Exhibit 10.21

SemGroup Corporation

Equity Incentive Plan

RESTRICTED STOCK AWARD AGREEMENT

THIS RESTRICTED STOCK AWARD AGREEMENT (this “Agreement”) is made effective as of
                    , 2012 (the “Date of Grant”) by and between SemGroup
Corporation, a Delaware corporation (with any successor, the “Company”), and
                    (the “Participant”).

R E C I T A L S:

WHEREAS, the Company has adopted the SemGroup Corporation Equity Incentive Plan
(the “Plan”) and, pursuant to and in accordance with the Plan, has approved
SemGroup Corporation Long-Term Incentive Program (the “LTIP”) as reflected in
relevant part in this Agreement, which Plan and LTIP, as each may be amended
from time to time, are incorporated herein by reference and made a part of this
Agreement. Capitalized terms not otherwise defined herein shall have the same
meanings as ascribed to them in the Plan; and

WHEREAS, the Committee has determined that it would be in the best interests of
the Company and its stockholders to grant the Shares of Restricted Stock (the
“Restricted Shares”) provided for herein to the Participant pursuant to the Plan
and the terms set forth herein.

NOW THEREFORE, in consideration of the mutual covenants hereinafter set forth,
the parties agree as follows:

1. Restricted Stock Award. Subject to the terms and conditions of the Plan and
this Agreement, the Company hereby grants to the Participant             
Restricted Shares, which shall vest and become nonforfeitable in accordance with
Section 3 hereof.

2. Certificates; Payment.

(a) Certificates. A certificate or certificates representing the Restricted
Shares shall be issued by the Company and shall be registered in the name of the
Participant on the stock transfer books of the Company promptly following
execution of this Agreement by the Participant, but shall remain in the physical
custody of the Company or its designee at all times prior to the vesting of such
Restricted Shares pursuant to Section 3 hereof. As a condition to the receipt of
this Agreement, the Participant shall deliver to the Company a Stock Power in
the form attached hereto as Exhibit A, duly endorsed in blank, relating to the
Restricted Shares. Each certificate representing the Restricted Shares shall
bear the following legend:

The ownership and transferability of this certificate and these shares are
subject to the terms and conditions (including forfeiture) of the SemGroup
Corporation Equity Incentive Plan, the SemGroup Corporation Long-Term Incentive
Program, the SemGroup Corporation Executive Stock Ownership Policy and a
Restricted Stock Award Agreement entered into between the registered owner and
SemGroup Corporation. Copies of such Plan, Program, Policy and Agreement are on
file in the executive offices of SemGroup Corporation.

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(b) Payment. As soon as administratively practicable, but not later than sixty
(60) days, following the vesting of the Restricted Shares (as described in
Section 3 hereof), and upon the satisfaction of all other applicable conditions,
including, but not limited to, the payment by the Participant of all applicable
withholding taxes, the Company shall deliver or cause to be delivered to the
Participant, or in the case of Participant’s death, Participant’s beneficiary, a
certificate or certificates for the applicable Restricted Shares and Shares
representing Dividends paid on such Shares which shall not bear the legend
described above, but may bear such other legends as the Company deems advisable
pursuant to Section 6 below

3. Vesting of Restricted Shares.

(a) Vesting Schedule. Subject to the Participant’s continued Service through the
applicable vesting date, the Restricted Shares shall vest and become
nonforfeitable on                     , 2015. For Purposes of this Agreement,
the term “Vesting Period” means the period commencing on the Date of Grant and
continuing through                     , 2015.

(b) Change of Control. If the Participant’s Service is terminated by the Company
without Cause or by the Participant for Good Reason after or, as determined by
the Committee, in connection with, a Change of Control, all of the unvested
Restricted Shares shall vest and become nonforfeitable on the date of such
termination.

(c) Death or Disability. If the Participant dies or becomes Disabled during the
Vesting Period before the Participant’s Service otherwise terminates, the
Restricted Shares awarded hereunder will vest and become nonforfeitable upon
such death or Disability and be paid to the Participant or, in the case of
death, to the Participant’s beneficiary, at the time and in the manner set forth
in Section 2 above.

(d) Involuntary Termination of Service. If the Participant’s Service is
involuntarily terminated by the Company, as the direct result of a divestiture
or otherwise, in each case without Cause, then any unvested Restricted Shares
shall become fully vested upon such termination of Service.

(e) Other Termination of Service. If the Participant’s Service is terminated for
any reason, other than as described in Section 3(b), Section 3(c) or
Section 3(d) above, the Restricted Shares, to the extent then unvested, and
Dividends, if any, distributed thereon shall be forfeited by the Participant
without any consideration.

 

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(f) Forfeiture and Cancellation of Restricted Shares and Dividends. Any
Restricted Shares that remain unvested, and Dividends, if any, distributed on
unvested Restricted Shares, after                     , 2015, shall be forfeited
without consideration.

4. No Right to Continued Service. The granting of the Restricted Shares
evidenced hereby and this Agreement shall impose no obligation on the Company or
any Affiliate to continue the Service of the Participant and shall not lessen or
affect any right that the Company or any Affiliate may have to terminate the
Service of such Participant.

5. Rights as a Stockholder.

(a) During the Restriction Period, the Participant shall have none of the rights
of a Stockholder of the Company, except that the Participant shall: (a) be
entitled to exercise all of the voting rights of a Stockholder of the Company,
and (b) have the right to receive dividends on the Restricted Shares that vest
and become nonforfeitable under this Agreement (the “Dividends”), subject to the
remainder of this Section 5.

(b) The Dividends, if any, shall be held by the Company and shall be subject to
forfeiture until such time that the Restricted Shares on which the Dividends
were distributed vest and become nonforfeitable in accordance with Section 3
above. The Dividends that vest and become nonforfeitable in accordance with this
Section 5 shall be converted into Shares and released to the Participant,
subject to Section 10 hereof, as soon as administratively practicable following
vesting of the Restricted Shares on which such Dividends were distributed, but
not later than the time of delivery to the Participant, in accordance with
Section 2 above, of certificates representing the Restricted Shares on which the
Dividends were distributed. The number of Shares payable with respect to any
Dividends released to the Participant under this Section 5 shall equal the
dollar amount of Dividends distributed by the Company on Restricted Shares that
vest and become nonforfeitable under this Agreement divided by the Fair Market
Value of a Share at the close of business on the day such Dividends vest and
become nonforfeitable. Partial shares will be paid in cash.

(c) Until converted into Shares and released to the Participant, the Dividends
shall remain assets of the Company subject to the claims of the Company’s
general creditors. Dividends distributed and held by the Company on any
Restricted Shares that do not vest in accordance with Section 3 hereof shall be
forfeited by the Participant without any consideration.

6. Securities Laws; Legend on Certificates. The issuance and delivery of
Restricted Shares and Shares representing Dividends shall comply with all
applicable requirements of law, including (without limitation) the Securities
Act of 1933, as amended, the rules and regulations promulgated thereunder, state
securities laws and regulations, and the

 

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regulations of any stock exchange or other securities market on which the
Company’s securities may then be traded. If the Company deems it necessary to
ensure that the issuance of Restricted Shares and Shares representing Dividends
under the Plan is not required to be registered under any applicable securities
laws, each Participant to whom such Restricted Shares and Shares would be issued
shall deliver to the Company an agreement or certificate containing such
representations, warranties and covenants as the Company may request which
satisfies such requirements. The certificates representing the Restricted Shares
and Shares representing Dividends shall be subject to such stop transfer orders
and other restrictions as the Committee may deem reasonably advisable, and the
Committee may cause a legend or legends to be put on any such certificates to
make appropriate reference to such restrictions.

7. Transferability of Restricted Shares.

(a) Before Vesting. Prior to vesting, the Restricted Shares may not be assigned,
alienated, pledged, attached, sold or otherwise transferred or encumbered by the
Participant other than by will or by the laws of descent and distribution, and
any such purported assignment, alienation, pledge, attachment, sale, transfer or
encumbrance shall be void and unenforceable against the Company and all
Affiliates; provided that the designation of a beneficiary for receipt of any
Restricted Shares and/or Dividends shall not constitute an assignment,
alienation, pledge, attachment, sale, transfer or encumbrance. No such permitted
transfer of the Restricted Shares to heirs or legatees of the Participant shall
be effective to bind the Company unless the Committee shall have been furnished
with written notice thereof and a copy of such evidence as the Committee may
deem necessary to establish the validity of the transfer and the acceptance by
the transferee or transferees of the terms and conditions hereof.

(b) Before and After Vesting. In addition to other restrictions imposed
hereunder or otherwise by the Committee or by law, transferability of Restricted
Shares and Shares, if any, representing Dividends shall be subject to the
SemGroup Corporation Executive Stock Ownership Policy as approved by the
Committee.

8. Adjustment of Restricted Shares. Adjustments to the Restricted Shares shall
be made in accordance with Article 12 of the Plan.

9. Definitions. The following terms shall have the meanings set forth below:

“Cause” shall mean, with respect to the Participant, one or more of the
following: (a) the plea of guilty or nolo contendere to, or conviction of, the
commission of a felony offense (b) any act of willful fraud, dishonesty or moral
turpitude that causes a material harm to the Company or any Subsidiary or
Affiliate, (c) gross negligence or gross misconduct with respect to the Company
or any Subsidiary or Affiliate, (d) willful and deliberate failure to perform
his or her employment duties in any material respect, or (e) breach of a
material written employment policy of the Company or any Subsidiary or
Affiliate, provided, however, that in the case of a Participant who has an
employment agreement with the Company or any Subsidiary or Affiliate in which
“Cause” is defined, “Cause” shall be determined in accordance with such
definition.

 

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“Good Reason” shall mean the occurrence of one or more of the following without
the consent of the Participant: (a) a material reduction in the Participant’s
base salary or incentive compensation opportunity (other than a general
reduction that affects all similarly situated Participants equally) (b) a
material reduction of Participant’s duties and responsibilities or an adverse
change in Participant’s title, or (c) a transfer of Participant’s primary
workplace by more than thirty-five (35) miles from the location of Participant’s
current primary workplace, provided, that Participant shall first have given the
Company written notice that an event or condition constituting Good Reason has
occurred and specifying in reasonable detail the circumstances constituting such
Good Reason within thirty (30) days after such occurrence, and the Company shall
have a period of thirty (30) days after receiving such written notice to
effectively cure or remedy such occurrence, and provided, further, that, that in
the case of a Participant who has an employment agreement with the Company or
any Subsidiary or Affiliate in which “Good Reason” is defined, “Good Reason”
shall be determined in accordance with such definition.

“Disability” or “Disabled” shall have the meaning set forth in the Company’s
long-term disability plan.

10. Withholding.

(a) Participant’s Payment Obligation. The Participant agrees that (i) he or she
will pay to the Company or any applicable Subsidiary, as the case may be, or
make arrangements satisfactory to the Company or such Subsidiary regarding the
payment of any foreign, federal, state, or local taxes of any kind required by
law to be withheld by the Company or such Subsidiary with respect to the
Restricted Shares, and (ii) the Company, or such Subsidiary, shall, to the
extent permitted by law, have the right to deduct from any payments of any kind
otherwise due to the Participant any foreign, federal, state, or local taxes of
any kind required by law to be withheld with respect to the Restricted Shares.

(b) Withholding Restricted Shares and Shares Representing Dividends. With
respect to withholding required upon the lapse of restrictions or upon any other
taxable event arising as a result of the Restricted Shares awarded and/or
Dividends vesting, the Participant may elect, subject to the approval of the
Committee, to satisfy the withholding requirement, in whole or in part, by
having the Company or any applicable subsidiary withhold Restricted Shares
and/or Shares representing Dividends having a Fair Market Value on the date the
tax is to be determined equal to the minimum statutory total tax which could be
withheld on the transaction. All such elections shall be irrevocable, made in
writing, signed by the Participant, and shall be subject to any restrictions or
limitations that the Committee, in its sole discretion, deems appropriate.

11. Notices. Any notification required by the terms of this Agreement shall be
given in writing and shall be deemed effective upon personal delivery or within
three (3) days of deposit with the United States Postal Service (or in the case
of a non-U.S. Participant, the foreign postal service of the country in which
the Participant resides), by registered or certified mail, with postage and fees
prepaid. A notice shall be addressed to the Company, Attention: General Counsel,
at its principal executive office and to the Participant at the address that he
or she most recently provided to the Company.

 

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12. Entire Agreement. This Agreement and the Plan constitute the entire contract
between the parties hereto with regard to the subject matter hereof. They
supersede any other agreements, representations or understandings (whether oral
or written and whether express or implied) which relate to the subject matter
hereof.

13. Waiver. No waiver of any breach or condition of this Agreement shall be
deemed to be a waiver of any other or subsequent breach or condition whether of
like or different nature.

14. Participant Undertaking. The Participant agrees to take whatever additional
action and execute whatever additional documents the Company may deem necessary
or advisable to carry out or effect one or more of the obligations or
restrictions imposed on either the Participant or the Restricted Shares pursuant
to this Agreement.

15. Successors and Assigns. The provisions of this Agreement shall inure to the
benefit of, and be binding upon, the Company and its successors and assigns and
upon the Participant, the Participant’s assigns and the legal representatives,
heirs and legatees of the Participant’s estate, whether or not any such person
shall have become a party to this Agreement and agreed in writing to be joined
herein and be bound by the terms hereof.

16. Choice of Law; Jurisdiction; Waiver of Jury Trial. This Agreement shall be
governed by the laws of the State of Delaware, excluding any conflicts or choice
of law rule or principle that might otherwise refer construction or
interpretation of the Plan to the substantive law of another jurisdiction.

SUBJECT TO THE TERMS OF THIS AGREEMENT, THE PARTIES AGREE THAT ANY AND ALL
ACTIONS ARISING UNDER OR IN RESPECT OF THIS AGREEMENT SHALL BE LITIGATED IN THE
FEDERAL OR STATE COURTS IN DELAWARE. BY EXECUTING AND DELIVERING THIS AGREEMENT,
EACH PARTY IRREVOCABLY SUBMITS TO THE PERSONAL JURISDICTION OF SUCH COURTS FOR
ITSELF, HIMSELF OR HERSELF AND IN RESPECT OF ITS, HIS OR HER PROPERTY WITH
RESPECT TO SUCH ACTION. EACH PARTY AGREES THAT VENUE WOULD BE PROPER IN ANY OF
SUCH COURTS, AND HEREBY WAIVES ANY OBJECTION THAT ANY SUCH COURT IS AN IMPROPER
OR INCONVENIENT FORUM FOR THE RESOLUTION OF ANY SUCH ACTION.

EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY WAIVES ALL RIGHT TO TRIAL BY JURY
IN ANY ACTION, PROCEEDING OR COUNTERCLAIM ARISING OUT OF OR RELATING TO THIS
AGREEMENT.

17. Restricted Shares Subject to Plan. By entering into this Agreement the
Participant agrees and acknowledges that the Participant has received and read a
copy of the Plan. The Restricted Shares are subject to the Plan. In the event of
a conflict between any term or provision contained herein and a term or
provision of the Plan, the applicable terms and provisions of the Plan will
govern and prevail. The Participant has had the opportunity to retain counsel,
and has read carefully, and understands, the provisions of the Plan and this
Agreement.

 

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18. Amendment. The Committee may amend or alter this Agreement, the LTIP and the
Restricted Shares granted hereunder at any time; provided, that, subject to
Article 10, Article 11 and Article 12 of the Plan, no such amendment or
alteration shall be made without the consent of the Participant if such action
would materially diminish any of the rights of the Participant under this
Agreement or with respect to the Restricted Shares.

19. No Section 83(b) Election. The Participant agrees not to make an election
with the Internal Revenue Service under Section 83(b) of the Code with respect
to the Restricted Shares.

20. Severability. The provisions of this Agreement are severable and if any one
or more provisions are determined to be illegal or otherwise unenforceable, in
whole or in part, the remaining provisions shall nevertheless be binding and
enforceable.

21. Signature in Counterparts. This Agreement may be signed in counterparts,
each of which shall be an original, with the same effect as if the signatures
thereto and hereto were upon the same instrument.

22. No Guarantees Regarding Tax Treatment. Participants (or their beneficiaries)
shall be responsible for all taxes with respect to the Restricted Shares and the
Dividends. The Committee and the Company make no guarantees regarding the tax
treatment of the Restricted Shares or the Dividends. Neither the Committee nor
the Company has any obligation to take any action to prevent the assessment of
any tax under Section 409A of the Code or Section 457A of the Code or otherwise
and none of the Company, any Subsidiary or Affiliate, or any of their employees
or representatives shall have any liability to a Participant with respect
thereto.

23. Compliance with Section 409A. The Company intends that the Restricted Shares
and right to receive Dividends be structured in compliance with, or to satisfy
an exemption from, Section 409A of the Code and all regulations, guidance,
compliance programs and other interpretative authority thereunder (“Section
409A”), such that there are no adverse tax consequences, interest, or penalties
under Section 409A as a result of the award, vesting or payment of the
Restricted Shares or payment of Dividends. Accordingly, in the event of any
ambiguity, the Agreement shall be construed and administered in accordance with
such intent. In addition, in the event the Restricted Shares or Dividends are
subject to Section 409A, the Committee may, in its sole discretion, take the
actions described in Section 11.1 of the Plan. Notwithstanding any contrary
provision in the Plan or this Agreement, any payment(s) of nonqualified deferred
compensation (within the meaning of Section 409A) that are otherwise required to
be made under this Agreement to a “specified employee” (as defined under
Section 409A) as a result of his or her separation from service (other than a
payment that is not subject to Section 409A) shall be delayed for the first six
(6) months following such separation from service (or, if earlier, the date of
death of the specified employee) and shall instead be paid on the date that
immediately follows the end of such six (6) month period or as soon as
administratively practicable thereafter. A termination of Service shall not be
deemed to have

 

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occurred for purposes of any provision of the Agreement providing for the
payment of any amounts or benefits that are considered nonqualified deferred
compensation under Section 409A upon or following a termination of Service,
unless such termination is also a “separation from service” within the meaning
of Section 409A and the payment thereof prior to a “separation from service”
would violate Section 409A. For purposes of any such provision of this Agreement
relating to any such payments or benefits, references to a “termination,”
“termination of Service” or like terms shall mean “separation from service.”

24. Forfeiture and Clawback. Notwithstanding any other provision of the Plan or
this Agreement to the contrary, by signing this Agreement, the Participant
acknowledges that any incentive-based compensation paid to the Participant
hereunder may be subject to recovery by the Company under any clawback policy
that the Company may adopt from time to time, including without limitation any
policy that the Company may be required to adopt under Section 954 of the
Dodd-Frank Wall Street Reform and Consumer Protection Act and the rules and
regulations of the U.S. Securities and Exchange Commission thereunder or the
requirements of any national securities exchange on which the Shares may be
listed. The Participant further agrees to promptly return any such
incentive-based compensation which the Company determines it is required to
recover from the Participant under any such clawback policy.

[SIGNATURE PAGE FOLLOWS]

 

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

 

SemGroup Corporation By:  

 

Name:   Title:  

 

Agreed and acknowledged as of the date first above written:

 

  Participant

 

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EXHIBIT A

STOCK POWER

FOR VALUE RECEIVED the undersigned hereby sells, assigns and transfers unto
SemGroup Corporation (the “Company”),                      (            ) shares
of the Class A common stock, par value $0.01 per share, of the Company standing
in his/her/their/its name on the books of the Company represented by Certificate
No.                      herewith and does hereby irrevocably constitute and
appoint                      his/her/their/its attorney-in-fact, with full power
of substitution, to transfer such shares on the books of the Company.

 

Dated:                          Signature:  

 

 

Print Name and Mailing Address                      

 

Instructions:   Please do not fill in any blanks other than the signature line
and printed name and mailing address. Please print your name exactly as you
would like your name to appear on the issued stock certificate. The purpose of
this assignment is to enable the forfeiture of the shares without requiring
additional signatures on your part.

 

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