Exhibit 10.13

COMMON STOCK WARRANT  THE SCO GROUP, INC.

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NEITHER
THIS WARRANT NOR THE SHARES OF STOCK ISSUABLE UPON EXERCISE HEREOF HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
"ACT"). NO SALE, TRANSFER OR OTHER DISPOSITION OF THIS WARRANT OR SAID SHARES MAY BE EFFECTED WITHOUT (i) AN EFFECTIVE REGISTRATION
STATEMENT RELATED THERETO, (ii) AN OPINION OF COUNSEL SATISFACTORY IN FORM AND SUBSTANCE TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE ACT OR (iii) RECEIPT OF A
NO-ACTION LETTER FROM THE SECURITIES AND EXCHANGE COMMISSION TO THE EFFECT THAT REGISTRATION UNDER THE ACT IS NOT REQUIRED. THE WARRANT EVIDENCED HEREBY IS NON-TRANSFERABLE.

Right
to Purchase 12,500
Shares of Common Stock

The
SCO Group, Inc., a Delaware corporation (the "Company"), hereby certifies that in consideration for early payment of the amount
payable to the Company in August 2003 under the terms of the Software License Agreement dated February 25, 2003 between the Company and Sun Microsystems, Inc., a Delaware
corporation ("Sun"), the receipt in full of which is hereby acknowledged, Sun, or any transferee to whom this warrant (the
"Warrant") is properly transferred in accordance with Section 3(c) below (Sun or any such transferee, the
"Holder"), is entitled, on the terms set forth below, to purchase from the Company at any time during the period commencing on July 31, 2003 (the
"Exercisability Date") and, subject to the provisions of Section 1 below, ending at 5:00 p.m., Pacific time, on July 31, 2008,
12,500 fully paid and nonassessable shares of the common stock, par value $0.001 per share (the "Warrant Shares"), of the Company, at a price of $1.83
per share, subject to adjustments as provided below (the "Purchase Price"). As used herein, the term
"Stock" shall mean the Company's presently
authorized common stock or any stock into or for which such common stock may hereafter be converted or exchanged prior to or concurrent with the exercise of this Warrant.

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| |  | X |  | = |  | Y(A-B)A |  | 
| |  | - |  | - |  | ------- |  | 

where X =

the number of Shares to be issued to the Holder.Y =

the number of Shares subject to this Warrant.A =

the fair market value of one share of the Company's common stock as determined by taking the average of the closing price for the ten most recent trading days ending on the date of exercise.B =

the Exercise Price (as adjusted to the date of such calculation).




3.Representations and Covenants of the Holder.This Warrant has been issued by the Company in reliance upon the following
representations and covenants of the Holder:



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4.Delivery of Stock Certificates on Exercise.Promptly after the exercise of this Warrant and the
payment of the Purchase Price pursuant to Section 2(b) or after the net exercise of this Warrant pursuant to Section 2(c), the Company will issue to the Holder or upon the order
of the Holder hereof, a certificate or certificates for the number of whole shares of Stock to which the Holder is entitled;provided, however,that
(i) the Holder shall have furnished to the Company at the time of such exercise a signed Investment Representation Statement substantially in the form attached hereto as Exhibit Band
(ii) the Company will place on each certificate the following legend:



5.Adjustments for Dividends in Other Stock or Property; Reclassifications.The Purchase Price and
the number and type of Warrant Shares and/or other property issuable upon exercise of this Warrant shall be appropriately and proportionately adjusted to reflect any stock dividend, stock split,
combination of shares, reclassification, recapitalization, any corporate reorganization other than as provided in Section 1 hereof or other similar event affecting the number or character of
outstanding Warrant Shares, so that the number and type of securities and/or other property issuable upon exercise of this Warrant shall be equal to that which would have been issuable with respect to
the number of Warrant Shares subject hereto at the time of such event, had such Warrant Shares then been outstanding.

6.Certificate as to Adjustments.In each case of an adjustment in the Purchase Price or in the
shares of Stock or other stock, securities or property receivable on the exercise of the Warrant, the Company, at its expense, will compute such adjustment in accordance with the terms of the Warrant
and prepare a certificate setting forth such adjustment and showing in detail the facts upon which the adjustment is based. The Company will mail a copy of each such certificate to the Holder of the
Warrant outstanding at that time.

7.Notices of Record Date.In case (i) the Company takes a record of the holders of its Stock
(or other stock or securities at the time receivable upon the exercise of the Warrant) for the purpose of entitling them to receive any dividend or other distribution, or any right to subscribe for or
purchase any shares of stock of any class or any other securities; or (ii) of any capital reorganization of the Company, any reclassification of the common stock of the Company, any
consolidation or merger of the Company with or into another corporation, including, without limitation, any Merger or Consolidation, or any conveyance of all or substantially all of the assets of the
Company to another

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corporation;
or (iii) of any voluntary dissolution, liquidation or winding-up of the Company; then, in each such case, the Company will mail or cause to be mailed to each Holder of
a Warrant at the time outstanding a notice specifying, as the case may be, (a) the date on which a record is to be taken for the purpose of such dividend, distribution or right, and stating the
amount and character of such dividend, distribution or right, or (b) the date on which such reorganization, reclassification, consolidation, merger, conveyance, dissolution, liquidation or
winding-up is to take place, and time, if any is to be fixed, as of which the holders of record of Stock (or such other stock or securities at the time receivable upon the exercise of the
Warrant) will be entitled to exchange their shares of Stock (or such other stock or securities) for securities or other property deliverable upon such reorganization, reclassification, consolidation,
merger, conveyance, dissolution, liquidation or winding-up, and, in the case of a reorganization, consolidation, merger or conveyance, the fair market value of such securities or other
property as determined by the Board of Directors of the Company. Such notice shall be mailed at least ten (10) days prior to the date specified therein; provided, however, that in the event of
a Merger or Consolidation the Company shall use its best efforts to provide such notice in accordance with Section 11 below at least twenty-one (21) days prior to the closing
date of such Merger or Consolidation and, in any event, shall provide such notice in accordance with Section 11 below at least fifteen (15) days prior to such closing date.

8.Reservation of Stock Issuable on Exercise of Warrant.The Company will at all times reserve and
keep available, solely for issuance and delivery upon the exercise of this Warrant, all such shares of Stock and other stock, or such other stock, securities and property as from time to time are
receivable upon the exercise of the Warrant.

9.Exchanges of Warrant.Subject to the provisions of Section 3(c) above, upon surrender for
exchange of this Warrant (in negotiable form, if not surrendered by the Holder named on the face thereof) to the Company at its principal office, the Company, at its expense, will issue and deliver a
new Warrant or Warrants exercisable in the aggregate for the same number of shares of Stock, in the denomination or denominations requested, to or on the order of such Holder upon payment by such
Holder of any applicable transfer taxes;provided, however, that any transferee of the Warrant shall be required to make the representations set forth
inExhibit Battached hereto.

10.Replacement of Warrant.Upon receipt of evidence reasonably satisfactory to the Company of the
loss, theft, destruction or mutilation of this Warrant and (in the case of loss, theft or destruction) upon delivery of an indemnity agreement in such reasonable amount as the Company may determine,
or (in the case of mutilation) upon surrender and cancellation thereof, the Company at its expense, will issue a replacement warrant in substantially identical form to this Warrant.

11.Notices.Any notices, demand, offer, request or other communication required or permitted to be
given by either the Company or a Holder (collectively, a "Notice") pursuant to the terms of this Agreement, if delivered to the Holder, shall be sent to
the following address:



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or
at such other addresses provided to the Company or such other address as a party may request by notifying the other in writing.



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|Dated: August     , 2003 |  | THE SCO GROUP, INC.                                
|------------------------ |  | ---------------------------------------------------
|                         |  | /s/ROBERT K. BENCHSignature of Authorized Signatory
|                         |  | Robert K. Bench, CFOPrint Name and Title           
|Agreed and accepted:     |  |                                                    
|Dated: August     , 2003 |  | SUN MICROSYSTEMS, INC.                             
|                         |  | /s/BRIAN SUTPHINSignature of Authorized Signatory  
|                         |  | Brian Sutphin, Vice PresidentPrint Name and Title  

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EXHIBIT A  NOTICE OF EXERCISE

TO: THE SCO GROUP, INC.

1.     The
undersigned hereby elects to purchase  shares of Common Stock of The SCO Group, Inc pursuant to the
terms
of the attached Warrant.

2.     Exercise
(Please initial the blank):

The undersigned elects to exercise the attached Warrant by means of a cash payment, and tenders herewith payment in full for the purchase price of the shares being purchased, together with all applicable transfer taxes,
if any.The undersigned elects to exercise the attached Warrant by means of a net issue exercise pursuant to Section 2(c) of the Warrant.


3.     Please
issue a certificate, or certificates representing said shares of stock, in the name of the undersigned or in such other name as are specified below:

| |  | (Name)    |  | 
| |  | --------- |  | 
| |  |           |  | 
| |  | (Address) |  | 

4.     The
undersigned represents that the aforesaid shares of stock are being acquired for the account of the undersigned for investment and not with a view to, or for resale
in connection with, the distribution thereof and that the undersigned has no present intention of distributing or reselling such shares. In support thereof, the undersigned has executed an Investment
Representation Statement attached hereto asExhibit B.

| |  | Name of Warrantholder            
| |  | ---------------------------------
| |  | Signature of Authorized Signatory
| |  | Print Name and Title             
| |  | Date                             

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EXHIBIT B  INVESTMENT REPRESENTATION STATEMENT

Shares of Common
Stock
of The SCO Group, Inc.

In
connection with the acquisition of the above-listed securities the undersigned hereby represents to The SCO Group, Inc.(the
"Company") as follows:

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| |  | Name of Warrantholder            
| |  | ---------------------------------
| |  | Signature of Authorized Signatory
| |  | Print Name and Title             
| |  | Date                             

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