Exhibit 10.59

RETENTION AGREEMENT

THIS RETENTION AGREEMENT (the “Agreement”), is made effective the      day of
December, 2006 (the “Effective Date”), by and between Syntroleum Corporation
(the “Company”), and [Name] (the “Employee”).

WHEREAS, it is the Company’s belief that the Employee’s continued employment
with the Company is important for the growth and development of the Company;

NOW, THEREFORE, in consideration of the mutual promises and agreements contained
herein, and other good and valuable consideration, the adequacy of which is
hereby acknowledged, the parties hereby agree as follows:

1. Definitions: Exhibit A contains a list of defined terms as used in this
Agreement.

2. Cash Retention Benefit:

 

  (a) If:

 

  (i) the Employee remains employed through the end of the First Retention
Period,

 

  (ii) the Employee’s employment is terminated by the Company Without Cause or
by the Employee for Good Reason prior to the end of the First Retention Period,
or

 

  (iii) the Employee terminates employment during the First Retention Period due
to his death or Disability,

then the Employee shall be entitled to a Retention Payment equal to
$             (the “First Retention Payment”).

(b) If Employee becomes entitled to receive the First Retention Payment, such
First Retention Payment will be paid within 10 business days following the
earlier of his termination of employment from the Company or the expiration of
the Retention Period.

(c) If Employee voluntarily terminates his employment prior to the First
Retention Payment having paid pursuant to the provisions of Section 2(a), the
Employee shall forfeit all right to the First Retention Payment.

3. Second Retention Payment:

 

  (a) If:

 

  (i) the Employee remains employed through the end of the Second Retention
Period,

 

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  (ii) the Employee’s employment is terminated by the Company Without Cause or
by the Employee for Good Reason prior to the end of the Second Retention Period,
or

 

  (iii) the Employee terminates employment during the Second Retention Period
due to his death or Disability,

then the Employee shall be entitled to a Second Retention Payment equal to 50%
of the Employee’s annual base salary as of June 29, 2007 or the date of his
termination of employment, whichever is earlier.

(b) If Employee becomes entitled to receive the Second Retention Payment, such
Second Retention Payment will be paid as provided in Section 3(c) below within
10 business days following the earlier of his termination of employment from the
Company or the expiration of the Second Retention Period

(c) The Company will have an election to make the Second Retention Payment in
cash, a Stock grant pursuant to the Syntroleum Corporation 2005 Stock Incentive
Plan (“the Plan”), or a combination thereof, subject to the conditions and
restrictions set forth below and in the Plan.

(d) If Employee voluntarily terminates his employment prior to the Second
Retention Payment having been paid, granted or vested pursuant to the provisions
of Section 3(c), the Employee shall forfeit all right to the Second Retention
Payment which has not yet been paid, granted or vested as of the date of
termination of employment.

(e) The Employee shall have no rights as a stockholder of the Company with
respect to any shares of Stock which may be granted hereunder until such shares
are issued pursuant to clause (c) above. .

4. Withholding of Taxes: The Company may withhold from any benefits payable
under this agreement all federal, state, city or other taxes as may be required
pursuant to any law or governmental regulation or ruling.

5. No Employment Agreement: Nothing in this agreement shall give the Employee
any rights to (or impose any obligations for) continued employment by the
Company or any Affiliate or subsidiary thereof or successor thereto, nor shall
it give such entities any rights (or impose any obligations) with respect to
continued performance of duties by the Employee. Any payments due under this
Agreement shall be in addition to, and not in lieu of, any payments that may be
due under any Employment Agreement between the Company and the Employee.

6. Effect of Leaves of Absence: Authorized leaves of absence from the Company
shall not constitute a termination of employment for purposes of this Agreement.
For purposes of this Agreement, an authorized leave of absence shall be an
absence while Employee is on military leave, sick leave, or other bona fide
leave of absence so long as Employee’s right to employment with the Company is
guaranteed by statute, contract, or company policy.

 

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7. No Assignment; Successors: Employee’s right to receive payments or benefits
hereunder shall not be assignable or transferable, whether by pledge, creation
of a security interest or otherwise, whether voluntary, involuntary, by
operation of law or otherwise, other than a transfer by will or by the laws of
descent or distribution, and in the event of any attempted assignment or
transfer contrary to this Section 7 the Company shall have no liability to pay
any amount so attempted to be assigned or transferred. This agreement shall
inure to the benefit of and be enforceable by Employee’s personal or legal
representatives, executors, administrators, successors, heirs, distributees,
devisees and legatees.

This agreement shall be binding upon and inure to the benefit of the Company,
its successors and assigns, including, without limitation, any company into or
with which the Company may merge or consolidate by operation of law or
otherwise.

8. Entire Agreement: This agreement represents the entire agreement between the
Company and Employee with respect to the subject matter hereof, and supersedes
and is in full substitution for any and all prior agreements or understandings,
whether oral or written, relating to the subject matter hereof.

9. Modification of Agreement. Any modification of this agreement shall be
binding only if evidenced in writing and signed by an authorized representative
of the Company.

10. Applicable Law: This agreement is entered into under, and shall be governed
for all purposes by, the laws of the State of Oklahoma.

11. Severability: If a court of competent jurisdiction determines that any
provision of this agreement is invalid or unenforceable, then the invalidity or
unenforceability of that provision shall not affect the validity or
enforceability of any other provision of this agreement and all other provisions
shall remain in full force and effect.

IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.

 

SYNTROLEUM CORPORATION

By  

 

  [Name]   [Title] EMPLOYEE

 

[Name]

 

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Exhibit A

Definitions

For purposes of this Agreement, the following terms will have the meanings
indicated below:

“Cause” shall mean termination of employment by the Company or an Affiliate due
to any of the following: (A) Employee’s material breach of his obligations,
duties and responsibilities under any term or provision of this Agreement, which
breach remains uncured for a period of five days after written notice by the
Company to Employee; (B) Employee’s failure to adhere to the reasonable
standards of performance prescribed by the Company; (C) Employee’s act of
insubordination to the Company’s Board of Directors; (D) Employee’s gross
negligence or willful misconduct in the performance of his duties under this
Agreement; (E) Employee’s dishonesty, fraud, misappropriation or embezzlement in
the course of, related to or connected with the business of the Company;
(F) Employee’s conviction of a felony; or (G) Employee’s failure (after written
notice to Employee of such failure and Employee not correcting such failure
within five days of such notice) to devote his time, attention and best efforts
to the business of the Company as provided in this Agreement. The determination
of “just cause” under subsections (A) through (G) shall be made at the sole
discretion and decision the Company.

“Disability” means “Disability” as defined in the Employment Agreement between
the Company and the Employee.

“First Retention Period” shall mean the period commencing on the Effective Date
and ending on June 29, 2007.

“Good Reason” shall mean

(a) any material failure by the Company to comply with any of the provisions of
the Employment Agreement between the Employee and the Company, other than an
isolated, insubstantial and inadvertent failure not occurring in bad faith and
which is remedied by the Company promptly after receipt of notice thereof given
by the Employee; or

(b) the Company’s requiring the Employee to be based at any office outside the
Tulsa metropolitan area.

“Second Retention Period” shall mean the period commencing on the Effective Date
and ending on July 1, 2008.

“Without Cause” shall mean without Cause and for reasons other than death or
Disability of the Employee.

 

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