Exhibit 10.1

TESSERA, INC.

March 26, 2010

Bruce M. McWilliams

3025 Orchard Parkway

San Jose, CA
95134



|Re: | Amendment to Consulting Agreement between Bruce M. McWilliams and Tessera, Inc., dated April 3, 2009 (the Agreement)
|--- | ----------------------------------------------------------------------------------------------------------------------

Dear Bruce:

The purpose of
this letter is to amend the Agreement by replacing Exhibit A with the enclosed Exhibit A, effective as of March 31, 2010. All other terms of the Agreement remain unchanged.

If you agree with this Amendment, indicate your acceptance by signing below and initialing the new Exhibit.

Yours very truly,



By:

/s/ Bernard J. CassidyName:

Bernard J. CassidyTitle:

Executive Vice President and General Counsel


AGREED
AND ACCEPTED:



|      |  |                        
|----- |  | -----------------------
|     
|      | 
|By:   |  | /s/ Bruce M. McWilliams
|Name: |  | Bruce M. McWilliams    

Enclosure: Exhibit A



---

EXHIBIT A

DESCRIPTION OF CONSULTING SERVICES

AND COMPENSATION

Services:

Consultant will
provide strategic advice and analysis at the request of the Chief Executive Officer, which may include sales and market analysis, product and business development plans, and merger and acquisition analysis.

Compensation:

Your stock options
and restricted stock grants (set forth below) shall continue to vest pursuant to their original terms for so long as you continue to provide consulting services to the Company, subject to the following conditions:



| | (i) | stock options vesting during the term of this Agreement will be treated as Nonstatutory Stock Options, and to the extent any options vested upon termination of your
employment are not exercised within three months of your employment termination, they will also be treated as Nonstatutory Stock Options, and not as Incentive Stock Options;
| | --- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | (ii) | after this Agreement terminates, you will have ninety (90) days thereafter to exercise any vested options, pursuant to your Stock Option Agreements; and
| | ---- | --------------------------------------------------------------------------------------------------------------------------------------------------------



| | (iii) | upon termination of this Agreement, all unvested stock options and stock grants shall cease vesting, and all unvested options and grants will be cancelled.
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------



|                  |  |               |  |                         |       |         |                 
|----------------- |  | ------------- |  | ----------------------- | ----- | ------- | ----------------
|Grant Date        |  | No. of Shares |  | Exercise Price PerShare |       | Vesting
|Stock Options     |  |               |  |                         |       |         |                 
|08/18/04          |  | 5,633         |  | $                       | 17.75 |         | 1/60th per month
|08/18/04          |  | 224,367       |  | $                       | 17.75 |         | 1/60th per month
|11/22/05          |  | 55,000        |  | $                       | 28.07 |         | 1/48th per month
|05/18/06          |  | 3,546         |  | $                       | 28.20 |         | 1/48th per month
|05/18/06          |  | 96,454        |  | $                       | 28.20 |         | 1/48th per month
|08/27/07          |  | 2,687         |  | $                       | 37.21 |         | 1/48th per month
|08/27/07          |  | 122,313       |  | $                       | 37.21 |         | 1/48th per month
|05/15/08          |  | 125,000       |  | $                       | 19.75 |         | 1/48th per month
|                  |  |               | 
|Restricted Shares |  |               |  |                         |       |         |                 
|05/18/06          |  | 16,000        |  | $                       |      |         | 1/48th per month
|08/27/07          |  | 10,000        |  | $                       |      |         | 1/48th per month

[ /s/bmw ] [ /s/bjc ]

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