since the inception of the Partnership, the MGP has not been required to subordinate any of its revenues to its limited partners.

14

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (UNAUDITED)

Forward-Looking Statements

When used in this Form 10-Q, the words “believes,” “anticipates,” “expects” and similar expressions are intended to identify forward-looking statements. These risks and uncertainties could cause actual results to differ materially from the results stated or implied in this document. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. We undertake no obligation to publicly release the results of any revisions to forward-looking statements which we may make to reflect events or circumstances after the date of this Form 10-Q or to reflect the occurrence of unanticipated events.

Management’s Discussion and Analysis should be read in conjunction with our Financial Statements and the Notes to our Financial Statements.

General

We are a Delaware limited partnership, formed on July 15, 2003 with Atlas Resources, LLC serving as our Managing General Partner and operator (“Atlas Resources” or “MGP”). Atlas Resources is an indirect subsidiary of Atlas Energy, L.P., formerly Atlas Pipeline Holdings, L.P. (“Atlas Energy”) (NYSE: ATLS). On February 17, 2011, Atlas Energy, a then-majority owned subsidiary of Atlas Energy, Inc. and parent of the general partner of Atlas Pipeline Partners, L.P. (“APL”) (NYSE: APL), completed an acquisition of assets from Atlas Energy, Inc., which included its investment partnership business; its oil and gas exploration, development and production activities conducted in Tennessee, Indiana, and Colorado, certain shallow wells and leases in New York and Ohio, and certain well interests in Pennsylvania and Michigan; and its ownership and management of investments in Lightfoot Capital Partners, L.P. and related entities.

Atlas Resources’ focus is on the development and/or production of natural gas and oil in the Appalachian, Michigan, Illinois, and/or Colorado basin regions of the United States of America. Atlas Resources is also a leading sponsor of and manages tax-advantaged direct investment partnerships, in which it co-invests to finance the exploitation and development of its acreage. Atlas Energy Resource Services, Inc. provides Atlas Resources with the personnel necessary to manage its assets and raise capital.

We have drilled and currently operate wells located in Pennsylvania. We have no employees and rely on our MGP for management, which in turn, relies on its parent company, Atlas Energy Holdings Operating Company, LLC for administrative services.

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Results of Operations

The following table sets forth information relating to our production revenues, volumes, sales prices, production costs and depletion during the periods indicated:

	Three Months Ended
	March 31,
	2011			2010
Production revenues (in thousands):
Gas	$	336		$	543
Oil		18			—
Total	$	354		$	543
Production volumes:
Gas (mcf/day) (1)		799			1,114
Oil (bbls/day) (1)		2			—
Total (mcfe/day) (1)		811			1,114
Average sales prices: (2)
Gas (per mcf) (1) (3)	$	6.24		$	6.61
Oil (per bbl) (1) (4)	$	88.27		$	—
Average production costs:
As a percent of revenues		77	%		59	%
Per mcfe (1)	$	3.73		$	3.20
Depletion per mcfe	$	1.52		$	2.27

(1)	“Mcf” represents thousand cubic feet, “mcfe” represents thousand cubic feet equivalent, and “bbls” represents barrels. Bbls are converted to mcfe using the ratio of six mcfs to one bbl.
(2)	Average sales prices represent accrual basis pricing after reversing the effect of previously recognized gains resulting from prior period impairment charges.
(3)	Average gas prices are calculated by including in total revenue derivative gains and losses previously recognized into income and dividing by the total volume for the period. Previously recognized derivative gains of $112,400 and $119,400 was recognized for the three months ended March 31, 2011 and 2010, respectively. The derivative gains and losses are included in other comprehensive income and resulted from prior period impairment charges.
(4)	Average oil prices are calculated by including in total revenue derivative gains previously recognized into income and dividing by the total volume for the period. There was no previously recognized derivative gain for the three months ended March 31, 2011. Previously recognized derivative gain of $200 was recognized for the three months ended March 31, 2010. The derivative gains are included in other comprehensive income and resulted from prior period impairment charges.

Natural Gas Revenues. Our natural gas revenues were $336,300 and $543,300 for the three months ended March 31, 2011 and 2010, respectively, a decrease of $207,000 (38%). The $207,000 decrease in natural gas revenues for the three months ended March 31, 2011 as compared to the prior year period was attributable to a $153,800 decrease in production volumes and a $53,200 decrease in our natural gas sales prices after the effect of financial hedges, which were driven by market conditions. Our production volumes decreased to 799 mcf per day for the three months ended March 31, 2011 from 1,114 mcf per day for the three months ended March 31, 2010, a decrease of 315 mcf per day (28%). The overall decrease in natural gas production volumes for the three months ended March 31, 2011 resulted primarily from the normal decline inherit in the life of the well.

Oil Revenues. We drill wells primarily to produce natural gas, rather than oil, but some wells have limited oil production. Our oil revenues were $17,600 and negligible for the three months ended March 31, 2011 and 2010, respectively. Our production volumes were 2 bbls per day for the three months ended March 31, 2011.

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Costs and Expenses. Production expenses were $272,700 and $321,200 for the three months ended March 31, 2011 and 2010, respectively, a decrease of $48,500 (15%). The decrease for the three months ended March 31, 2011 was primarily attributable to a decrease in transportation fees, which are affected by a decrease in production volumes, and other third party costs.

Depletion of oil and gas properties as a percentage of oil and gas revenues were 31% and 42% for the three months ended March 31, 2011 and 2010, respectively. These percentage changes are directly attributable to changes in revenues, oil and gas reserve quantities, product prices, production volumes and changes in the depletable cost basis of our oil and gas properties.

General and administrative expenses for the three months ended March 31, 2011 and 2010, were $58,300 and $56,500, respectively, an increase of $1,800 (3%). These expenses include third-party costs for services as well as the monthly administrative fees charged by our MGP, and vary from year to year due to the timing and billing of the costs and services provided to us.

Liquidity and Capital Resources

Cash provided by operating activities decreased $63,000 in the three months ended March 31, 2011 to $211,100 as compared to $274,100 for the three months ended March 31, 2010. This decrease was due to a decrease in net income before depletion and accretion of $142,700 and the decrease of a net non-cash loss on derivative values of $7,200. In addition, the change in accrued liabilities increased operating cash flows by $7,200 and an increase in the change in accounts receivable-affiliate of $79,700 for the three months ended March 31, 2011 compared to the three months ended March 31, 2010.

Cash used in financing activities decreased $31,400 during the three months ended March 31, 2011 to $232,500 from $263,900 for the three months ended March 31, 2010. This decrease was due to a decrease in cash distributions to partners.

Our MGP may withhold funds for future plugging and abandonment costs. Any additional funds, if required, will be obtained from production revenues or borrowings from our MGP or its affiliates, which are not contractually committed to make loans to us. The amount that we may borrow may not at any time exceed 5% of our total subscriptions, and we will not borrow from third-parties.

We believe that our future cash flows from operations and amounts available from borrowings from our MGP or its affiliates, if any, will be adequate to fund our operations.

Critical Accounting Policies

The discussion and analysis of our financial condition and results of operations are based upon our financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States of America. On an on-going basis, we evaluate our estimates, including those related to our asset retirement obligations, depletion and certain accrued receivables and liabilities. We base our estimates on historical experience and on various other assumptions that we believe reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. A discussion of our significant accounting policies we have adopted and followed in the preparation of our financial statements is included within “Notes to Financial Statements” in Part I, Item 1, “Financial Statements” in this quarterly report and in our Annual Report on Form 10-K for the year ended December 31, 2010.

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Subordination by Managing General Partner

Under the terms of the Partnership Agreement, the MGP may be required to subordinate up to 50% of its share of net production revenues of the Partnership to provide a distribution to the limited partners equal to at least 10% of their agreed subscriptions. Subordination is determined on a cumulative basis, in each of the first five years of Partnership operations, commencing with the first distribution of net revenues to the limited partners (June 2004). Since the inception of the Partnership, the MGP has not been required to subordinate any of its revenues to its limited partners.

ITEM 4. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed in our Securities Exchange Act of 1934 reports is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms, and that such information is accumulated and communicated to our management, including our Chairman of the Board of Directors, Chief Executive Officer, President and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure. In designing and evaluating the disclosure controls and procedures, our management recognized that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives and our management necessarily was required to apply its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

Under the supervision of our Chairman of the Board of Directors, Chief Executive Officer, President, and Chief Financial Officer, we have carried out an evaluation of the effectiveness of our disclosure controls and procedures as of the end of the period covered by this report. Based upon that evaluation, our Chairman of the Board of Directors, Chief Executive Officer, President and Chief Financial Officer, concluded that, at March 31, 2011, our disclosure controls and procedures were effective at the reasonable assurance level.

Changes in Internal Control over Financial Reporting

There have been no changes in the Partnership’s internal control over financial reporting during our most recent fiscal quarter that have materially affected, or are reasonably likely to materially effect, our internal control over financial reporting.

PART II. OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

The Managing General Partner is not aware of any legal proceedings filed against the Partnership.

Affiliates of the MGP and their subsidiaries are party to various routine legal proceedings arising in the ordinary course of their collective business. The MGP management believes that none of these actions, individually or in the aggregate, will have a material adverse effect on the MGP’s financial condition or results of operations.

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ITEM 6. EXHIBITS

EXHIBIT INDEX

Exhibit No.		Description
	4.0	Amended and Restated Certificate and Agreement of Limited Partnership for Public #12-2003 Limited Partnership (1)
	10.1	Drilling and Operating Agreement for Atlas America Public #12-2003 Limited Partnership (1)
	31.1	Certification Pursuant to Rule 13a-14/15(d)-14
	31.2	Certification Pursuant to Rule 13a-14/15(d)-14
	32.1	Certification Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
	32.2	Certification Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

(1) Filed on September 3, 2003 in the Form S-1 Registration Statement dated September 3, 2003, File No. 333-105811

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SIGNATURES

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

Atlas America Public #12-2003 Limited Partnership

	Atlas Resources, LLC, Managing General Partner
Date: May 13, 2011	By:	/s/ Freddie M. Kotek
		Freddie M. Kotek, Chairman of the Board of Directors, Chief Executive Officer and President

In accordance with the Exchange Act, this report has been signed by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

Date: May 13, 2011	By:	/s/ Jeffrey C. Simmons
		Jeffrey C. Simmons, Executive Vice President, Operations
Date: May 13, 2011	By:	/s/ Sean P. McGrath
		Sean P. McGrath, Chief Financial Officer

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EX-31.1

EXHIBIT 31.1

CERTIFICATION

I, Freddie M. Kotek, certify that:

1. I have reviewed this quarterly report on Form 10-Q for the quarter ended March 31, 2011 of Atlas America Public #12-2003 Limited Partnership;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have;

a) designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant is made known to us by others within the entity, particularly during the period in which this report is being prepared;

b) designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c) evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d) disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a) all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b) any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

By:	/s/ Freddie M. Kotek Name: Freddie M. Kotek
	Title:   Chief Executive Officer of the Managing General Partner

Date: May 13, 2011

EX-31.2

EXHIBIT 31.2

CERTIFICATION

I, Sean P. McGrath, certify that:

1. I have reviewed this quarterly report on Form 10-Q for the quarter ended March 31, 2011 of Atlas America Public #12-2003 Limited Partnership;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and for the registrant and have;

a) designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant is made known to us by others within the entity, particularly during the period in which this report is being prepared;

b) designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c) evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d) disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a) all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b) any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

By:	/s/ Sean P. McGrath Name: Sean P. McGrath
	Title:   Chief Financial Officer of the Managing General Partner

Date: May 13, 2011

EX-32.1

EXHIBIT 32.1

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Atlas America Public #12-2003 Limited Partnership (the “Partnership”) on Form 10-Q for the period ended March 31, 2011 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Freddie M. Kotek, Chief Executive Officer of the Managing General Partner, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1) the Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934, and

(2) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Partnership.

By:	/s/ Freddie M. Kotek Name: Freddie M. Kotek
	Title:   Chief Executive Officer of the Managing General Partner

Date: May 13, 2011

EX-32.2

EXHIBIT 32.2

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Atlas America Public #12-2003 Limited Partnership (the “Partnership”) on Form 10-Q for the period ended March 31, 2011 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Sean P. McGrath, Chief Financial Officer of the Partnership, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1) the Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934, and

(2) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Partnership.

By:	/s/ Sean P. McGrath Name: Sean P. McGrath
	Title:   Chief Financial Officer of the Managing General Partner

Date: May 13, 2011