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                                                                   EXHIBIT 10.26

                              [TESSERA LETTERHEAD]

April 26, 1999

Dr. Bruce McWilliams

Dear Bruce:

On behalf of the Board of Directors of Tessera, I would like to offer you
employment as President and Chief Executive Officer serving at the pleasure of
Tessera's Board of Directors. This is an exempt position at a starting annual
salary of $230,000. In addition, there will be a bonus plan for you and your
key managers for reaching the Company's key operational and financial goals.
Your bonus would allow earning up to 50% of base pay for the achievement of all
objectives (bonus plan and goals to be more fully developed working with
Tessera's Board of Directors). You will be expected to retain key people, as
well as, to recruit and strengthen Tessera's management team in keeping with the
wishes of the Board of Directors.

In addition to directing the Company's Operations, your responsibilities will
include strategically positioning the Company and leading the Company in the
completion of a successful IPO in the next 18 months with a post transaction
value of at least five hundred million ($500,000,000). In the near term, you
will be responsible for generating an updated business plan and leading a
private financing round sufficient to meet the Company's needs through the end
of the year 2000. In addition to formulating a comprehensive Five Year Sales
Plan, you will be expected to formulate an operating forecast by month for 1999
and to maintain rolling monthly profit and loss forecast for twelve months out.
You will be expected to drive the manufacturing and sales processes and to
assume a key role as the Company positions its dual strategy of Licensing and
Technology Services for an IPO in the 12 to 18 months. As a regular employee,
you will be eligible for certain benefits more fully described in the Tessera
Employee Handbook, which will be issued to you upon your employment.

If you accept this officer, you agree to begin work on June 8, 1999 or sooner
if your other commitments permit. Subject to Board of Directors and shareholder
approvals as required, in addition to your salary you will receive stock
options under the Company's 1999 Incentive Stock Option Plan to purchase two
million two hundred twenty-five thousand (2,250,000) Shares of Tessera Common
Stock at a price set by the Board of Directors upon your acceptance (current
option price is $3.00 per share). Your stock options will be scheduled to vest
as follows:
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[TESSERA LETTERHEAD]                                        Mr. Bruce McWilliams
                                                                  April 26, 1999
                                                                          Page 2

1.    One million three hundred fifty thousand (1,350,000) of your shares will
      be scheduled to vest as follows: 337,500 shares will be scheduled to vest
      on the first anniversary of your employment, and 28,125 shares scheduled
      to vest monthly for thirty six months thereafter.

2.    Upon successful completion of an IPO referenced herein above, the
      remaining nine hundred thousand (900,000) additional shares will be
      layered on the previous vesting schedule for a combined 2,250,000 shares
      vesting as follows: 562,500 shares shall be scheduled to vest on the first
      anniversary of your employment, and 46,875 shall be scheduled to vest
      monthly for thirty six months thereafter.

This offer of employment Option Grant is subject to approval by the Board of
Directors. Your employment pursuant to it is contingent upon your providing
legally required proof of your identity and authorization to work in the United
States and your execution of an Employment Proprietary Information, Invention,
and Arbitration Agreement containing provisions protecting Tessera's
Confidential Information, Inventions, and other Intellectual Property,
including any that you may generate during your employment, along with a notice
that your employment is "at will" and thus can be terminated at any time by you
or Tessera, with or without cause.

By your acceptance of this offer, you represent that: a) you will bring no
confidential information or proprietary intellectual property of any previous
employer or other third party with you to your job at Tessera, b) you will not
solicit for hire any employees of a former employer, and c) you expressly agree
to all the terms of this offer and the terms of the Employment, Proprietary
Information, Invention, and Arbitration Agreement. This offer supersedes any
previous written or verbal offer and shall remain open and valid until May 10,
1999. Any modification of the terms of this offer or other provisions must be
made in writing and signed by Tessera's Chairman of the Board of Directors.

If you accept the above describe offer, please return the signed original copy
of this letter to me. We will send you under separate cover the Employee
Proprietary Information and Inventions Agreement. Please execute and return to
me.

If you have any additional questions please call me at 617.761.1250.

Sincerely,

/s/ ROBERT A. YOUNG

Robert A. Young
Chairman of the Board of Directors

Accepted:    /s/ BRUCE M. McWILLIAMS            Date:     April 27, 1999
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                                                                   EXHIBIT 10.27

                              [TESSERA LETTERHEAD]

July 14, 2000

Dr. Rejeeva Lahri

Dear Rejeeva:

     On behalf of Tessera, I would like to offer you employment as Chief
Operating Officer ("COO") and Sr. Vice President. This is an exempt position at
a starting annual salary of $230,000. In addition, there will be a bonus plan
for you for reaching the Company's operational and financial goals. Your bonus
would allow earning up to 35% of your annual salary for the achievement of all
objectives (bonus plan and goals to be more fully developed by the Tessera
executive management team and ratified by Tessera's Board of Directors).

     Your responsibilities will include all operations in the Company except
Sales, Marketing, Finance, and Legal. You will be expected to provide leadership
and vision at Tessera in the areas of Technology Development and Engineering. In
addition, you will be expected to assume the central responsibility for planning
and executing the company's annual business plan.

     If you accept this offer, you agree to begin work on August 22, 2000 or
sooner if your other commitments permit. You will be reporting directly to me in
my role as Tessera's President and CEO.

     In addition, if you decide to join us, it will be recommended at the next
meeting of the Company's Board of Directors on August 22 that the Company grant
you an option under the Company's 2000 Incentive Stock Option Plan to purchase
775,000 shares of the Company's Common Stock at a price per share equal to the
fair market value per share of the Common Stock on the date of grant, as
determined by the Company's Board of Directors (current option price is $1.75
per share). Your stock options will be scheduled to vest as follows: 193,750
shares will vest on the first anniversary of your employment and 16,146 shares
per month will vest thereafter. This option grant shall be subject to the terms
and conditions of the Company's 2000 Incentive Stock Option Plan and Stock
Option Agreement.

     As an employee, you are also eligible to receive certain employee benefits
including group medical and dental benefits, 401-k plan as well as other
Tessera sponsored benefits. You should note that the Company may modify
salaries and benefits from time to time, as it deems necessary.
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                              [TESSERA LETTERHEAD]

     If your services are no longer required in the role of COO, as described
above, and you elect to leave Tessera, we will pay you six (6) months severance
pay. If your employment is terminated or your responsibilities are substantially
reduced as a result of a change of control of Tessera during your first year of
employment, Tessera will pay you a severance package consisting of a
continuation of your salary and benefits for a six (6) month period and the
remainder of your first year and one additional year of your stock options will
vest. Further, if your employment is terminated or your responsibilities are
substantially reduced due to a change of control during your second year of
employment, Tessera will pay you a severance package consisting of a
continuation of your salary and benefits for a six (6) month period and twelve
(12) additional months of your stock options will vest.

     The Company is excited about your joining and looks forward to a beneficial
and fruitful relationship. Nevertheless, you should be aware that your
employment with the Company is for no specified period and constitutes at-will
employment. As a result, you are free to resign at any time, for any reason or
for no reason. Similarly, the Company is free to conclude its employment
relationship with you at any time, with or without clause, and with or without
notice. We request that, in the event of resignation, you give the Company at
least two weeks notice.

     The Company reserves the right to conduct background investigations and/or
reference checks on all of its potential employees. Your job offer, therefore,
is contingent upon a clearance of such a background investigation and/or
reference check, if any. For purposes of federal immigration law, you will be
required to provide to the Company documentary evidence of your identity and
eligibility for employment in the United States. Such documentation must be
provided to us within three (3) business days of your date of hire, or our
employment relationship with you may be terminated.

     We also ask that, if you have not already done so, you disclose to the
Company any and all agreements relating to your prior employment that may affect
your eligibility to be employed by the Company or limit the manner in which you
may be employed. If is the Company's understanding that any such agreements will
not prevent you from performing the duties of your position and you represent
that such is the case. Moreover, you agree that, during the term of your
employment with the company, you will not engage in any other employment,
occupation, consulting or other business activity directly related to the
business in which the Company is now involved or becomes involved during the
term of your employment, nor will you engage in any other activities that
conflict with your obligations to the Company. Similarly, you agree not to bring
any third party confidential information to the Company, including that of your
former employer, and that in performing your duties for the Company you will not
in any way utilize any such information.

     As a Company employee, you will be expected to abide by company rules and
standards. You will be specifically required to sign an acknowledgment that you
have read and that you understand the Company's rules of conduct which are
included in the Company Handbook. As a condition of your employment, you will
also be required to sign and comply with an

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[TESSERA LETTERHEAD]

Employment, Confidential Information, Invention Assignment and Arbitration
Agreement which requires, among other provisions, the assignment of patent
rights to any invention made during your employment at the Company, and
non-disclosure of proprietary information. The Agreement also provides that in
the event of any dispute or claim relating to or arising out of our employment
relationship, you and the Company agree that all such disputes shall be fully
and finally resolved by binding arbitration.

     To indicate your acceptance of the Company's offer, please sign and date
this letter in the space provided below. A duplicate original is enclosed for
your records. If you accept our offer, your first day of employment will be
August 21, 2000. this letter, along with any agreements relating to proprietary
rights between you and the Company, set forth the terms of your employment with
the Company and supersede any prior representations or agreements, whether
written or oral. This letter, including, but not limited to, its at-will
employment provision, may not be modified or amended except by a written
agreement signed by the Company President and you. This offer of employment
will terminate if it is not accepted, signed and returned by July 21, 2000.

     Rajeeva, both myself and the team are very much looking forward to working
with you and excited about the future we can be build together for the Company.

Best Regards,

/s/ BRUCE McWILLIAMS
-------------------------
Bruce McWilliams
President and CEO

Agreed to and accepted:

Signature:    /s/ RAJEEVA LAMRI
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Printed Name: Rajeeva Lamri
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Date:         July 18, 2000
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Enclosures
  Duplicate Original Letter, Employment, Confidential Information, Invention
  Assignment and Arbitration Agreement

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