QuickLinks -- Click here to rapidly navigate through this document

Exhibit 10.6


REGISTRATION RIGHTS AGREEMENT

        This Registration Rights Agreement (this "Agreement") is entered into effective the 25th day of May 1999, by and between PROS Strategic Solutions, Inc., a Delaware corporation (the "Company"), and David Samuel Coats (the "Stockholder").

W I T N E S S E T H:

        WHEREAS, the Company and the Stockholder have entered into that certain Separation Agreement of even date herewith (the "Separation Agreement"); and

        WHEREAS, pursuant to the Separation Agreement, the Stockholder will retain 325,000 shares (the "Retained Shares") of the common stock, $.001 par value per share ("Common Stock"), of the Company; and

        WHEREAS, the Separation Agreement contemplates the execution of this Agreement to provide to the Stockholder certain registration rights in respect of the Retained Shares;

        NOW, THEREFORE, in consideration of the premises and the mutual covenants and conditions herein contained, the parties do hereby agree as follows:

        1.    Registration Rights.    The parties covenant and agree as follows:

1


2


3


        2.    Notices.    All notices, requests, consents, and other communications under this Agreement shall be in writing and shall be delivered by hand, or mailed by first class certified or registered mail, return receipt requested, postage prepaid, to the Company and the Stockholder at their respective addresses set forth below:


If to the Company:

 

PROS Strategic Solutions, inc.
3223 Smith Street, Suite 100
Houston, Texas 77006
Attention: President

If to the Stockholder:

 

Mr. David Samuel Coats
7 Marilane
Houston, Texas 77007

Any party may change its address for purposes hereof by notice to the other party in the manner provided above.

4



        3.    Amendments and Waivers.    Except as otherwise provided in this Agreement, the terms and provisions of this Agreement may not be modified or amended except in a writing executed by the Company and the Stockholder. No waivers of or exceptions to any term, condition or provision of this Agreement, in any one or more instances, shall be deemed to be, or construed as, a further or continuing waiver of any such term, condition or provision.

        4.    Entire Agreement.    With respect to the subject matter hereof, this Agreement embodies the entire agreement and understanding between the Stockholder and the Company.

        5.    Counterparts.    This Agreement may be executed in several counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

        6.    Headings.    The headings of the sections, subsections and paragraphs of this Agreement have been added for convenience only and shall not be deemed to be a part of this Agreement.

        7.    Severability.    Any provision of this Agreement which is invalid or unenforceable in any jurisdiction shall be ineffective to the extent of such invalidity or unenforceability without invalidating or rendering unenforceable the remaining provisions of this Agreement, and, to the extent permitted by law, any determination of invalidity or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction.

        8.    Assignment.    Neither this Agreement nor any of the rights or obligations of the Stockholder or the Company provided herein may be assigned, sold, pledged, hypothecated or otherwise transferred by the Stockholder without the prior written consent of the Company. This Agreement shall inure to the benefit of and be binding upon the respective heirs, personal representatives, successors and permitted assigns of the parties.

        9.    Governing Law.    This Agreement shall be governed by and construed in accordance with the laws of the State of Texas without reference to its principles of conflicts of law.

        IN WITNESS WHEREOF, the undersigned have hereunto set their hands as of the day and year first above written.


 

 

"
Company"

 

 

PROS STRATEGIC SOLUTIONS, INC.

 

 

By:

/s/ Charles H. Murphy

Charles H. Murphy
CFO

 

 

"
Stockholder"

 

 

/s/ David Samuel Coats

David Samuel Coats

5




QuickLinks

REGISTRATION RIGHTS AGREEMENT