Exhibit 10.3

VOTING AGREEMENT

THIS VOTING AGREEMENT (this “Agreement”) dated as of June 29, 2007 is by and
among Atlas America, Inc., a Delaware corporation (“Atlas America”), and Atlas
Energy Management, Inc., a Delaware corporation (“Atlas Management”).

WHEREAS, reference is made to the Class D Unit and Common Unit Purchase
Agreement (the “Purchase Agreement”) relating to the proposed private placement
to certain institutional investors of Class D Units and Common Units of Atlas
Energy Resources, LLC (the “Company”); and

WHEREAS, reference is made to the Purchase Agreement, whereby the Company will
agree to take all action necessary to convene a meeting of its Unitholders to
consider and vote upon, or obtain the consent of its Unitholders to, the
conversion of the Purchasers’ Class D Units into Common Units (the “Conversion”)
as soon as practicable, but in any event not later than 135 days following the
Closing Date; and

WHEREAS, each of Atlas America and Atlas Management are record holders of Units
(“Voting Units”) representing limited liability company interests in the
Company, and each of them desires to set forth certain agreements and
arrangements related to the voting of such Voting Units in respect of the
conversion of the Class D Units into Common Units.

NOW, THEREFORE, in consideration of the premises and the covenants and
agreements contained herein, and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, and intending to be
legally bound hereby, the parties hereby agree as follows:

1. Effectiveness. The provisions of this Agreement shall be effective upon the
date first written above.

2. Definitions. Capitalized terms used herein without definition shall have the
meanings given to them in the Purchase Agreement.

3. Agreement to Vote. At any meeting of the Unitholders convened to consider and
vote upon the Conversion or in connection with any solicitation of consents to
the conversion, each of Atlas America and Atlas Management unconditionally and
irrevocably agrees to vote all of the Units owned by such person on the record
date fixed by the Company’s Board of Directors for any such meeting, or to give
its consent in a consent solicitation, in favor of the conversion of the Class D
Units into Common Units.

4. Additional Covenants. As applicable, the parties shall cause their respective
officers, employees and agents to take all requisite action requested by the
Company or the Purchasers to carry out their obligations under this Agreement.

5. Specific Enforcement. It is agreed and understood that monetary damages would
not adequately compensate an injured party for the breach of this Agreement by
any party, that this Agreement shall be specifically enforceable, and that any
breach or threatened breach of this Agreement shall be the proper subject of a
temporary or permanent injunction or restraining order without a requirement of
posting bond. Further, each party hereto waives any claim or defense that there
is an adequate remedy at law for such breach or threatened breach.

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6. Representations and Warranties. Each of Atlas America and Atlas Management
hereby represents and warrants with respect to itself, on and as of the date of
this Agreement, as follows:

(a) It has full right, power and authority to vote the Voting Units, held of
record by it, in the manner contemplated herein.

(b) The Voting Units represent approximately 29,352,996 Common Units and 748,456
Class A Units.

(c) It has all requisite power and authority to enter into and perform its
obligations under this Agreement. The execution, delivery and performance of
this Agreement have been duly authorized by all necessary action on the part of
such party. This Agreement has been duly executed and delivered by such party.
This Agreement constitutes its legal, valid and binding obligation, enforceable
in accordance with its terms, except as such enforceability may be limited by
bankruptcy, insolvency, fraudulent transfer and similar laws affecting
creditors’ rights generally or by general principles of equity.

(d) The execution, delivery and performance of this Agreement will not, with or
without the giving of notice or the passage of time, (i) violate any judgment,
injunction, order or decree of any court, arbitrator or governmental agency
applicable to such party, or (ii) conflict with, result in the breach of any
provision of, constitute a default under, or require the consent or approval of
any third party under, any agreement or instrument to which such party is a
party or by which such party is bound.

7. Covenants.

(a) Until the termination of this Agreement, such party will not enter into any
transaction, take any action or by inaction permit any event to occur that would
result in any of the representations or warranties of such party herein
contained not being true and correct or that would prevent or otherwise restrict
such party from performing its obligations under this Agreement. None of the
parties to this Agreement shall be subject to any restrictions on transfer as a
result of entering into this Agreement, except that in any transfer of all or
any portion of any such party’s Voting Units such transferee shall agree in
writing to be bound by the terms of this Agreement.

(b) Such party shall execute and deliver any additional documents reasonably
necessary or desirable to evidence the agreement to vote granted herein with
respect to the Voting Units or otherwise implement and effect the provisions of
this Agreement.

8. Third Party Beneficiaries. Each of Atlas America and Atlas Management
acknowledges that the beneficiaries of the terms of this Agreement are the
Purchasers who purchase Class D Units pursuant to the Purchase Agreement. Each
of Atlas America and Atlas Management acknowledges further and agrees that such
Purchasers shall have the right to enforce this Agreement. Nothing in this
Agreement shall be construed to impose any personal liability on any officer,
employee, director, incorporator, member, manager, partner or stockholder of any
party or any of its affiliates.

9. Captions. The captions and headings used in this Agreement are for
convenience only and do not in any way limit or amplify the terms and provisions
hereof.

 

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10. Manner of Voting. The voting of the Voting Units owned by Atlas America and
Atlas Management may be effected in person, by proxy, by written consent, or in
any other manner permitted by applicable law.

11. Splits, Dividends, Etc. If there shall be any issuance of voting securities
hereafter to any of the parties hereto (including in connection with any split,
dividend, recapitalization, reorganization, or the like), such securities shall
become subject to this Agreement.

12. Amendments. This Agreement may not be modified or amended without: (i) the
written consent of the Purchasers entitled to purchase a majority of the
Purchased Units and the Purchased Class D Units based on the Common Unit Price
and the Class D Unit Purchase Price, as the case may be and (ii) an instrument
or instruments in writing signed by each of Atlas America and Atlas Management.

13. Notices. All notices or other communications under this Agreement shall be
in writing and shall be given (and shall be deemed to have been duly given upon
receipt) by delivery in person, by telecopy (with confirmation of receipt), or
by registered or certified mail, postage prepaid, return receipt requested,
addressed to the notice address specified on the applicable signature page to
this Agreement.

14. Entire Agreement. This Agreement is intended to be the sole agreement of the
parties as it relates to this subject matter.

15. Severability. If any provision of this Agreement shall be held invalid,
illegal or unenforceable, the validity, legality or enforceability of the other
provisions of this Agreement shall not be affected thereby, and there shall be
deemed substituted for the provision at issue a valid, legal and enforceable
provision as similar as possible to the provision at issue.

16. Governing Law. This Agreement shall be governed by and construed under the
laws of the State of New York, without reference to the principles of conflicts
of law.

17. Counterparts. This Agreement may be executed in counterparts, each of which
shall be deemed an original, but all of which together shall constitute one and
the same instrument.

18. No Partnership, Agency or Joint Venture. This Agreement is intended to
create, and creates, a contractual relationship and is not intended to create,
and does not create, any agency, partnership, joint venture or any like
relationship among the parties hereto.

19. Termination. This Agreement shall (i) terminate automatically following the
satisfaction by the Company of its obligations under Section 5.03 of the
Purchase Agreement and (ii) shall be deemed satisfied in full and terminated
upon the consummation of the Conversion. In the event of termination of this
Agreement pursuant to this Section 19, this Agreement shall become void and of
no effect with no liability on the part of any party hereto; provided, however,
no such termination shall relieve any party hereto from any liability for any
breach of this Agreement occurring prior to such termination.

 

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IN WITNESS WHEREOF, the parties have executed this Voting Agreement as of the
day and year hereinabove first written.

 

ATLAS AMERICA, INC. By:  

 

Name:   Matthew A. Jones Title:   Chief Financial Officer ATLAS ENERGY
MANAGEMENT, INC. By:  

 

Name:   Matthew A. Jones Title:   Chief Financial Officer

 

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