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                                                                  EXHIBIT 10.29

               ADDENDUM TO SECURITY AGREEMENT: SECURITIES ACCOUNT

        THIS ADDENDUM is attached to and made a part of that certain Security
Agreement: Securities Account executed by HANDSPRING, INC ("Debtor") in favor of
WELLS FARGO BANK, NATIONAL ASSOCIATION ("Bank"), dated as of February 16, 2001
(the "Agreement").

        The following provisions are hereby incorporated into the Agreement:

        1. Securities Account Activity. So long as no Event of Default exists,
Debtor, or any party authorized by Debtor to act with respect to the Securities
Account, may (a) receive payments of interest and/or cash dividends earned on
financial assets maintained in the Securities Account, and (b) trade financial
assets maintained in the Securities Account. Without Bank's prior written
consent, except as permitted by the preceding sentence, neither Debtor nor any
party other than Bank may withdraw or receive any distribution of any Collateral
from the Securities Account. The Collateral Value of the Securities Account
shall at all times be equal to or greater than one hundred percent (100%) of the
aggregate amount available to be drawn under all outstanding letters of credit
issued by Bank or any of its affiliates for the account of Debtor plus amounts
drawn thereunder and not yet reimbursed to Bank. In the event that the
Collateral Value, for any reason and at any time, is less than the required
amount, Debtor shall promptly make a principal reduction on the Indebtedness or
deposit additional assets of a nature satisfactory to Bank into the Securities
Account, in either case in amounts or with values sufficient to achieve the
required Collateral Value.

        2. "Collateral Value" means the percentage set forth below for each type
of investment property held in the Securities Account at the time of
computation:

        (a)    100% of the face amount of cash and cash equivalents;

        (b)    90% of the market value of obligations of the United States of
               America, but not to exceed the face amount;

        (c)    90% of the market value of commercial paper rated at least A1 by
               a nationally recognized rating agency, but not to exceed the face
               amount;

with market value, in all instances, determined by Bank in its sole discretion,
and excluding from such computation all WF Securities and Common Trust Funds.

        3. Exclusion from Collateral. Notwithstanding anything herein to the
contrary, the terms "Collateral" and "Proceeds" do not include, and Bank
disclaims a security interest in all WF Securities and Common Trust Funds now or
hereafter maintained in the Securities Account.

        4. "Common Trust Funds" means common trust funds as described in 12 CFR
9.18 and includes, without limitation, common trust funds maintained by Bank for
the exclusive use of its fiduciary clients.

        5. "WF Securities" means stock, securities or obligations of Wells Fargo
& Company or of any affiliate thereof (as the term affiliate is defined in
Section 23A of the Federal Reserve Act (12 USC 371(c), as amended from time to
time).

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        IN WITNESS WHEREOF, this Addendum has been executed as of the same date
as the Agreement.

HANDSPRING, INC                              WELLS FARGO BANK,
                                                 NATIONAL ASSOCIATION

By: /s/  Bernard Whitney
    ------------------------------
Title: CFO                                   By: /s/  Jill B. Ta
       ---------------------------               -------------------------------
                                             Title: Vice President
                                                    ----------------------------
By: /s/  David Pine
    ------------------------------
Title:  VP, General Counsel
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                                                                    Exhibit 10.1

                            U.S. LABORATORIES INC.

                           1999 STOCK INCENTIVE PLAN

1.   Purposes of The Plan

     The U.S. Laboratories Inc. 1999 Incentive Plan (the "Plan") is established
to promote the interests of U.S. Laboratories Inc., a Delaware corporation (the
"Company"), by creating an incentive program to (a) attract and retain employees
who will strive for excellence and (b) motivate those individuals to set and
achieve above-average objectives by providing them with rewards for
contributions to the operating profits and earning power of the Company.

2.   Administration of The Plan

     The Compensation Committee of the Board of Directors of the Company (the
"Committee") will administer the Plan and adopt rules and regulations to
implement the Plan.  Decisions of the Committee are final and binding on all
parties who have an interest in the Plan.  In the absence of a Compensation
Committee, the Board of Directors will administer the Plan.

3.   Definitions.  For purposes of the Plan:

     3.1.  Employee.  An individual shall be considered an "Employee" while the
individual remains employed by the Company or one or more of its Subsidiaries.

     3.2.  Subsidiary.  Each corporation (other than the Company) in an unbroken
chain of corporations beginning with the Company shall be considered to be a
"Subsidiary" of the Company, provided each such corporation (other than the last
corporation in the unbroken chain) owns, at the time of determination, stock
possessing more than 50% of the total combined voting power of all classes of
stock in one of the other corporations in such chain.

4.   Stock Subject to Plan

     4.1.  Number.  Subject to adjustment as provided in Section 4.2, the total
number of shares of the Company's common stock that may be issued under the Plan
is 100,000.  The shares to be delivered under the Plan may consist, in whole or
in part, of authorized but unissued stock or treasury stock.

     4.2.  Adjustment in Capitalization.  If the Committee determines that any
dividend or other distribution (whether in the form of cash, stock, other
securities or other property), recapitalization, stock split, reverse stock
split, reorganization, merger, consolidation, split-up, spin-off, combination,
repurchase or exchange of stock or other securities of the Company, issuance of
warrants or other rights to purchase stock or other securities of the Company,
or other similar corporate transaction or event affects the stock and the
Committee determines that an adjustment is appropriate in order to prevent
dilution or enlargement of the benefits or potential benefits intended to be
made available under the Plan, then the Committee may adjust

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any or all of (i) the number and type of shares of stock subject to the Plan and
which thereafter may be made the subject of awards under the Plan; (ii) the
number and type of shares of stock subject to outstanding awards; and (iii) the
grant, purchase or exercise price with respect to any award, or, if deemed
appropriate, make provision for a cash payment to the holder of an outstanding
award.

5.   Bonus Awards

     5.1.  Eligibility.  All employees of the Company and its subsidiaries are
eligible under the Plan.

     5.2.  Allocations. The Committee will determine the bonus pool and
allocations to be paid under the Plan for the Company's fiscal year. These
allocations will be reviewed and approved by the Board of Directors prior to
grant of the bonus. The determinations of the Committee and the Board are final.

     5.3.  The Committee may restrict the resale of the bonus shares by
Employees for up to one year from the date of the grant.

     5.4.  Entitlement to Bonus.  The Committee will determine who will receive
allocations under the Plan.  This determination will be reviewed and approved by
the Board of Directors.  If an eligible Employee receives no allocation under
section 5.1 above, then that Employee is not entitled to any bonus under the
Plan.

6.   Payment Of Bonus Awards

     6.1.  The bonus awards may be paid in cash or shares of the Company's
common stock at the discretion of the Committee and the Board of Directors.

     6.2.  The individual bonus award allocated to each Employee under Section 5
will be paid to the Employee within 30 days after completion of the annual audit
of the Company's financial statements by its independent auditors, regardless of
whether the individual has remained in Employee status through the date of
payment.

7.   Valuation of Stock.  The Committee will place a value on the stock in order
     to determine the compensation received by employees.

8.   Withholding.  The Company may withhold taxes owed by Employee.

9.   Term.  This Plan will expire ten (10) years from the date of its adoption,
     unless extended by the Board of Directors.

10.  General Provisions

     10.1.  Plan Amendments.  The Plan will become effective when adopted by the
Company's Board of Directors.  The Board of Directors may at any time amend,
suspend or terminate the Plan, provided that it must do so in a written
resolution and the action may not

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adversely affect rights and interests of Plan participants to individual bonuses
allocated prior to such amendment, suspension or termination.

10.2.  Benefits Unfunded.  No amounts awarded or accrued under this Plan are
actually funded, set aside or otherwise segregated prior to payment.  The
obligation to pay the bonuses awarded hereunder shall at all times be an
unfunded and unsecured obligation of the Company.  Plan participants shall have
the status of general creditors and shall look solely to the general assets of
the Company for the payment of their bonus awards.

10.3.  Benefits Nontransferable.  No Plan participant has the right to alienate,
pledge or encumber his or her interest in this Plan, and this interest may not
(if permitted by law) be subject in any way to the claims of the Employee's
creditors or to attachment, execution or other process of law.

10.4.  No Employment Rights.  No action of the Company in establishing the Plan,
no action taken under the Plan by the Committee and no provision of the Plan
itself may be construed to grant any person the right to remain in the employ of
the Company or its subsidiaries for any period of specific duration.  Rather,
each Employee will be employed "at will," which means that either such Employee
or the Company may terminate the employment relationship at any time and for any
reason, with or without cause.

10.5.  Exclusive Agreement.  This Plan document is the full and complete
agreement between the eligible Employees and the Company on the terms described
herein.

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