Exhibit 10.16


                              AMENDED AND RESTATED
                           PATENT ASSIGNMENT AGREEMENT


     This Amended and Restated Patent Assignment Agreement is made as of
September 30, 2003, but effective as of July 7, 1998 (the "Effective Date")
between STANLEY ABRAMS ("Stan"), and BRETT ABRAMS ("Brett"), each of whose
principal address is 4871 North Mesa Drive, Castle Rock, Colorado 80104 and
NATHANIEL ENERGY CORPORATION, a Delaware corporation (the "Company"), with its
principal offices at 8001 South Interport Boulevard, Englewood, Colorado 80112.
Stan and Brett are collectively referred to as "Abrams".

     WHEREAS, Stan, Brett and the Company entered into an Agreement dated July
7, 1998 pursuant to which Abrams assigned to the Company certain patents
relating to the thermal combustor.

     WHEREAS, Stan, Brett and the Company desire to amend and restate the
agreement effective as of the Effective Date upon the terms and conditions set
forth herein.

     NOW, THEREFORE, in consideration of the respective agreements and covenants
of the parties set forth herein and for good, valuable and sufficient
consideration, the receipt and sufficiency of which is hereby acknowledged, the
parties hereto agree as follows:

     1. Assignment of Patents.

     (a) Abrams hereby grants, assigns and conveys to the Company all of
Abrams's rights, title and interests in and to all types of exclusionary or
protective rights granted (or applications therefor) for inventions (including,
without limitation, letters patent, utility models, inventor's certificates and
the like), and all reissues and extensions thereof and all renewals, divisions,
continuations and continuations-in-part thereof, recognized under federal law
and all comparable rights recognized in foreign jurisdictions or conventions or
by treaty, including, without limitation, all such rights listed on Schedule A
attached hereto relating to the thermal combuster (collectively, the "Patents").
Schedule A indicates in each case whether the applicable Patent is issued or the
subject of a pending application in the U.S. Patent & Trademark Office and any
foreign jurisdictions.

     (b) Abrams agrees to take all necessary steps to effectuate the assignment
of Patents in the U.S. Patent & Trademark Office and any foreign jurisdictions.



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     2. Reassignment of Patents. In the event (a) neither Stan nor Brett are
employed by the Company as a senior executive and a director, except as a result
of termination for cause, voluntary resignation, death or legal incompetence, or
(b) the Company ceases business operations or (c) an order of relief under the
federal bankruptcy laws is entered against the Company, then, in any such event,
Stan may, and in the event Stan is deceased or legally incompetent, Brett may,
demand in writing, that the Company immediately reassign the Patents to both or
one of the Abramses, as directed by the Abrams making such demand, and the
Company agrees to take all necessary steps to effectuate the reassignment of the
Patents in the U.S. Patent & Trademark Office and any foreign jurisdictions.

     3. Stan and Brett Representations and Warranties. Stan and Brett, jointly
and severally, hereby represent and warrant to the Company as follows, and
acknowledge that the Company is relying on such representations and warranties
in entering into and performing its agreements hereunder.

     (a) He has full power to execute and deliver this Agreement and to perform
his duties and responsibilities contemplated hereby.

     (b) Neither the execution of this Agreement nor performance hereunder will
(i) violate, conflict with or result in a breach of any provisions of, or
constitute a default (or an event which, with notice or lapse of time or both,
would constitute a default) under the terms, conditions or provisions of any
contract, agreement or other instrument or obligation to which he is a party, or
by which he may be bound, or (ii) violate any order, judgment, writ, injunction
or decree applicable to him.

     (c) As of the Effective Date, Abrams is the sole, true and lawful of the
Patents, free and clear of any lien, security agreement or other encumberance of
any kind.

     4. Company Representations and Warranties. The Company hereby represents
and warrants to Abrams as follows, and acknowledges that Abrams is relying on
such representations and warranties in entering into and performing its
agreements hereunder.

     (a) It is a corporation duly organized validly existing and in good
standing under the laws of the state of its incorporation and it has qualified
to do business as a foreign corporation in the jurisdictions, if any, outside of
such state, in which it does business and is required to so qualify.

     (b) It has full corporate power and authority to execute and deliver this
Agreement and to perform the duties and responsibilities contemplated hereby.

     (c) The execution, delivery and performance of this Agreement has been duly
authorized by its Board of Directors, as required, and no other approval are
necessary.

     (d) Neither the execution of this Agreement nor performance hereunder will
(i) violate, conflict with or result in a breach of any provisions of, or
constitute a default (or an event which, with notice or lapse of time or both,
would constitute a default) under the terms, conditions or provisions of its
Certificate of Incorporation or By-laws or any contract, agreement or other
instrument or obligation to which it is a party, or by which it may be bound, or
(ii) violate any order, judgment, writ, injunction or decree applicable to it.


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     5. Entire Agreement. This Agreement constitutes the entire agreement of the
parties with respect to the subject matter hereof. The representations,
warranties, covenants and agreements set forth in this Agreement constitute all
the representations, warranties, covenants and agreements of the parties and
upon which the parties have relied, shall not be deemed waived or otherwise
affected by any investigation made by any party hereto and, except as may be
specifically provided herein, no change, modification, amendment, addition or
termination of this Agreement or any part thereof shall be valid unless in
writing and signed by or on behalf of the party to be charged therewith.

     6. Notices. Any and all notices or other communications or deliveries
required or permitted to be given or made pursuant to any of the provisions of
this Agreement shall be deemed to have been duly given or made for all purposes
when in writing and hand delivered or sent by certified or registered mail,
return receipt requested and postage prepaid, overnight mail, nationally
recognized overnight courier or telecopier to the parties at their respective
addresses set forth above or at such other address as any party may specify by
notice given to the other party in accordance with this Section 6.

     7. Choice of Law; Severability. This Agreement shall be governed by, and
interpreted and construed in accordance with, the laws of the State of Colorado,
excluding choice of law principles thereof. In the event any clause, section or
part of this Agreement shall be held or declared to be void, illegal or invalid
for any reason, all other clauses, sections or parts of this Agreement which can
be effected without such void, illegal or invalid clause, section or part shall
nevertheless continue in full force and effect.

     8. Successors and Assigns; Assignment. This Agreement shall be binding upon
and inure to the benefit of the parties and their respective successors and
assigns; provided, however, that neither party may assign any of its rights or
delegate any of its duties under this Agreement without the prior written
consent of the other party, and further provided hereunder that with respect to
Abrams, this Agreement shall only inure to the benefit of Stan and Brett.

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

     10. Facsimile Signatures. Signatures hereon which are transmitted via
facsimile shall be deemed original signatures.


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         11. Headings; Gender. The headings, captions and/or use of a particular
gender under sections of this Agreement are for convenience and reference only
and do not in any way modify, interpret or construe the intent of the parties or
affect any of the provisions of this Agreement.



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<PAGE>


     IN WITNESS WHEREOF, the parties have executed, or have caused this
Agreement to be duly executed as of the date first above written.

                                   NATHANIEL ENERGY CORPORATION

                                   By: /s/  George A. Cretecos
                                       -----------------------------------------
                                          (Signature)

                                       George A. Cretecos
                                       -----------------------------------------
                                          (Name and Title)

                                       /s/  Stanley Abrams
                                       -----------------------------------------
                                       STANLEY ABRAMS

                                       /s/  Brett Abrams
                                       -----------------------------------------
                                       BRETT ABRAMS



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