Exhibit 10.28


 


HYCROFT MINING CORPORATION

RESTRICTED STOCK UNIT AGREEMENT


(PERFORMANCE-VESTING)


 


THIS AGREEMENT (the “Agreement”)
is made and entered into as of this 20th day of February, 2019 (the “Grant Date”) by and between Hycroft Mining
Corporation, a Delaware corporation (the “Corporation”), and Jeff Stieber (the “Participant”),
pursuant to the Hycroft Mining Corporation Performance and Incentive Pay Plan (the “Plan”). This Agreement and
the award contained herein are subject to the terms and conditions set forth in the Plan, which are incorporated by reference herein,
and the following terms and conditions. Capitalized terms used but not otherwise defined herein shall have the meanings set forth
in the Plan.


 


WITNESSETH:


 


WHEREAS, the Participant
is an employee of the Corporation;


 


WHEREAS, the Corporation
has adopted the Plan in order to promote the interests of the Corporation, its Affiliated Entities and its stockholders by using
stock-based and cash-based incentives to attract, retain and motivate its management and other persons to encourage and reward
such persons contributing to the performance of the Corporation and to align their interests with the interests of the Corporation’s
stockholders;


 


WHEREAS, the Compensation
Committee of the Board (the “Committee”) of the Board of Directors of the Corporation (the “Board”)
has determined that it is in the best interests of the Corporation to grant Restricted Stock Units (as defined herein) under the
Plan to the Participant on the terms and conditions set forth below to encourage the Participant to remain in the employ of the
Corporation, a Subsidiary of the Corporation or an Affiliated Entity and to reward the Participant for his continued employment;
and


 


WHEREAS, the Corporation
is contemplating entering into a transaction with Mudrick Capital Acquisition Corporation, a publicly-traded special purpose acquisition
corporation formed by affiliates of Mudrick Capital (“MUDS”), pursuant to which the Corporation would sell substantially
all of the assets of its subsidiaries and certain of its assets and/or its shares of common stock (a “Sale Transaction”),
and upon consummation of such Sale Transaction the securities issued hereunder shall become convertible into shares of common stock
of MUDS in lieu of and in substitution for shares of the common stock of the Corporation (“Common Stock”).


 


NOW, THEREFORE, in consideration
of the various covenants and agreements herein contained, and intending to be legally bound hereby, the parties hereto agree as
follows:


 


1.                 
Award of Restricted Stock Units. In consideration for the continued service of the Participant to the Corporation
and its Subsidiaries and Affiliated Entities, and as part of the Plan, the Corporation hereby awards to the Participant, subject
to the further terms and conditions set forth in this Agreement, restricted stock units (the “Restricted Stock Units”
or “RSUs”), with a value of $102,500 as of the Grant Date (the “Grant Date Value”).


 






     


     


    

 





2.                 
 No Rights of Stockholder. Until converted as described in Section 6 hereof, the Restricted Stock Units represent
the Corporation’s unfunded and unsecured promise to issue shares of Common Stock, at a future date, subject to the terms
of this Agreement. The Participant has no rights with respect to the Restricted Stock Units other than rights of a general creditor
of the Corporation. Except as set forth in Section 3 hereof, the Participant shall not have any of the rights of a stockholder
with respect to unvested Restricted Stock Units.


 


3.                 
Dividend Equivalents. Subject to the provisions of Section 5 hereof, in the event that the Corporation
declares a dividend on its Common Stock, the Corporation will increase the number of Restricted Stock Units hereunder (i.e.,
by increasing the award) by the number of units, rounded to the nearest whole number, equal to the result of dividing (a) the per
share cash dividend paid by the Corporation on its shares of Common Stock multiplied by the number of unvested Restricted Stock
Units awarded to Participant under this Agreement as of the related dividend payment record date by (b) the fair market value of
one share of Common Stock on the related dividend payment record date.   Any such additional Restricted Stock Units shall
be subject to the same vesting, forfeiture, payment, termination and other terms, conditions and restrictions as the original Restricted
Stock Units to which they relate. No additional Restricted Stock Units shall be granted with respect to any Restricted Stock Units
which, as of the dividend payment record date, have either vested or been terminated. For the avoidance of doubt, these Restricted
Stock Units shall not be entitled to, and no adjustment shall be made, for any distribution of shares of MUDS common stock received
by the Corporation in connection with the Sale Transaction to holders of shares of Common Stock.


 


4.                 
Restrictions on Transfer. Except as otherwise provided in this Agreement, the Participant may not sell, transfer,
assign, pledge, encumber or otherwise dispose of any of the Restricted Stock Units or the rights granted hereunder (any such disposition
or encumbrance being referred to herein as a “Transfer”). Until converted as described in Section 6 hereof,
any Transfer or purported Transfer by the Participant of any of the Restricted Stock Units shall be null and void and the Corporation
shall not recognize or give effect to such Transfer on its books and records or recognize the person to whom such purported Transfer
has been made as the legal or beneficial holder of such Restricted Stock Units. The Restricted Stock Units shall not be subject
to sale, execution, pledge, attachment, encumbrance or other process prior to vesting and no person shall be entitled to exercise
any rights of the Participant as the holder of such Restricted Stock Units by virtue of any attempted execution, attachment or
other process until the Restricted Stock Units are converted as provided in Section 6 hereof.


 


5.                  Vesting
of Restricted Stock Units.Subject to any forfeiture provisions in this Agreement or in the Plan, and subject to Section
5(f) hereof, the Restricted Stock Units shall vest in accordance with the corporate performance metrics set forth in Sections
5(a)-(c). The Restricted Stock Units shall be subject to corporate performance metrics measured over the 2019 calendar
year (the “2019 RSUs”), the 2020 calendar year (the “2020 RSUs”) and the 2021 calendar
year (the “2021 RSUs”). The Participant’s cumulative vested percentage of the Restricted Stock Units
shall be the sum of the vesting percentages earned in Sections 5(a)-(c), provided, however, that the
Participant must be employed with the Corporation or any of its Subsidiaries or Affiliates on the date a corporate
performance metric is determined by the Committee to have been achieved to earn any vesting credit with respect to such
performance metric and provided, further, the closing of the MUDS Sale Transaction is required for any
Restricted Stock Units to vest. The later of (x) the date in which the MUDS Sale Transaction occurs and (y) the date on which
the Committee determines that a corporate performance target has been achieved shall be a “Vesting Date”
with respect to the corresponding Restricted Stock Units.


 






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(a)              
2019 RSUs. The 2019 RSUs represent 33-1/3% of the total number of Restricted Stock Units granted pursuant to Section
1 (the “Awarded RSUs”). The number of 2019 RSUs that vest shall be the sum of the vested percentages earned
in Sections 5(a)(i)-(vii), subject to the additional vesting requirements set forth in the first paragraph of Section
5.


 


(i)                
Operations.


 


	Date by which the First Ore to the Pads is

 Delivered	2019 RSU Vesting

 Percentage
	On or before March 1, 2019	5.0% of the 2019 RSUs
	After March 1, 2019 but on or before

 March 15, 2019	2.5% of the 2019 RSUs
	After March 15, 2019	0.0% of the 2019 RSUs


 


(ii)             
2019 Gold Equivalent Sales. If the amount of 2019 Gold Equivalent Sales is at least 40,000 ounces but less than 50,000
ounces, and if such amount is between sales targets listed below, the 2019 RSU Vesting Percentage earned shall be determined by
linear interpolation.


 


	2019 Gold Equivalent Sales	2019 RSU Vesting 

Percentage
	50,000 ounces or more	27.5% of the 2019 RSUs
	47,334 ounces	20.0% of the 2019 RSUs
	43,667 ounces	12.5% of the 2019 RSUs
	40,000 ounces	7.5% of the 2019 RSUs
	Less than 40,000 ounces	0.0% of the 2019 RSUs


 


(iii)           
Adjusted Cash Cost Per Ounce of Gold Sold. If the Adjusted Cash Cost Per Ounce of Gold Sold is at least $1,000 per
ounce or less but less than $1,150 per ounce, and if such cost is between targets listed below, the 2019 RSU Vesting Percentage
earned shall be determined by linear interpolation.


 









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	Adjusted Cash Cost Per Ounce of Gold 

Sold	2019 RSU Vesting

 Percentage
	$1,000 per ounce or less	27.5% of the 2019 RSUs
	$1,050 per ounce	20.0% of the 2019 RSUs
	$1,100 per ounce	12.5% of the 2019 RSUs
	$1,150 per ounce	7.5% of the 2019 RSUs
	More than $1,150 per ounce	0.0% of the 2019 RSUs


 


(iv)            
Capital Expenditures. If the Corporation’s 2019 Capital Expenditures are at least $11.0 million but less than
$13.0 million, and if such capital expenditures are between targets listed below, the 2019 RSU Vesting Percentage earned shall
be determined by linear interpolation.


 


	2019 Capital Expenditures 	2019 RSU Vesting 

Percentage
	Less than $11.0 million	12.5% of the 2019 RSUs
	$12.0 million	10.0% of the 2019 RSUs
	$13.0 million	7.5% of the 2019 RSUs
	More than $13.0 million	0.0% of the 2019 RSUs


 


(v)              
Updated Feasibility Study.


 


	Date by which an Updated Feasibility 

Study Incorporating Phase III Testwork is 

Successfully Completed	2019 RSU Vesting Percentage
	Prior to April 30, 2019	12.5% of the 2019 RSUs
	After April 29, 2019 but prior to June 30, 2019	10.0% of the 2019 RSUs
	After June 29, 2019 but prior to January 1, 2020	7.5% of the 2019 RSUs
	After December 31, 2019	0.0% of the 2019 RSUs





 






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(vi)            
 Financing.


 


	Date of Execution of MUDS Acquisition 

Agreement	2019 RSU Vesting 

Percentage
	On or before March 31, 2019	15.0% of the 2019 RSUs
	After March 31, 2019 but on or before April 30, 2019	7.5% of the 2019 RSUs
	After April 30, 2019	0.0% of the 2019 RSUs


 


(vii)         
Health, Safety and Environmental.


 


	Date by which EIS is Approved	2019 RSU Vesting 

Percentage
	On or before June 30, 2019	15.0% of the 2019 RSUs
	After June 30, 2019 but on or before 

September 30, 2019	10.0% of the 2019 RSUs
	
        After September 30, 2019 but on
or before

December 31, 2019 
	5.0% of the 2019 RSUs
	After December 31, 2019	0.0% of the 2019 RSUs


 


(b)              
2020 RSUs. The 2020 RSUs represent 33-1/3% of the Awarded Units. The Corporation shall provide the Participant with
the corporate performance metrics and the applicable vesting percentages for the 2020 calendar year before the end of the first
quarter of such year.


 


(c)              
2021 RSUs. The 2021 RSUs represent 33-1/3% of the Awarded Units. The Corporation shall provide the Participant with
the corporate performance metrics and the applicable vesting percentages for the 2021 calendar year before the end of the first
quarter of such year.


 


(d)              
If the application of the vesting schedule in Sections 5(a)-(c) would yield a fractional Restricted Stock Unit, such
fractional Restricted Stock Unit shall be rounded down to the next whole unit if it is less than 0.5 and rounded up to the next
whole unit if it is 0.5 or more.


 


(e)              
Except as described in Section 5(f), to the extent any Restricted Stock Units have not vested upon the earlier of
(i) the last day permitted to earn vesting credit under any performance metric described in Sections 5(a)-(c) or (ii) the
Participant’s Separation from Service for any reason, those Restricted Stock Units that have not vested shall be immediately
forfeited upon such date. Upon such forfeiture, the Participant shall no longer have any rights with respect to such Restricted
Stock Units or any interest therein.


 






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(f)               
 Notwithstanding anything to the contrary in this Section 5, (x) in the event of a Change in Control in which the
resulting entity does not assume, continue, convert or replace this Agreement, the Restricted Stock Units that have not been previously
forfeited shall be fully vested and converted into an equivalent number of shares of Common Stock immediately prior to the Change
in Control, or (y) in the event of a Change in Control where the Participant incurs an involuntary
Separation from Service for any reason other than Cause (as defined in the Plan) within 90 days prior or 24 months following the
Change in Control, the Restricted Stock Units which have not been previously forfeited shall be fully vested and converted into
shares as described in Section 6 and Section 7 hereof. For purposes of this Agreement, the Restricted Stock Units
awarded hereunder will not be considered to be assumed, continued, converted or replaced by the resulting entity in connection
with the Change in Control unless the Restricted Stock Units are adjusted to prevent dilution of the Participant’s rights
hereunder as a result of the Change in Control. For purposes of this Agreement, “Change in Control” shall
have the meaning set forth in the Participant’s Employment Agreement with the Corporation dated February 20, 2019 (the “Employment
Agreement”).


 


6.                 
Conversion of Restricted Stock Units into Common Stock upon Vesting.


 


(a)              
Except as described in Section 6(b) hereof, on the Conversion Date (as defined below), the Restricted Stock Units
that vested pursuant to the terms of Section 5 hereof, if any, shall be converted into the number of shares of Common Stock
equal to the Grant Date Value divided by the fair market value of a share of Common Stock, which shares of Common Stock will be
issued to the Participant, or in the event of the Participant’s death, the Participant’s beneficiary pursuant to the
Plan. Promptly after the Conversion Date, certificates of such shares of Common Stock shall be delivered to the Participant. Except
as provided in Section 11(b), the “Conversion Date” shall be:


 


(i)                
for the 2019 RSUs – the later of the applicable vesting date or December 31, 2020; provided, however,
that if on such date the Participant is prohibited from trading in the Corporation’s securities pursuant to applicable securities
laws and/or the Corporation’s policy on securities trading and disclosure of confidential information, the Conversion Date,
shall be, in the determination of the Committee, the second trading day after the date the Participant is no longer prohibited
from such trading (an “Open Trading Period”); and


 


(ii)             
 for the 2020 RSUs and the 2021 RSUs – the date that is two days after the beginning of the first Open Trading Period
occurring coincident with or after the applicable vesting date.


 


For purposes of this Section 6(a),
the fair market value shall mean the closing price of a share of Common Stock on a national securities exchange on which such shares
of Common Stock may be listed for trading or as determined by the Committee on an applicable vesting date. Notwithstanding anything
to the contrary herein, a Sale Transaction with MUDS, whether in the structure contemplated or another corporate structure, shall
not be deemed to constitute a Change in Control and will not accelerate vesting or conversion of the Restricted Stock Units provided
that the obligations under this Agreement are assumed by MUDS.


 






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(b)              
 In the event of the consummation of the Sale Transaction with MUDS, whether in the structure currently contemplated or
another corporate structure, it shall be a condition to the consummation of the Sale Transaction with MUDS that all obligations
of the Corporation under this Agreement shall be assumed by MUDS and the Restricted Stock Units shall be convertible, subject to
the terms and conditions hereunder, into shares of MUDS common stock following consummation of the Sale Transaction rather than
into shares of Common Stock.


 


7.                 
Adjustment Provisions. If, during the term of this Agreement, there shall be any merger, reorganization, consolidation,
recapitalization, stock dividend, special cash dividend, stock split, reverse stock split, rights offering or extraordinary distribution
with respect to the Common Stock, or other change in corporate structure affecting the Common Stock, the Committee shall make or
cause to be made an appropriate and equitable substitution, adjustment or treatment with respect to the Restricted Stock Units
in a manner consistent with Section 4.3 of the Plan, including a substitution or adjustment in the aggregate number or kind of
shares subject to this Agreement, notwithstanding that the Restricted Stock Units are subject to the restrictions on transfer imposed
by Section 4 above.  Any securities, awards or rights issued pursuant to this Section 7 shall
be subject to the same restrictions as the underlying Restricted Stock Units to which they relate.


 


8.                 
Tax Withholding. As a condition precedent to the receipt of any Restricted Stock Units hereunder, the Participant
agrees to pay to the Corporation, at such times as the Corporation shall determine, such amounts as the Corporation shall deem
necessary to satisfy any withholding taxes due on income that the Participant recognizes pursuant to this Award. The obligations
of the Corporation under this Agreement and the Plan shall be conditional on such payment or arrangements, and the Corporation
and its Subsidiaries and Affiliated Entities shall, to the extent permitted by law, have the right to deduct any such taxes from
any payment otherwise due to the Participant. In addition, the Participant may elect, unless otherwise determined by the Committee,
to satisfy the withholding requirement by having the Corporation withhold shares of Common Stock with a Fair Market Value, as of
the date of such withholding, sufficient to satisfy the withholding obligation.


 


9.                 
Registration. This grant is subject to the condition that if at any time the Board or Committee shall determine,
in its discretion, that the listing of the shares of Common Stock subject hereto on any securities exchange, or the registration
or qualification of such shares under any federal or state law, or the consent or approval of any regulatory body, shall be necessary
or desirable as a condition of, or in connection with, the grant, receipt or delivery of shares hereunder, such grant, receipt
or delivery will not be effected unless and until such listing, registration, qualification, consent or approval shall have been
effected or obtained free of any conditions not acceptable to the Board or Committee. The Corporation agrees to make every reasonable
effort to effect or obtain any such listing, registration, qualification, consent or approval.


 


10.              No
Right to Continued Employment or Engagement. In no event shall the granting of the Restricted Stock Units or the other
provisions hereof or the acceptance of the Restricted Stock Units by the Participant interfere with or limit in any way the
right of the Corporation, a Subsidiary of the Corporation or an Affiliated Entity to terminate the Participant’s
employment or engagement as a service provider at any time, nor confer upon the Participant any right to continue in the
employ or service of the Corporation, a Subsidiary of the Corporation or an Affiliated Entity for any period of time or to
continue his present or any other rate of compensation.


 






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11.             
Section 409A Compliance.


 


(a)              
The intent of the parties is that payments and benefits under this Agreement be excluded from the scope of, or comply with,
Internal Revenue Code Section 409A and the regulations and guidance promulgated thereunder (collectively “Code Section
409A”) and, accordingly, to the maximum extent permitted, this Agreement shall be interpreted as such. To the extent
that any provision hereof is modified in order to comply with Code Section 409A, such modification shall be made in good faith
and shall, to the maximum extent reasonably possible, maintain the original intent and economic benefit to the Participant and
the Corporation of the applicable provision without violating the provisions of Code Section 409A.


 


(b)              
A termination of employment shall not be deemed to have occurred for purposes of any provision of this Agreement providing
for the payment of any amounts or benefits upon or following a termination of employment unless such termination is also a “separation
from service” within the meaning of Code Section 409A and, for purposes of any such provision of this Agreement, references
to a “termination,” “termination of employment” or like terms shall mean “separation from service.”
Notwithstanding anything to the contrary in this Agreement, if the Participant is deemed on the date of termination to be a “specified
employee” within the meaning of that term under Code Section 409A(a)(2)(B), then with regard to any payment or the provision
of any benefit that is considered deferred compensation under Code Section 409A payable on account of a “separation from
service,” such payment or benefit shall not be made or provided until the date which is the earlier of (i) the expiration
of the six (6)-month period measured from the date of such “separation from service” of the Participant, and (ii) the
date of the Participant’s death, to the extent required under Code Section 409A. Upon the expiration of the foregoing delay
period, all payments and benefits delayed pursuant to this Section 11(b) (whether they would have otherwise been payable
in a single sum or in installments in the absence of such delay) shall be paid or reimbursed to the Participant in a lump sum,
and any remaining payments and benefits due under this Agreement shall be paid or provided in accordance with the normal payment
dates specified for them herein.


 


(c)              
For purposes of Code Section 409A, the Participant’s right to receive any installment payments pursuant to this Agreement
shall be treated as a right to receive a series of separate and distinct payments. Whenever a payment under this Agreement specifies
a payment period with reference to a number of days, the actual date of payment within the specified period shall be within the
sole discretion of the Corporation.


 


(d)              
Notwithstanding any other provision of this Agreement to the contrary, in no event shall any payment under this Agreement
that constitutes “nonqualified deferred compensation” for purposes of Code Section 409A be subject to offset by any
other amount unless otherwise permitted by Code Section 409A.


 






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12.             
 Miscellaneous.


 


(a)              
Assignment; Successors. This Agreement will be binding upon and inure to the benefit of the heirs and representatives
of the Participant and the assigns and successors of the Corporation, but neither this Agreement nor any rights hereunder will
be assignable or otherwise subject to hypothecation by the Participant (except by will or by operation of the laws of intestate
succession) or by the Corporation, except that the Corporation may assign this Agreement to any successor (whether by merger, purchase
or otherwise) to all or substantially all of the stock, assets or businesses of the Corporation and, for the avoidance of doubt,
the parties expressly agree that this Agreement shall be assigned to, and assumed by, MUDS in connection with, and as a condition
to, the consummation of the Sale Transaction.


 


(b)              
Governing Law and Forum for Disputes. The laws of the State of Colorado will govern the validity, interpretation,
construction and performance of this Agreement, without regard to the conflict of laws principles thereof. Any action or proceeding
against the parties relating in any way to this Agreement or the Participant’s employment (a “Dispute”)
must be brought and enforced in the courts of the State of Colorado, and the parties irrevocably (i) submit to the jurisdiction
of such courts in respect of any such action or proceeding and (ii) waive any right to a trial by jury of any Dispute.


 


(c)              
Modification or Amendment. No failure or delay by the Corporation or the Participant in enforcing or exercising any
right or remedy hereunder will operate as a waiver thereof. No provisions of this Agreement may be modified, waived, or discharged
except by a written document signed by an officer or director of the Corporation duly authorized by the Board and the Participant.


 


(d)              
Notices. Notices given pursuant to this Agreement will be in writing and will be deemed received when personally
delivered, or on the date of written confirmation of receipt by (i) overnight carrier, (ii) facsimile with confirmation of delivery,
(iii) registered or certified mail, return receipt requested, addressee only, postage prepaid, or (iv) such other method of delivery,
including electronic transmission, that provides a written confirmation of delivery. Notice to the Corporation will be directed
to:


 


Hycroft Mining Corporation


c/o Randy Buffington

President and Chief Executive Officer

8181 E. Tufts, Suite 510

Denver, CO 80237


 


with a copy to:


 


Neal, Gerber & Eisenberg, LLP

2 N. LaSalle Street, Suite 1700

Chicago, IL 60602

Attention: David S. Stone, Esq.

email: dstone@nge.com


 






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The Corporation may change the person and/or
address to whom the Participant must give notice under this Section 12(d) by giving the Participant written notice of such
change, in accordance with the procedures described above. Notices to or with respect to the Participant will be directed to the
Participant, or to the Participant’s executors, personal representatives or distributees, if the Participant is deceased,
at the Participant’s home address on the records of the Corporation, or such other address provided to the Corporation in
accordance with the procedures described above.


 


(e)              
Severability. If any provisions of this Agreement will be found invalid or unenforceable by a court of competent
jurisdiction, in whole or in part, then it is the parties’ mutual desire that such court modify such provision(s) to the
extent and in the manner necessary to render the same valid and enforceable, and this Agreement will be construed and enforced
to the maximum extent permitted by law, as if such provision(s) had been originally incorporated herein as so modified or restricted,
or as if such provision(s) had not been originally incorporated herein, as the case may be.


 


(f)               
Entire Agreement. The Participant acknowledges receipt of this Agreement and agrees that with respect to the Restricted
Stock Units (Performance Vesting), it contains the entire understanding and agreement with the Corporation, superseding any previous
oral or written communication, representation, understanding or agreement with the Corporation or any representative thereof. No
term or condition should be construed strictly against any party on the basis that it was drafted by such party.


 


(g)              
Headings. The headings in this Agreement are for convenience of reference only and will not limit or otherwise affect
the meaning thereof.


 


(h)              
Counterparts.  This Agreement may be executed in any number of counterparts, including by facsimile or PDF,
each of which shall be deemed an original, and all of which shall constitute one and the same instrument.


 


[Signature page to follow]


 






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IN WITNESS WHEREOF,
each of the parties hereto has executed this Agreement as of the Grant Date.


 


	 	 	 
	PARTICIPANT	 	HYCROFT MINING CORPORATION
	 	 	 
	/s/ Jeff
Stieber	 	/s/ Randy
    Buffington
	Jeff Stieber	 	By:	Randy Buffington
	 	 	Its: 	President & CFO  





 






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