Form of assignment of leases to the Partnership

This Assignment made this 7th day of September from PETROLEUM DEVELOPMENT CORPORATION, a Nevada Corporation, (herein called "Assignor") to PDC 2004C, Limited Partnership, (herein called "Assignee");

WITNESSETH

Assignor, for the sum of One Dollar ($1.00) and other valuable consideration, the receipt of which is hereby acknowledged, does by these presents GRANT, BARGAIN, SELL, EXCHANGE, CONVEY, ASSIGN, TRANSFER, SET OVER and DELIVER unto Assignee all of the following:

1.  The specific undivided interest shown in Exhibit A in respect of each of the oil and gas leases shown in Exhibit A, but only to the extent such leases cover lands and depths necessary for production of the specific oil and gas well identified in Exhibit A, This is intended to be a "wellbore assignment." Assignee shall be entitled to receive that share of production from the well identified in Exhibit A which is attributable to the undivided interest here being assigned, but the Assignee shall have, as a result of this Assignment, no interest whatsoever in any other oil and gas well, whether now existing or hereafter drilled, which may be located on the lands described in Exhibit A or on any land pooled therewith. Assignor expressly excepts from this Assignment and reserves to itself, Its successors and assigns, the remainder of the lease and the leasehold oil and gas estate, including (without limitation) the right to produce other wells which are or may be located on the lands described in Exhibit A and lands pooled therewith, without the obligation to account to Assignee for any such other production.

2.  The specific undivided interest shown in Exhibit A in all valid unitization, pooling, operating and communitization agreements, declarations and orders involving the leasehold interests here being assigned, but only to the extent that such agreements, declarations and orders relate to the well specifically identified In Exhibit A and in all other respects limited to the manner as set forth in Paragraph 1, above.

3.  The specific undivided interest shown in Exhibit A In all valid oil and gas sales, purchase, exchange and processing contracts, but only to the extent that such contracts relate to the well specifically identified in Exhibit A and in all other respects limited in the manner set forth in Paragraph 1, above.

4.  The specific undivided interest shown in Exhibit A in all personal property, improvements, lease and well equipment, easements, permits, licenses, servitudes and rights-of-way now owned by Assignor and being used in connection with the operation of the well specifically identified in Exhibit A or in connection with the production, treating, storing, transportation or marketing of oil, gas and other minerals from that well, but In all respects limited in the manner set forth in Paragraph 1, above.

TO HAVE AND TO HOLD the interests described unto Assignee, its successors and assigns, forever.

This Assignment is made without warranties of any type (whether of title, merchantability or fitness for a particular use), either express or Implied, but is made with full substitution of Assignee in all covenants and warranties previously given or made by others, but only to the extent of the interests here assigned. Assignor does, however, expressly intend that this Assignment convey any title that Assignor may hereafter acquire to the extent that such after-acquired title may be necessary to fulfill the interests herein assigned.

Assignee shall bear its proportionate share of all burdens on production now of record and hereby assumes its proportionate share of all other obligations that relate to the well specifically identified in Exhibit A and the production therefrom.

IN WITNESS WHEREOF, Petroleum Development Corporation has executed and delivered this instrument, with the intention that it shall be effective as of the date of first production from the well specifically identified in Exhibit A.

The foregoing instrument was acknowledged before me this 16th day of September 2004 by William D. Gainor, Land Manager of Petroleum Development Corporation, a Nevada Corporation, for and on behalf of the Corporation. He executed the foregoing for the purposes therein contained.

OFFICIAL SEAL		/s/ Rita A. Clark
Note Public. State of West Virginia		Rita A. Clark
RITA A. CLARK		Notary Public -	State of West Virginia
Petroleum Development Corporation			County of Harrison
103 East Main Street. Box 26		My commission expires: June 2, 2009
Bridgeport, WV 26330
My commission expires June 2, 2009

This Instrument was prepared by:

Petroleum Development Corporation

103 East Main Street

P. O. Box 26

Bridgeport, WV 26330

Ph: 1 ###-###-#### or ###-###-####

AMENDMENT TO

ASSIGNMENT OF WORKING INTEREST

THIS AMENDMENT TO ASSIGNMENT OF WORKING INTEREST is made March 8, 2006 between Petroleum Development Corporation, a Nevada corporation, and PDC 2004-C Limited Partnership, a West Virginia limited partnership whose address is P. O. Box 26, Bridgeport, West Virginia 26330.

1.    Background. By this instrument, the parties correct and amend the Assignment of Working Interest (the "Original Assignment"), dated September 7, 2004 and recorded as Instrument No, 3282449 in the real property records of Weld County, Colorado.

2.     Amendment. Petroleum Development Corporation and PDC 2004-C Limited Partnership hereby amend the Original Assignment by deleting in its entirety the Exhibit A that is attached to the Original. Assignment and replacing it with the Exhibit A that is attached to this instrument. All other provisions of the Original Assignment are unchanged.

3.     Effective Date. The parties intend that this amendment be deemed effective at the effective date of the Original Assignment, just as if the Exhibit A that is attached to this instrument had originally been attached to the Original Assignment.

IN WITNESS WHEREOF, this instrument has been executed by the parties.

The foregoing instrument was acknowledged before me this 5th day of April, 2006, by Ersel E. Morgan, as Vice President of Petroleum Development Corporation, the Managing General Partner of PDC 2004-C Limited Partnership, a West Virginia limited partnership.

Witness my hand and official seal.