<PAGE>

                                                      Composite consisting
                                                      of 1994 Revision and
                                                      Amendments 1-5


                             GENUITY SAVINGS PLAN
<PAGE>

ARTICLE                                                                   PAGE
-------                                                                   ----
Article  1. Introduction................................................     1
         1.1.  Purpose..................................................     1
         1.2.  Effective Date...........................................     1

Article  2. Definitions.................................................     2
         2.1.  Account..................................................     2
         2.2.  Administrator............................................     3
         2.3.  Affiliated Employer......................................     3
         2.3A. Allocation Period........................................     4
         2.4.  Annual Addition..........................................     4
         2.5.  Beneficiary..............................................     4
         2.6.  Board of Directors.......................................     5
         2.7.  Code.....................................................     5
         2.8.  Company..................................................     5
         2.9.  Computation Period.......................................     5
         2.10. Credited Compensation....................................     5
         2.11. Effective Date...........................................     6
         2.12. Eligible Employee........................................     7
         2.13. Employee.................................................     7
         2.14. Employee After-Tax Contribution..........................     7
         2.15. Employer.................................................     7
         2.16. Employment Commencement Date.............................     7
         2.17. ERISA....................................................     8
         2.18. 401(k) Credited Compensation.............................     8
         2.19. Hours of Service.........................................     8
         2.20. Investment Fund..........................................     8
         2.21. Matching Contribution....................................     8
         2.22. Participant..............................................     9
         2.23. Participating Employer...................................     9
         2.24. Plan.....................................................     9
         2.25. Plan Year................................................     9
         2.26. Pre-Tax Contribution.....................................    10
         2.27. Primary Contribution.....................................    10
         2.28. Prior Plan...............................................    10
         2.29. Qualified Domestic Relations Order.......................    10
         2.30. Rollover Contribution....................................    11
         2.31. Service..................................................    11

                                      -i-
<PAGE>

ARTICLE                                                                   PAGE
-------                                                                   ----

         2.32. Share of the Trust Fund..................................    12
         2.33. Stock....................................................    12
         2.34. Termination of Employment Date...........................    12
         2.35. Trust....................................................    12
         2.36. Trust Fund...............................................    12
         2.37. Trustees.................................................    12
         2.38. Trustees' Fund...........................................    12

Article  3. Administration..............................................    14
         3.1.  Administrator............................................    14
         3.2.  Powers and discretionary authority.......................    14
         3.3.  Examination of records...................................    15
         3.4.  Nondiscriminatory exercise of authority..................    16
         3.5.  Reliance on tables, etc..................................    16
         3.6.  Named fiduciary..........................................    16
         3.7.  Expenses of Plan.........................................    16
         3.8.  Claims and review procedures.............................    17
         3.9.  Indemnification of Administrator.........................    18

Article  4. Participation...............................................    19
         4.1.  Date of participation....................................    19
         4.2.  Cessation of participation...............................    19
         4.3.  Reemployment of a former Participant.....................    19

Article  5. Contributions...............................................    21
         5.1.  Primary Contributions....................................    21
         5.2.  Pre-Tax Contributions....................................    22
         5.3.  Form and manner of Pre-Tax Contribution elections........    22
         5.4.  Matching Contributions...................................    24
         5.5.  Employee After-Tax Contributions.........................    24
         5.6.  Rollover Contributions...................................    24
         5.7.  Other transfers..........................................    25
         5.8.  Time for making contributions............................    25
         5.9.  Certain limits apply.....................................    26
         5.10. Return of contributions..................................    26

                                      -ii-
<PAGE>

ARTICLE                                                                   PAGE
-------                                                                   ----

Article  6. Investments.................................................    27
         6.1.  Investment of contributions..............................    27
         6.2.  Investment of income.....................................    27
         6.3.  Change of election by Participant........................    28
         6.4.  Investment Fund for certain Matching Contributions.......    28

Article  7. Participants' Accounts......................................    30
         7.1.  Individual accounts......................................    30
         7.2.  Crediting of contributions...............................    30
         7.3.  Treatment of forfeitures.................................    30
         7.4.  Adjustments to individual accounts.......................    31
         7.5.  Eligibility to share in Primary Contributions and
               supplemental Matching Contributions......................    31
         7.6.  Rights of Participants...................................    33

Article  8. Limits on Contributions.....................................    34
         8.1.  Deductibility of Contributions...........................    34
         8.2.  Nondiscrimination limitations............................    34
         8.3.  Limit on Annual Additions................................    34

Article  9. Benefits Because of Age or Disability.......................    36
         9.1.  Normal retirement........................................    36
         9.2.  Disability retirement....................................    36

Article 10. Benefits Because of Death...................................    37
        10.1.  Distribution of benefits upon death......................    37
        10.2.  Designation of Beneficiary...............................    37

Article 11. Benefits Because of Separation from Service.................    39
        11.1.  Separation from service..................................    39
        11.2.  Termination benefit......................................    39
        11.3.  Election of former vesting schedule......................    39
        11.4.  Forfeitures..............................................    40
        11.5.  Separate account.........................................    42

Article 12. Withdrawals; Hardship Distributions; Loans..................    43
        12.1.  Withdrawal of Employee After-Tax Contributions...........    43
        12.2.  Hardship withdrawals.....................................    43
        12.3.  Loans....................................................    45

                                     -iii-
<PAGE>

ARTICLE                                                                   PAGE
-------                                                                   ----

Article 13. Distribution of Benefits....................................    51
        13.1.  Methods of making distributions..........................    51
        13.2.  Distributions............................................    51
        13.3.  Latest commencement date for benefits....................    52
        13.4.  Cessation of interest in Plan............................    54

Article 14. Direct Rollovers of Eligible Distributions..................    55
        14.1.  In General...............................................    55
        14.2.  Definitions..............................................    55
        14.3.  Notice requirement.......................................    56

Article 15. Special Top Heavy Provisions................................    57

Article 16. Concerning the Trustees.....................................    58
        16.1.  Appointment of Trustee...................................    58
        16.2.  Powers of the Trustees...................................    58
        16.3.  Voting of Stock and other securities.....................    63
        16.4.  Indemnification of Trustees..............................    63
        16.5.  Compensation of Trustees and expenses of Plan and Trust..    63
        16.6.  Limits of Trustees' duties...............................    64
        16.7.  Reliance by Trustees on other persons....................    64
        16.8.  Consultation by Trustees with counsel....................    65
        16.9.  Resignation or removal...................................    66
        16.10. Appointment of successor Trustee.........................    66
        16.11. Approval of accounts.....................................    66
        16.12. Dispute as to persons entitled to payment................    67
        16.13. Action by majority.......................................    67

Article 17. Amendment...................................................    68

Article 18. Discontinuance of Contributions and Termination of Plan.....    69
        18.1.  Termination of Plan by Company...........................    69
        18.2.  Events resulting in termination of Plan..................    69
        18.3.  Termination of participation as to any Participating
               Employer or group of Participants........................    70
        18.4.  Permanent discontinuance of contributions................    70
        18.5.  Merger or consolidation of Plan; transfer of Plan assets.    71

                                      -iv-
<PAGE>

ARTICLE                                                                   PAGE
-------                                                                   ----

Article 19. Miscellaneous.................................................  72
        19.1.  Limitation of rights.......................................  72
        19.2.  Benefits provided solely from Trust........................  72
        19.3.  Nonalienability of benefits................................  72
        19.4.  Payment under Qualified Domestic Relations Orders..........  73
        19.5.  Acceptance of Trust; governing law.........................  73
        19.6.  Method of providing notice.................................  73
        19.7.  Compliance with USERRA, etc................................  74
        19.8.  Compliance with Code (S) 401(a), (S) 401(k), etc...........  75
        19.9.  Certain trustee-to-trustee transfers.......................  75

APPENDIX I -- SPECIAL RULES RELATING TO (S) 401(k) AND (S) 401(m) TESTING.  78
         I.1.  In General.................................................  78
         I.2.  Certain Definitions........................................  78
         I.3.  Dollar limit on Pre-Tax Contributions......................  79
         I.4.  ADP Tests, etc.............................................  80
         I.5.  ACP Tests, etc.............................................  84

APPENDIX II -- SPECIAL TOP HEAVY PROVISIONS  89
         II.1. Provisions to apply........................................  89
         II.2. Minimum Contribution.......................................  89
         II.3. Special Vesting Schedule...................................  89
         II.4. Definitions................................................  90

APPENDIX III -- SALE OF ADVANCED SIMULATION BUSINESS......................  92

APPENDIX IV -- SALE OF LIGHTSTREAM BUSINESS...............................  93


                                      -v-
<PAGE>

                              GENUITY SAVINGS PLAN

     Pursuant to the provisions of Article 16 of the Genuity Savings Plan, said
Agreement, as amended, is hereby further amended and restated to read as
follows:

Article  1.    Introduction.
               ------------

         1.1.  Purpose.  The purpose of this Trust is to provide retirement and
other benefits in accordance with the Plan set forth herein. Subject to the
provisions of Sections 5.10 and 8.3, no part of the principal or income of this
Trust may be used for, or diverted to, purposes other than for the exclusive
benefit of the Participants, former Participants or their beneficiaries. The
Plan set forth herein is a discretionary contribution plan with a cash or
deferred arrangement and provision for matching contributions and after-tax
employee contributions.

         1.2.  Effective Date.  Except as otherwise expressly provided, the
provisions of this restatement are effective as of July 1, 1994.

                                      -1-
<PAGE>

Article 2.     Definitions.
               -----------

     Wherever used herein, unless the context clearly indicates otherwise, the
following words have the following meanings:

         2.1.  Account.  "Account" means any or all of the following, as the
context requires:

               (a)  "Employee After-Tax Contribution Account": the account or
     sub-account established and maintained to reflect a Participant's Employee
     After-Tax Contributions under Section 5.5 or under the Prior Plan, as
     periodically adjusted for investment experience.

               (b)  "Pre-Tax Contribution Account": the account or sub-account
     established and maintained to reflect Pre-Tax Contributions made under
     Section 5.2 for the benefit of a Participant, as periodically adjusted for
     investment experience.

               (c)  "Primary Contribution Account":  the account or sub-account
     established and maintained to reflect Participating Employer contributions
     under the Prior Plan and discretionary Participating Employer contributions
     under Section 5.1 of this Plan, as periodically adjusted for investment
     experience.  In the case of a Participant for whose benefit contributions
     were made under the qualified cash-or-deferred feature of the Prior Plan,
     there shall be maintained within the Participant's Primary Contribution
     Account a separate sub-account to reflect such contributions and associated
     investment experience.

               (d)  "Matching Contribution Account":  the account or sub-account
     established and maintained to reflect Participating Employer matching
     contributions under Section 5.4 of the Plan.

                                      -2-
<PAGE>

               (e)  "Rollover Account": in the case of any Eligible Employee who
     contributes an "eligible rollover distribution" (whether by direct transfer
     or otherwise) to the Plan under Section 5.6, an account or sub-account
     established and maintained to reflect such contribution and associated
     investment experience.

               (f)  "Transfer Account": in the case of any Eligible Employee
     whose accrued benefit under another plan is transferred directly to the
     Plan in a nonelective trust-to-trust transfer described in Section 414(l)
     of the Code and Section 5.7 of the Plan, an account or sub-account
     maintained to reflect such transferred amount and associated investment
     experience.

The Trustees and the Administrator may maintain such other accounts and records
as may reasonably be required to discharge their duties under the Plan.

         2.2.  Administrator.  "Administrator" means the committee appointed to
administer the Plan in accordance with Article 3.

         2.3.  Affiliated Employer.  "Affiliated Employer" means (i) any
corporation (other than the Company) which is a member of a controlled group of
corporations (as defined in Code (S) 414(b)) with the Company; (ii) any trade or
business (other than the Company), whether or not incorporated, which is under
common control (as defined in Code (S) 414(c)) with the Company; (iii) any
member (other than the Company) of an affiliated service group (as defined in
Code (S) 414(m)) of which the Company is a member; and (iv) any other employer
required to be aggregated with the Company under Code (S) 414(o). To the extent
specified in writing by the Chairman or the Treasurer of the Company, the term
"Affiliated Employer" shall also be deemed

                                      -3-
<PAGE>

to include any corporation, trade or business that would be described in (i) or
(ii) above if the affiliation rules referred to in Code (S) 414(b) and (S)
414(c) were applied by substituting "more than 50%" for "80%".

         2.3A  Allocation Period.  "Allocation Period" or "Allocation Periods"
means, for any Plan Year, the period or periods within such Plan Year with
respect to which Primary Contributions (if any) and allocations thereof will be
made for such Plan Year.  Except as otherwise determined by the Board of
Directors prior to the beginning of the Plan Year of reference, a Plan Year
shall consist of two Allocation Periods, one commencing January 1 and ending
June 30 and the other commencing July 1 and ending December 31.  If the Board of
Directors so determines prior to the beginning of the Plan Year of reference,
however, a Plan Year may consist of a single Allocation Period that is
coextensive with the Plan Year or may consist of consecutive monthly or
quarterly Allocation Periods.

         2.4.  Annual Addition.  "Annual Addition" means, in the case of any
Participant, when used with respect to the Plan, the sum for any Plan Year of
(a) the Pre-Tax Contributions, Matching Contributions, and Primary Contributions
made by the Employer for the Participant's benefit under the Plan, (b) the
Participant's Employee After-Tax Contributions under the Plan, and (c)
forfeitures, if any, allocated to the Participant's Accounts under the Plan.

         2.5.  Beneficiary.  "Beneficiary" means the person or persons
designated by a Participant or former Participant to receive benefits under the
Plan upon the death of the Participant or former Participant.

                                      -4-
<PAGE>

         2.6.  Board of Directors.  "Board of Directors" means the Board of
Directors of the Company. The Board of Directors may designate a person or
persons (including a committee) to carry out any fiduciary responsibilities of
the Company or of the Board under the Plan, any such designation to be made in
accordance with Section 405 of ERISA.

         2.7.  Code.  "Code" means the Internal Revenue Code of 1986, as amended
and in effect from time to time. Reference to any section or subsection of the
Code includes reference to any comparable or succeeding provisions of any
legislation which amends, supplements or replaces such section or subsection.

         2.8.  Company.  "Company" means Genuity Inc. and any successor to all
or a major portion of its assets or business which assumes the obligations of
the Company.

         2.9.  Computation Period.  "Computation Period" means a period of
twelve (12) consecutive months beginning with the Employee's Employment
Commencement Date and each anniversary thereof.

         2.10. Credited Compensation.  "Credited Compensation" means the regular
base compensation received by an Eligible Employee while he is Participant,
modified as provided at (a), (b) and (c) below. Any amount that would qualify as
Credited Compensation but for the Participant's agreement to forgo receipt of
such amount pursuant to a salary reduction agreement or pursuant to a cafeteria
plan (within the meaning of Code 125) shall be treated as Credited Compensation
for purposes of the Plan. In no event shall Credited Compensation in excess of
the limitation determined under Code (S) 401(a)(17) be taken into account under
the Plan, and

                                      -5-
<PAGE>

Eligible Employees with Credited Compensation in excess of such limit shall have
their Credited Compensation limited on a per pay period basis to comply with
such limit.

               (a)  Credited Compensation shall include sales commissions, sales
     bonuses, foreign service premiums, lump sum merit increases, temporary job
     reclassification pay adjustments that are paid to the Participant for a
     period of at least ninety (90) consecutive days, and payments made under
     other short-term incentive programs that are specifically included by the
     Administrator from time to time.

               (b)  Credited Compensation shall not include (except to the
     extent expressly included pursuant to (a) above) any commissions, Executive
     Incentive Plan payments, other management incentives, other incentive
     payments, awards, profit-sharing, stock received pursuant to stock option
     plans or other stock purchase plans, bonuses, overtime, shift or other
     premiums, supplemental vacation benefits, moving expense reimbursements, or
     any other special fees or allowance paid to an Employee during a Plan Year.

               (c)  To the extent expressly provided in any written separation
     policy of the Company or a Participating Employer, Credited Compensation
     shall include any salary continuation payments from the general assets of
     the Company or the Participating Employer that an Employee receives
     pursuant to the policy.

         2.11. Effective Date.  "Effective Date" means the date or dates
referred to in Section 1.2.

                                      -6-
<PAGE>

         2.12. Eligible Employee.  "Eligible Employee" means any individual
(including an officer or employee director of a Participating Employer) who is
employed by a Participating Employer, other than (i) a nonresident alien who
receives no earned income (within the meaning of Code (S) 911(d)(2)) from a
Participating Employer which constitutes income from sources within the United
States (within the meaning of Code (S) 861(a)(3)), or (ii) a leased employee
(within the meaning of Code (S) 414(n)(2)). For the avoidance of doubt, (A) no
individual shall be treated as an Eligible Employee during any period in which
he or she is treated as an independent contractor for payroll purposes by the
Employer, regardless of any later recharacterization of such individual's
employment status, and (B) in determining whether an individual is a "leased
employee", the determination of the Administrator shall be binding for all
purposes of the Plan notwithstanding any later recharacterization or
redetermination of such individual's status. (See footnote 1 below.)

         2.13. Employee. "Employee" means any individual employed by the
Employer, including leased employees (within the meaning of Code (S) 414(n)(2))
to the extent required under the Code and applicable regulations. Eligible
Employees with Credited Compensation in excess of the Code Section 401(a)(17)
limit shall have their Credited Compensation limited on a per pay period basis
to comply with such limit for Plan purposes.

         2.14. Employee After-Tax Contribution.  "Employee After-Tax
Contribution" means a contribution by a Participant under Section 5.5.

         2.15. Employer.  "Employer" means the Company and all Affiliated
Employers.

         2.16. Employment Commencement Date. "Employment Commencement Date"
means the date on which the Employee first performs an Hour of Service.




-----------------------
1   Effective April 30, 2000, certain Participants employed by the GTE
    Technology Organization cease to be Eligible Employees.


                                      -7-
<PAGE>

         2.17. ERISA.  "ERISA" means the Employee Retirement Income Security
Act of 1974, as from time to time amended.

         2.18. 401(k) Credited Compensation. "401(k) Credited Compensation"
means Credited Compensation determined without regard to non-sales-related
bonuses.

         2.19. Hours of Service. "Hours of Service" means, with respect to any
Employee, each hour for which the Employee is paid or entitled to payment from
the Employer.

         2.20. Investment Fund.  "Investment Fund" means one of the funds
established or designated from time to time by the Trustees to serve as
permissible investment vehicles for contributions made by or for the benefit of
a Participant, including any such fund maintained under the Prior Plan for
participants thereunder and continued under the Plan. Funds may consist in whole
or in part of investments in shares of a regulated investment company or such
other investments as the Trustees, in their sole discretion, deem appropriate.
Loans to Participants (made in accordance with Article 12) hereof shall be
permissible investment of each Investment Fund other than the Trustees' Fund.
The Trustees may terminate an Investment Fund as to existing or future
investments or both and may designate new or different Investment Funds at any
time. Matching Contributions made in shares of common stock of Genuity Inc.
shall be held in the Trust in a fund consisting of such stock (plus, if the
Trustees so determine, cash or short-term liquid investments such as money-
market fund shares). Any such fund may be accounted for on a share basis or a
unitized basis, as the Administrator determines.

         2.21. Matching Contribution.  "Matching Contribution" means a
Participating Employer's contribution made pursuant to Section 5.4 in full or
partial matching of (i.e., on

                                      -8-
<PAGE>

account of) Pre-Tax Contributions made by the Participating Employer. The term
"basic Matching Contributions" refers to Matching Contributions made in
accordance with a percentage rate of contribution fixed by a Participating
Employer before the beginning of a Plan Year, and the term "supplemental
Matching Contributions" refers to discretionary Matching Contributions
determined by the Participating Employer after such time.

         2.22. Participant.  "Participant" means any Eligible Employee who
participates in the Plan in accordance with Article 4 hereof. A Participant who
has ceased to be eligible to make or share in contributions under the Plan, but
who continues to have an accrued benefit under the Plan, shall be referred to as
a "former Participant".

         2.23. Participating Employer.  "Participating Employer" means (i) the
Company and (ii) any Affiliated Employer which has adopted the Plan with the
approval of the Company.

         2.24.  Plan.  "Plan" means the Genuity Savings Plan as set forth in
this Agreement, and as amended from time to time.

         2.25.  Plan Year.  "Plan Year" means the six-month period beginning
July 1, 1999 and ending December 31, 2000 and each calendar year thereafter. For
purposes of Code (S) 415 and Section 8.3, (a) effective January 1, 2000 the
limitation year will be the calendar year, and (b) the period July 1, 1999
through December 31, 1999 shall be a "limitation period" as that term is defined
in Treas. Regs. (S) 1.415-2(b)(4); provided, that in applying the provisions of
Code (S) 415 and Section 8.3 to such July 1, 1999 to December 31, 1999
limitation period the dollar limit described in Code (S) 415(c)(1)(A) and
Section 8.3(a)(i) shall be $15,000 and only compensation for the limitation
period shall be taken into account.

                                      -9-
<PAGE>

         2.26. Pre-Tax Contribution.  "Pre-Tax Contribution" means a
contribution made to the Plan for the benefit of a Participant pursuant to a
salary reduction agreement described in Sections 5.2 and 5.3.

         2.27. Primary Contribution.  "Primary Contribution" means a
discretionary contribution by a Participating Employer under Section 5.1.

         2.28. Prior Plan.  "Prior Plan" means the Bolt Beranek and Newman Inc.
Retirement Trust Agreement, as amended and in effect from time to time prior to
the Effective Date.

         2.29. Qualified Domestic Relations Order.  "Qualified Domestic
Relations Order" or "QDRO" means any judgment, decree or order (including
approval of a property settlement agreement) which:

               (a)  relates to the provision of child support, alimony payments,
     or marital property rights to a spouse, former spouse, child or other
     dependent of a Participant or former Participant;

               (b)  is made pursuant to a State domestic relations law
     (including a community property law); and

               (c)  constitutes a "qualified domestic relations order" within
     the meaning of Code (S) 414(p) and ERISA Section 206(d)(3)(B).

A domestic relations order will not fail to qualify as a QDRO merely because it
calls for distributions at a time when the Participant would not himself be
eligible for a distribution, including any such time prior to the Participant's
"earliest retirement age" as that term is defined in Section 414(p)(4)(B) of the
Code.

                                      -10-
<PAGE>

         2.30. Rollover Contribution.  "Rollover Contribution" means (i) a
contribution or direct transfer to the Trust described in Section 402(c) of the
Code from another plan qualified under Section 401(a) of the Code, or (ii) to
the extent permitted by the Administrator, a contribution to the Trust of an
amount distributed from an individual retirement account or annuity and
described in Section 408(d)(3)(A)(ii) of the Code.

         2.31.  Service.  "Service" means, in the case of any Employee, the
period of time, expressed in years and fractions of years measured in days, that
begins with the Employee's employment date or reemployment date and ends on the
earlier of (a) the date the Employee quits, retires, is discharged or dies, or
(b) the first anniversary of the Employee's absence from service for any other
reason. If the reemployment date of an Employee who is absent from service (for
any reason, including by reason of a quit, retirement or discharge) falls within
twelve (12) months after the commencement of such absence, the intervening
period of absence shall be treated as a period of Service. If an Employee's
reemployment date occurs more than twelve (12) months after the commencement of
the absence, the period commencing with the reemployment date shall be treated
as a new period of Service under the rules described above and shall be
aggregated with any prior periods of Service. For purposes of this Section 2.31,
"employment date" means the date on which an Employee first has an Hour of
Service, "reemployment date" means the date on which an Employee has an Hour of
Service after the commencement of an absence, and the terms "service", "absence
from service", "quit", "retirement", "discharge" and related terms shall all be
applied by reference to employment for the Employer; provided, that the Board of
Directors may provide by appropriate action, in such

                                      -11-
<PAGE>

cases and subject to such exceptions and rules as it may determine, that service
for a corporation, trade or business prior to its becoming an Affiliated
Employer shall also be treated as Service.

         2.32. Share of the Trust Fund.  "Share of the Trust Fund" means, in the
case of any Participant or former Participant, that portion of the Trust's
assets which is allocated to the Accounts of the Participant or former
Participant.

         2.33. Stock.  "Stock" means common stock of the Company. Stock may be
acquired by the Trustees for investment in the Trust Fund either by open market
purchases or in negotiated transactions, including purchases from the Company.

         2.34. Termination of Employment Date. "Termination of Employment Date"
means the day on which a Participant ceases to be an Employee, as determined by
the Company.

         2.35. Trust.  "Trust" means the BBN Corporation Retirement Trust
heretofore established and continued under this Agreement, as amended and in
effect from time to time.

         2.36. Trust Fund.  "Trust Fund" means the property held in trust by the
Trustees for the account of Participants, former Participants and their
Beneficiaries.

         2.37. Trustees.  "Trustees" means those person(s) who are appointed by
the Board of Directors from time to time to act as Trustees hereunder.

         2.38. Trustees' Fund.  "Trustees' Fund" means the frozen Investment
Fund established under the Prior Plan and continued hereunder, the assets of
which are allocated for investment purposes to certain Participants and former
Participants with accounts under the Prior Plan as of January 1, 1984. The
Trustees' Fund is not open for additional investment except for the investment
or reinvestment of cash held therein, and is therefore not among the Investment

                                      -12-
<PAGE>

Funds available for Participant-directed investments under Article 6. The
Trustees may at any time and from time to time withdraw some portion or all of
the assets in the Trustees' Fund and reinvest them in one or more of the other
Investment Funds maintained under the Plan.

     Whenever used herein, a pronoun or adjective in the masculine gender
includes the feminine gender unless the context clearly indicates otherwise.

                                      -13-
<PAGE>

Article  3.   Administration.
              --------------

         3.1. Administrator.  The Plan will be administered by the
Administrator, which will be a committee consisting of at least three
individuals (who may but need not be Participants or former Participants)
appointed from time to time by the Board of Directors and subject to removal by
the Board of Directors at any time, with or without cause.

     The committee appointed to serve as Administrator will act by vote of a
majority of all its members.  If at any time a majority of the individuals
serving on such committee and eligible to vote are unable to agree, or if there
is only one such individual, any action required of the committee will be taken
by the Board of Directors and its decision will be final.  An individual serving
on such committee who is a Participant or former Participant may not vote or act
on any matter relating solely to himself.  Members of the Administrator shall
serve without remuneration (other than reimbursement for reasonable expenses)
except as may otherwise from time to time be agreed upon by the Company and the
Administrator consistent with ERISA.

     Notwithstanding any other provisions of the Plan, the Administrator will
have the full power and discretion to conform the administration of the Plan
with the administration of the GTE Savings Plan.

         3.2.  Powers and discretionary authority.  The Administrator will have
full power and discretion to administer the Plan in all of its details and to
determine all matters relating thereto, subject, however, to the requirements of
ERISA. The Administrator's determinations shall be final and binding on all
Employees, former Employees, Participants, former Participants, and

                                      -14-
<PAGE>

Beneficiaries. More particularly, but not in limitation of the foregoing, the
Administrator shall have the following discretionary authority:

         (a)   To make and enforce such rules and regulations as it deems
     necessary or proper for the efficient administration of the Plan;

         (b)   To interpret the Plan, its interpretation thereof in good faith
     to be final and conclusive on all Employees, former Employees,
     Participants, former Participants, and Beneficiaries;

         (c)   To decide all questions concerning the Plan and the eligibility
     of any person to participate in the Plan in accordance with Article 4;

         (d)   To compute the amount of benefits which will be payable to any
     Participant, former Participant or Beneficiary in accordance with the
     provisions of the Plan, and to determine the person or persons to whom such
     benefits will be paid;

         (e)   To authorize the payment of benefits;

         (f)   To grant loans to Participants in accordance with Section 12.3
     herein;

         (g)   To appoint such agents, counsel, accountants, consultants and
     actuaries as may be required to assist in administering the Plan; and

         (h)   By written instrument, to allocate and delegate fiduciary
     responsibilities in accordance with Section 405 of ERISA.

         3.3.  Examination of records.  The Administrator will make available to
each Participant or former Participant such of its records as pertain to him,
for examination at reasonable times during normal business hours.

                                      -15-
<PAGE>

         3.4.  Nondiscriminatory exercise of authority.  Whenever, in the
administration of the Plan, any discretionary action by the Administrator is
required, the Administrator shall exercise its authority in a nondiscriminatory
manner so that all persons similarly situated will receive substantially the
same treatment.

         3.5.  Reliance on tables, etc.  In administering the Plan, the
Administrator will be entitled to the extent permitted by law to rely
conclusively on all tables, valuations, certificates, opinions and reports which
are furnished by any actuary, accountant, trustee, counsel or other expert who
is employed or engaged by the Administrator.

         3.6.  Named fiduciary.  The Administrator will be a "named fiduciary"
for purposes of Section 402(a)(1) of ERISA with authority to control and manage
the operation and administration of the Plan, except that the Administrator will
have no authority over the investment of the assets of the Trust.

         3.7.  Expenses of Plan.  Unless paid by a Participating Employer, the
Administrator will direct the Trustees to pay from the Trust Fund the expenses
incurred by the Administrator in administering the Plan to the extent such
expenses are reasonable. Any such direction will be in writing and will specify
the amount to be paid and the person to whom payment is to be made. The
Administrator will determine what constitutes a reasonable expense of
administering the Plan, which determination in good faith will be final and
conclusive on all persons having any interest in the Plan.

                                      -16-
<PAGE>

         3.8.  Claims and review procedures.

               (a)  Claims procedure.  If any person believes he is being denied
     any rights or benefits under the Plan, such person may file a claim in
     writing with the Administrator. If any such claim is wholly or partially
     denied, the Administrator will notify such person of its decision in
     writing. Such notification will contain (i) specific reasons for the
     denial, (ii) specific reference to pertinent Plan provisions, (iii) a
     description of any additional material or information necessary for such
     person to perfect such claim and an explanation of why such material or
     information is necessary and (iv) information as to the steps to be taken
     if the person wishes to submit a request for review. Such notification will
     be given within ninety (90) days after the claim is received by the
     Administrator (or within one hundred eighty (180) days, if special
     circumstances require an extension of time for processing the claim, and if
     written notice of such extension and circumstances is given to such person
     within the initial ninety (90) day period). If such notification is not
     given within such period, the claim will be considered denied as of the
     last day of such period and such person may request a review of his claim.

               (b)  Review procedure.  Within sixty (60) days after the date on
     which a person receives a written notice of a denied claim (or if
     applicable, within sixty (60) days after the date on which such denial is
     considered to have occurred) such person (or his duly authorized
     representative) may (i) file a written request with the Administrator for a
     review of his denied claim and of pertinent documents and (ii) submit
     written issues and comments to the Administrator. The Administrator will
     notify such person of its decision

                                      -17-
<PAGE>

     in writing. Such notification will be written in a manner calculated to be
     understood by such person and will contain specific reasons for the
     decision as well as specific references to pertinent Plan provisions. The
     decision on review will be made within sixty (60) days after the request
     for review is received by the Administrator (or within one hundred twenty
     (120) days, if special circumstances required an extension of time for
     processing the request, such as an election by the Administrator to hold a
     hearing, and if written notice of such extension and circumstances is given
     to such person within the initial sixty (60) day period). If the decision
     on review is not made within such period, the claim will be considered
     denied.

         3.9.  Indemnification of Administrator.  The Company agrees to
indemnify and to defend to the fullest extent permitted by law an Employee or
former Employee serving or formerly serving as the Administrator or as a member
of a committee appointed to serve as Administrator against all liabilities,
damages, costs and expenses (including attorneys' fees and amounts paid in
settlement of any claims approved by the Company) occasioned by any act or
omission to act in connection with the Plan, if such act or omission was in good
faith.

                                      -18-
<PAGE>

Article  4.    Participation.
               -------------

         4.1.  Date of participation.  Each individual shall become a
Participant for all purposes of the Plan on whichever of the following two days
(the "entry date") first occurs:

                    (i)  the first day of the month (i.e., January 1, February
               1, etc.) that follows by at least one month the date on which the
               individual becomes an Eligible Employee, or

                    (ii) the January 1 or July 1 which first occurs following
               completion of a year of Service;

provided, that if the individual is not an Eligible Employee on such entry date,
he or she shall become a Participant on the first date thereafter on which he or
she is an Eligible Employee; and further provided, that in determining an
individual's right to participate in the Plan as of any date prior to January 1,
1999, the provisions of Section 4.1 as from time to time in effect prior to
January 1, 1999 shall control rather than the provisions set forth above.

         4.2.  Cessation of participation.  A Participant will cease to be a
Participant and will become a former Participant as of the date on which he
ceases to be an Eligible Employee or, if earlier, as of the date on which the
Plan terminates.

         4.3.  Reemployment of a former Participant.  If a former Participant
returns to the employ of a Participating Employer, no distributions (other than
withdrawals pursuant to Article 12, mandatory distributions pursuant to Section
13.3 upon attainment of age 70 1/2, or corrective distributions under Section
8.3 or Appendix I) will be made to him while he continues to be an

                                      -19-
<PAGE>

Eligible Employee. A former Participant will again become a Participant on the
date on which he completes an Hour of Service following his reemployment.

                                      -20-
<PAGE>

Article  5.    Contributions.
               -------------

         5.1.  Primary Contributions.  Each Participating Employer will
contribute to the Trust for each Allocation Period during the continuance of the
Plan a Primary Contribution in such amount (if any) as may be determined by the
Board of Directors with respect to such Allocation Period. The amount of each
such contribution, whether expressed as an aggregate amount or as a percentage
of Credited Compensation for the Allocation Period, may vary among different
Participating Employers. In addition, the Board of Directors may identify for
purposes of this Section for any Allocation Period separate business units,
segments or divisions (a "separate unit" or "unit") within a Participating
Employer and provide that a different amount or different percentage of Credited
Compensation (including, if so determined, a zero contribution) will be
contributed with respect to one or more such separate units while a different
amount or amounts or a different percentage rate or rates will be contributed
for other units. The identification of separate units, if any, within a
Participating Employer shall be made before the end of the Allocation Period to
which the Primary Contribution relates. Unless the Board of Directors
affirmatively designated separate units for purposes of this Section for an
Allocation Period, contributions by a Participating Employer for such Allocation
Period shall be allocated and apportioned among the eligible Participants of
such Participating Employer as though it were a single unit. In making
determinations under this Section, the Board of Directors may, but need not,
take into account the relative profitability of different Participating
Employers or different units or such other business factors as it may determine.

                                      -21-
<PAGE>

         5.2.  Pre-Tax Contributions.  Each Participant may enter into a salary
reduction agreement with his Participating Employer specifying Pre-Tax
Contributions in an amount designated in the agreement. By agreeing to Pre-Tax
Contributions, the Participant agrees to a reduction in 401(k) Credited
Compensation in the amount or percentage designated and the Participating
Employer agrees in consideration of such reduction to contribute an equivalent
amount to the Trust. The Administrator may establish and from time to time
modify limits on the amount or percentage of 401(k) Credited Compensation which
may be elected to be contributed to the Plan, and such limits may be different
for different classifications of Participants.

         5.3.  Form and manner of Pre-Tax Contribution elections.  Each salary
reduction agreement shall be on a form prescribed or approved by the
Administrator and may be entered into, changed or revoked by the Participant,
upon such prior written notice as the Administrator may prescribe, as of the
first day of any Allocation Period or on such other basis as the Administrator
may determine. A salary reduction agreement shall be effective with respect to
401(k) Credited Compensation payable on and after the date specified in the
Agreement but no earlier than the date the agreement is entered into.

         5.4.  Matching Contributions.  The Board of Directors shall determine
and shall communicate or cause to be communicated to Participants the rate
(which may be zero) of basic Matching Contributions that will apply under the
Plan; provided, that except as otherwise determined by the Board of Directors,
and subject to the valuation provisions of the last paragraph of this Section
and to limitation as elsewhere provided in the Plan, the rate of basic

                                      -22-
<PAGE>

Matching Contributions with respect to any Participant shall be seventy-five
cents ($0.75) for each one dollar ($1.00) of "match-eligible" contributions (as
hereinafter defined) made by or for the benefit of the Participant. For purposes
of this Section, the term "match-eligible" contributions for any period means,
except as otherwise determined by the Board of Directors, the aggregate of the
Pre-Tax Contributions made for the benefit of, and the Employee After-Tax
Contributions made by, a Participant for such period to the extent such
contributions do not exceed six percent (6%) of the Participant's 401(k)
Credited Compensation for such period. Basic Matching Contributions, if any,
determined in accordance with this paragraph shall be made to the Trust by each
Participating Employer for the benefit of each Participant it employs during the
Plan Year who made match-eligible Employee After-Tax Contributions with respect
to such period of employment or for whose benefit the Participating Employer
made match-eligible Pre-Tax Contributions.

     In addition to basic Matching Contributions, if any, determined in
accordance with the preceding paragraph, each Participating Employer may make
supplemental Matching Contributions in such amounts, at such rates and subject
to such conditions as the Board of Directors may determine.

     Except as otherwise determined by the Board of Directors, all Matching
Contributions under the Plan shall be made in the form of shares of common stock
of Genuity Inc.  Genuity Inc. shall make such arrangements as it deems
appropriate to provide for such contributions on behalf of the Participating
Employers.  In determining the number of shares of such common stock of Genuity
Inc. required to be contributed as a Matching Contribution for any period, such

                                      -23-
<PAGE>

shares shall be valued in accordance with such reasonable and consistent
procedures as the Administrator may determine.

         5.5.  Employee After-Tax Contributions.  Any Participant may, at his
option, contribute to the Trust in any Plan Year a portion of his 401(k)
Credited Compensation. Employee After-Tax Contributions shall be made through
authorized payroll deductions or at such other time or times and in such manner
as the Administrator may determine. A Participant may discontinue his Employee
After-Tax Contributions at any time, but in the case of any such contributions
made by payroll deduction may not otherwise change the amount of such deductions
more frequently than would be permitted for changes in salary reduction
agreements under Section 5.3 above.

     If a Participant's Pre-Tax Contributions reach the limit set forth in
Section 402(g) of the Code during a Plan Year, any additional contributions made
pursuant to the Participant's salary reduction agreement during that Plan Year
shall automatically be made as Employee After-Tax Contributions, except to the
extent that such contributions would cause the Plan to exceed (or further to
exceed) the contribution percentage limit imposed by Code Section 401(m) or the
aggregate limit imposed by Treasury Regulation Section 1.401(m)-2 for the Plan
Year.

         5.6.  Rollover Contributions.  An Eligible Employee (who may be, but
need not be, a Participant) may make a Rollover Contribution to the Plan upon
demonstration to the Administrator that the contribution is an eligible Rollover
Contribution as defined in Section 2.33. The Administrator may require such
certificates or other evidence as it determines

                                      -24-
<PAGE>

to be necessary or appropriate to demonstrate that an amount is eligible to be
contributed or transferred to the Plan under this Section.

         5.7.  Other transfers.  The Board of Directors in its discretion may
provide that the Trust will accept a direct transfer, qualifying under Code (S)
414(l), of assets and liabilities from another plan and trust qualifying under
Code (S) 401(a). Any such transfer shall be made only after the transferring
plan or its sponsor or administrator has provided the Administrator with
evidence satisfactory to the Administrator as to the qualification of the
transferor plan and as to any and all benefit forms and options that would be
required under Code (S) 401(a)(11) or (S) 411 to be preserved with respect to
the transferred benefits.

         5.8.  Time for making contributions.  Pre-Tax Contributions and
Employee After-Tax Contributions made on a payroll deduction basis will be paid
in cash to the Trust as soon as they can reasonably be segregated from the
general assets of the Participating Employer, but in all events by the fifteenth
(15th) business day of the month following the month in which the compensation
to which such contributions relate would have been payable to the Participant in
cash. Employee After-Tax Contributions made directly by a Participant will be
deposited directly into the Trust. Primary Contributions, if any, for a Plan
Year will be contributed in cash to the Trust no later than the time prescribed
by law (including extensions) for filing the Participating Employer's federal
income tax return for its taxable year in or with which the Plan Year ends. A
Participating Employer's basic Matching Contributions, if any, shall be made
substantially at the same time as the related Pre-Tax Contributions, and its
supplemental

                                      -25-
<PAGE>

Matching Contributions, if any, shall be made at such time as the Participating
Employer determines (not later than the time for making a Primary Contribution
for the Plan Year).

         5.9.  Certain limits apply.  All contributions to the Plan are subject
to the applicable limits described or referred to in Article 8.

         5.10. Return of contributions.  If any contribution by a Participating
Employer to the Trust is

         (a)   made by reason of a good faith mistake of fact, or

         (b)   believed by the Participating Employer in good faith to be
               deductible under Code (S) 404, but the deduction is disallowed,

the Trustees shall, upon request by the Participating Employer, return to the
Participating Employer the excess of the amount contributed over the amount, if
any, that would have been contributed had there not occurred a mistake of fact
or a mistake in determining the deduction.  Such excess shall be reduced by the
losses of the Trust attributable thereto, if and to the extent such losses
exceed the gains and income attributable thereto.  In no event shall the return
of a contribution hereunder cause any Participant's Accounts to be reduced to
less than they would have been had the mistaken or nondeductible amount not been
contributed.  No return of a contribution hereunder shall be made more than one
year after the mistaken payment of the contribution, or disallowance of the
deduction, as the case may be.

                                      -26-
<PAGE>

Article  6.    Investments.
               -----------

         6.1.  Investment of contributions.  The Trustees shall maintain one or
more Investment Funds for the investment of contributions made by or for the
benefit of Participants. Subject to Section 6.4 and to such reasonable
procedures, restrictions and limitations as the Trustees may establish,
contributions by or for the benefit of a Participant, other than assets
allocated to the Trustees' fund, will be invested in such Investment Fund or
Funds as the Participant directs. Assets of the Trustees' Fund will be invested
solely by the Trustees or by an investment manager appointed pursuant to Section
16.2(t).

     It is intended that the Investment Funds provided under the Plan (other
than the Trustees' Fund and the fund consisting of common stock (and such cash
or other short-term investments as the Trustees may determine) attributable to
Matching Contributions) and manner of selection among such Funds shall satisfy
ERISA Section 404(c).  The Trustees will communicate to Participants and
Beneficiaries the investment options available under the Plan, including changes
in available investment options.  The Trustees may change the Investment Funds
offered under the Plan at any time, including with respect to already invested
amounts, and may terminate an Investment Fund at any time and transfer the
assets of a terminated Fund to any other Investment Fund.

         6.2.  Investment of income.  Dividends, interest and other income from
investments for the Account of any Participant shall be reinvested in the
Investment Fund or Funds to which such dividends, interest or other income is
attributable, subject to such reasonable restrictions or limitations as the
Trustees may establish.

                                      -27-
<PAGE>

         6.3.  Change of election by Participant.  A Participant may from time
to time change the Investment Funds in which contributions made by him or for
his benefit, or existing balances (other than any portion of the Participant's
share of the Trust Fund which is allocated to the Trustees' Funds), or both, are
to be invested, subject to such reasonable restrictions or limitations as the
Trustees may prescribe. Changes relating to future contributions will be
effective as soon as practicable after the change notice is given or, if later,
as of the date specified in the change notice. Changes relating to existing
Account balances, requiring liquidation of investments and reinvestment of the
proceeds, will be made as soon as reasonably practicable after the change notice
is given. The Trustees shall prescribe rules governing the periods and manner in
which investment changes may be made, including in the Trustees' discretion
rules permitting the giving of investment change notices by telephone or other
means, and nothing in this Section 6.3 shall prevent the Trustees from
prescribing rules with respect to former Participants that differ from the rules
prescribed for Participants. To the extent consistent with Code (S) 411(a)(11),
rules prescribed under this Section 6.3 with respect to former Participants may
include a rule suspending, eliminating or restricting the right of former
Participants to change investment elections.

         6.4.  Investment Fund for certain Matching Contributions.  As provided
in Section 2.20, Matching Contributions made in shares of common stock of
Genuity Inc. shall be held in the Trust in a fund consisting of such stock
(plus, if the Trustees so determine, cash or short-term liquid investments such
as money-market fund shares). Except as determined by the Administrator
consistent with an effective registration statement or exemption under the

                                      -28-
<PAGE>

Securities Act of 1933, as amended, and applicable state laws, no amounts
allocated to other Investment Funds under the Plan may be directed by a
Participant, former Participant or beneficiary to be invested in such Genuity
stock fund, nor shall any amounts invested in such fund be eligible to be
transferred by Participant, former Participant or beneficiary direction to any
other Investment Fund.

                                      -29-
<PAGE>

Article  7.    Participants' Accounts.
               ----------------------

         7.1.  Individual accounts.  The Trustees shall establish and maintain
Accounts for each Participant which shall reflect (i) all contributions paid to
the Trustees by or on behalf of the Participant, (ii) the Participant's share of
any forfeitures arising under the Plan, and (iii) the Participant's share of the
income, expenses, and gain or loss (realized or unrealized) of the Trust Fund.

         7.2.  Crediting of contributions.  Pre-Tax Contributions, Employee
After-Tax Contributions and basic Matching Contributions, if any, for the
benefit of a Participant shall be credited to the corresponding Accounts of the
Participant as of the date the amounts are contributed to the Trust. Subject to
Section 7.5, supplemental Matching Contributions and Primary Contributions, if
any, for the benefit of a Participant shall be credited to the Participant's
corresponding Accounts as of the last day of the Plan Year for which the
contribution is made. Rollover Contributions and amounts transferred in a trust-
to-trust transfer under Section 5.7 shall be credited to Accounts as of the
effective date of contribution or transfer.

         7.3.  Treatment of forfeitures.  If a Participant forfeits an interest
in his Primary Contribution Account pursuant to Section 11.4 below, the
forfeited amount will be transferred to a forfeiture account. The balance in the
forfeiture account as of the last business day of the Plan Year, after the
adjustments then to be made under Section 7.4, will be first used to restore
amounts previously forfeited under Section 11.4 to the accounts of Participants
entitled to such a restoration pursuant to Section 11.4, and then will be
allocated among and credited to the accounts of Participants or former
Participants who either (i) are employed by the Employer on

                                      -30-
<PAGE>

the last business day of the Plan Year and who have completed 1000 or more Hours
of Service during the Plan Year or (ii) ceased to be employed by a Participating
Employer during the Plan Year because they ceased to be Employees and who had a
one hundred (100) percent vested interest in their Primary Contribution Account,
in proportion to the respective amount of Credited Compensation paid to such
individuals (while they were Participants) by the Participating Employers during
such Plan Year.

         7.4.  Adjustments to individual accounts.  At such times as the
Trustees shall determine, but no less frequently than once each Allocation
Period (except in the case of forfeitures, which shall be applied once at the
end of the Plan Year), the Trustees will cause the interest of each
Participant's Account (and any forfeiture account) in each Investment Fund to be
adjusted to include its allocable share of the income and of the gain and loss
(realized and unrealized) on the assets of such Investment Fund valued at their
fair market value (except that the amounts allocated under this Section 7.4 will
not include any income or gain or loss on assets attributable to Primary
Contributions or supplemental Matching Contributions for the year with respect
to which the allocation is made). From time to time but not less frequently than
annually, the balance in each Account may be similarly adjusted, to the extent
necessary, to reflect its proper share of those expenses of the Trustees and the
Administrator which are to be charged to the Trust Fund.

         7.5.  Eligibility to share in Primary Contributions and supplemental
Matching Contributions. The Primary Contributions, if any, contributed by a
Participating Employer for an Allocation Period with respect to each of its
separate units (as determined in accordance with

                                      -31-
<PAGE>

Section 5.1) shall be allocated among and credited to the Primary Contribution
Accounts of Participants employed by or at such separate unit who

               (a)  are Eligible Employees on the last day of the Allocation
     Period, or

               (b)  who ceased to be Eligible Employees during the Allocation
     Period and who

had a one hundred (100%) vested interest in their Primary Contribution Account
in proportion to the respective amounts of Credited Compensation paid such
Participants during the Allocation Period.  If different levels of Primary
Contributions are contributed with respect to different units, the provisions of
the preceding sentence shall be applied separately to each such unit, with only
those Participants providing services to such unit (and only their Credited
Compensation with respect to such service) taken into account.  If the
Participating Employer has not designated separate units for an Allocation
Period, the Primary Contribution of the Participating Employer for such
Allocation Period will be allocated among and credited to the Primary
Contribution Accounts of Participants employed by the Participating Employer, in
accordance with the preceding sentence, as though the Participating Employer
consisted of a single unit.

     Supplemental Matching Contributions, if any, contributed by a Participating
Employer for a Plan Year shall be credited, similarly, only in respect of those
Participants otherwise eligible for the Matching Contribution (i.e., for whose
benefit Pre-Tax Contributions have been made) who satisfy the requirements of
(a) or (b) above; provided, that supplemental Matching Contributions described
in the last sentence of Section 5.4 shall be credited only in respect of

                                      -32-
<PAGE>

those otherwise eligible Participants who are Eligible Employees on the last day
of the Plan Year.

         7.6.  Rights of Participants.  Nothing contained herein shall be deemed
to give any Participant any interest in any specific part of the Trust Fund or
any interest other than his right to receive benefits in accordance with the
provisions herein contained.

                                      -33-
<PAGE>

Article  8.    Limits on Contributions.
               -----------------------

         8.1.  Deductibility of Contributions.  Primary Contributions, Pre-Tax
Contributions, and Matching Contributions (both basic and supplemental) for any
Plan Year shall not exceed the maximum amount deductible under the applicable
provisions of the Code and are hereby expressly conditioned on their
deductibility.

         8.2.  Nondiscrimination limitations.  Pre-Tax Contributions, Employee
After-Tax Contributions, and Matching Contributions (both basic and
supplemental) must also satisfy certain nondiscrimination requirements that are
set out in Appendix I and in connection with satisfying these requirements may
be prospectively reduced or in certain circumstances distributed to Participants
(or former Participants), all as more fully set out in Appendix I.

         8.3.  Limit on Annual Additions.  Primary Contributions, Pre-Tax
Contributions, Employee After-Tax Contributions and Matching Contributions (both
basic and supplemental) are subject also to the limitations under Code (S) 415,
which are incorporated herein by reference. In applying such limitations, the
limitation year or limitation period shall be the year or period described in
Section 2.25 ("Plan Year"), and the compensation taken into account for any
Participant shall be the Participant's wages (within the meaning of Code (S)
3401(a)) subject to income tax withholding at the source, determined without
regard to any rules that limit the remuneration included in wages based on the
nature or location of the employment or the services performed and increased by
amounts that would have been included in the Participant's wages as so defined
but for a deferral election described in Code (S) 125 or Code (S) 401(k). If the
Administrator determines that contributions by or for the benefit of a
Participant may give rise to

                                      -34-
<PAGE>

annual additions in excess of those permitted under Code (S) 415, it may
prospectively limit contributions or allocations of forfeitures to the extent
necessary to avoid such excess. If, notwithstanding the foregoing, the
Administrator determines that the amount credited to a Participant's account for
the preceding limitation year or limitation period exceeded the amount permitted
under Code (S) 415, the Administrator may take the following steps to the extent
necessary to correct such excess: (i) first, return to the Participant his or
her Employee After-Tax Contributions, together with associated earnings; (ii)
second, return to the Participant unmatched Pre-Tax Contributions made for his
or her benefit, together with associated earnings; (iii) third, return to the
Participant other Pre-Tax Contributions made for his or her benefit, together,
with associated Matching Contributions and earnings; and (iv) if the foregoing
steps do not suffice, reallocate to the Accounts of other eligible Participants
(subject to Section 7.5 and limitations of this Section) forfeitures and Primary
Contributions made for the benefit of the Participant for whom an excess annual
addition exists.

                                      -35-
<PAGE>

Article  9.    Benefits Because of Age or Disability.
               -------------------------------------

         9.1.  Normal retirement.  Upon attainment of age sixty-five (65) while
an Employee, each Participant will have a fully vested and nonforfeitable
interest in his Share of the Trust Fund. Upon retirement on or after age sixty-
five (65), the Participant's Share of the Trust Fund, including any amounts
attributable to contributions or forfeitures for the Plan Year in which he
retires, will be distributed to him in accordance with Article 13.

         9.2.  Disability retirement.  If a Participant becomes disabled prior
to attainment of age sixty-five (65) and if the disability is such that the
Participant can no longer continue in the service of the Participating
Employers, as determined by his Participating Employer under rules of uniform
application, and if his employment with the Participating Employer is terminated
(a "disability retirement"), the Participant will have a fully vested and
nonforfeitable interest in his Share of the Trust Fund. In such event, his Share
of the Trust Fund, including any amounts attributable to contributions or
forfeitures for the Plan Year in which his employment terminates, will be
distributed to him in accordance with Article 13.

                                      -36-
<PAGE>

Article 10.    Benefits Because of Death.
               -------------------------

        10.1.  Distribution of benefits upon death.  If a Participant or former
Participant dies before the distribution of his Share of the Trust Fund has
commenced or before such distribution has been completed, his designated
Beneficiary shall be entitled to receive, in accordance with Article 13, the
amount or remaining amount of the decedent's Share of the Trust Fund, including
any amounts attributable to contributions or forfeitures for the Plan Year in
which death occurred.

        10.2.  Designation of Beneficiary.  A Participant may designate a
Beneficiary or change a prior designation of a Beneficiary by giving notice to
the Administrator on a form approved by the Administrator; provided, however,
that if a Participant was married at time of death, he shall be deemed to have
designated his surviving spouse as his sole Beneficiary unless

               (a)  his surviving spouse, witnessed by a Plan representative or
     notary public, on a written form approved by the Administrator consented to
     and acknowledged the effect of, the decedent's designation of the specific
     non-spouse Beneficiary or Beneficiaries (including any class of
     Beneficiaries or any contingent Beneficiaries) designated by the decedent;
     or

               (b)  it is established to the satisfaction of the Administrator
     that the consent required under (a) above may not be obtained because there
     is no spouse, because the spouse cannot be located, or because of such
     other circumstances as the Secretary of the Treasury may prescribe.

                                      -37-
<PAGE>

Any consent by a spouse described above, or the establishment that the consent
and acknowledgment cannot be obtained, shall be effective only with respect to
such spouse, but shall be irrevocable once made.

     The Administrator will file a copy of any Beneficiary designation form with
the Trustees or, if a Participant is deemed to have designated his surviving
spouse as sole Beneficiary, will so inform the Trustees.  If a Participant dies
without specifically designating a Beneficiary, his Beneficiary shall be deemed
to be his surviving spouse or, if none, his issue per stirpes.  If any of such
issue is a minor, the Trustees may deposit the minor's share in a savings
account to his credit in a savings bank or other financial institution.  If
there is no surviving issue, then the amount may be paid to the Participant's
executor or administrator or applied to the payment of his debts and funeral
expenses or paid to any relative, all as the Administrator shall determine.

                                      -38-
<PAGE>

Article 11.    Benefits Because of Separation from Service.
               -------------------------------------------

        11.1.  Separation from service.  Benefits under this Article 11 shall be
payable on account of a Participant's or former Participant's "separation from
service" within the meaning of Section 401(k)(2)(B)(i)(I) of the Code.

        11.2.  Termination benefit.  A Participant or former Participant who has
separated from the service of the Company and its Affiliated Employers shall be
entitled under this Section 11.2 to a benefit equal to the value of (a) his
Employee After-Tax Contribution Account, Pre-Tax Contribution Account, Matching
Contribution Account, Rollover Account (if any), Transfer Account (if any), plus
(b) that portion (if any) of his Primary Contribution Account attributable to
"qualified nonelective contributions" (see Appendix I) or "cash election"
contributions under the Prior Plan or the earnings thereon, plus (c) the
applicable percentage of the value of the remaining portion of his or her
Primary Contribution Account, determined on the basis of the Participant's or
former Participant's completed years of Service as follows: (See footnote 2
below.)


          Completed Years of Service    Applicable Percentage
          --------------------------    ---------------------

          less than one                           - 0 -
          one but less than two                    50%
          two or more                             100%

The benefit determined under this Section shall be distributed in accordance
with Article 13.

        11.3.  Election of former vesting schedule.  If the Plan is amended at
any time after the Effective Date and if such amendment directly or indirectly
affects the computation of the nonforfeitable percentage of a Participant's
rights to his Share of the Trust Fund, each Participant who has completed three
(3) years of Service as of the end of the election period described below




-----------------
2  Effective April 30, 2000, certain Participants employed by the GTE Technology
   Organization are fully vested in their Accounts (to the extent such Accounts
   are not otherwise fully vested).

                                      -39-
<PAGE>

and whose nonforfeitable percentage any time after the amendment could be less
than such percentage determined without regard to the amendment, may elect,
during such election period, to have the nonforfeitable percentage of his Share
of the Trust Fund determined without regard to the amendment. The election
period referred to in the preceding sentence will begin on the date the
amendment is adopted and will end on the latest of the following dates:

               (i)   the date which is sixty (60) days after the date on which
     the amendment is adopted;

               (ii)  the date which is sixty (60) days after the date on which
     the amendment becomes effective; or

               (iii) the date which is sixty (60) days after the date on which
the Participant is issued written notice of the amendment by the Administrator.

An election under this Section 11.3 may be made only by an individual who is a
Participant at the time the election is made and once made shall be irrevocable.
If any Employee is a Participant on the date an amendment changing the vesting
schedule hereunder is adopted or the date the amendment becomes effective,
whichever is later, the Participant's nonforfeitable percentage (determined as
of such date) to his Share of the Trust Fund shall be not less than his
percentage determined without regard to the amendment.

        11.4.  Forfeitures.  In the case of a Participant who ceases to be an
Employee for any reason other than death or normal or disability retirement, any
portion of the Participant's Primary Contribution Account (including any amounts
credited after he ceases to be an Employee) not vested under Section 11.2 will
be forfeited by him as of his Termination of

                                      -40-
<PAGE>

Employment Date. After adjustment pursuant to Section 7.4, the forfeiture will
be applied as provided in Section 7.3. Any Participant or former Participant who
forfeits any portion of his or her Primary Contribution Account and is later
reemployed by an Employer prior to having incurred a period of severance of at
least five (5) years shall have the forfeited portion reinstated to his or her
Primary Contribution Account in accordance with Section 7.3. If the amount of
other forfeitures in the year of reemployment is insufficient to reinstate the
Participant's Primary Contribution Account under Section 7.3, the additional
amount required for such reinstatement shall be taken from Participating
Employer contributions for such year, prior to any other allocations of the
contributions. For purposes of this Section 11.4, a "period of severance" is a
period commencing with the later of the dates described in clauses (a) and (b)
of Section 2.31 and ending on an Employee's reemployment date (as that term is
used in Section 2.31), except that in the case of an absence from work by reason
of any of the maternity- or paternity-related reasons described in Code (S)
411(6)(E), the date described in clause (b) of Section 2.31 shall, for purposes
of determining the commencement date of any related "period of severance" under
this Section, be deemed to be the second rather than the first anniversary of
the Employee's absence. In the case of a Participant or former Participant who
incurs a period of severance of at least five (5) years' duration, any
subsequent period of Service shall be disregarded in determining the
Participant's or former Participant's vested interest under Section 11.2(c) in
amounts, if any, credited to his or her Primary Contribution Account in respect
of Service prior to such period of severance.

                                      -41-
<PAGE>

        11.5.  Separate account.  This Section applies if a distribution has
been made to a Participant or former Participant at a time when he has a
nonforfeitable right to less than one hundred (100%) percent of his Share of the
Trust Fund. Amounts credited to the Participant's Primary Contribution Account
(other than any such amounts designated as "qualified nonelective contributions"
(see Appendix I) or attributable to a "cash election" under the Prior Plan, and
earnings thereon), to the extent remaining after such a distribution, shall be
maintained as a separate account for the purpose of determining the
Participant's or former Participant's vested interest therein at any later time
prior to forfeiture. At any relevant time the Participant's or former
Participant's nonforfeitable interest in the separate account will be equal to
P(AB+(RxD))-(RxD), where P is the nonforfeitable percentage at the relevant time
determined under Section 11.2(c); AB is the account balance of the separate
account at the relevant time; D is the amount of the distribution; and R is the
ratio of the account balance of the separate account at the relevant time to the
account balance of such account immediately after the distribution. If a former
Participant suffers a forfeiture and upon later reemployment is entitled to
restoration of the forfeited amount, his vested interest, following
reemployment, in his Primary Contribution Account (including any such restored
amount) shall equal P(AB+(RxD))-(RxD), where P is the nonforfeitable percentage
at the relevant time; AB is the Account balance at the relevant time; D is the
amount of any prior distribution; and R is the ratio of the Account balance at
the relevant time to the Account balance after the distribution.

                                      -42-
<PAGE>

Article 12.    Withdrawals; Hardship Distributions; Loans.
               ------------------------------------------

        12.1.  Withdrawal of Employee After-Tax Contributions.  Any Participant
or former Participant may at any time withdraw from his Share of the Trust Fund
a sum not in excess of the value at the date of withdrawal of his Employee
After-Tax Contribution Account (reduced by the amount of prior withdrawals);
provided, that the minimum amount which may be withdrawn under this Section
shall be $500 or the total value of the Employee After-Tax Contribution Account,
whichever is less. The amount of any such withdrawal shall be paid to the
Participant as soon as reasonably practicable following valuation of the
Accounts after the notice of the withdrawal is given to the Trustees.

        12.2.  Hardship withdrawals.

               (a)  Immediate and heavy financial need.  A Participant or former
     Participant may make a withdrawal from his Pre-Tax Contribution Account in
     the event of an immediate and heavy financial need arising from

                    (1)  expenses for medical care described in Code (S) 213(d)
          previously incurred by the Participant or former Participant, his
          spouse or any of his dependents (as defined in Code (S) 152) or
          necessary for these persons to obtain such medical care;

                    (2)  costs directly related to the purchase of a principal
          residence of the Participant or former Participant (excluding mortgage
          payments);

                                      -43-
<PAGE>

                    (3)  the payment of tuition and related educational fees for
          the next 12-months of post-secondary education for the Participant or
          former Participant, his spouse, children or dependents (as defined in
          Code (S) 152); or

                    (4)  payments necessary to prevent the eviction of the
          Participant or former Participant from his principal residence or
          foreclosure on the mortgage on that principal residence.

     The Administrator's determination of whether there is an immediate and
     heavy financial need as defined above shall be made solely on the basis of
     written evidence furnished by the Participant.  Such evidence must also
     indicate the amount of such need.  In no event may a Participant withdraw
     under this Section 12.2 any amount in excess of the lesser of (i) the
     actual Pre-Tax Contributions made for his benefit and not previously
     withdrawn (i.e., not including any earnings or any amounts treated as Pre-
     Tax Contributions by reason of having been designated as a "qualified
     nonelective contribution" or "qualified matching contribution" (see
     Appendix I)), or (ii) the Participant's Pre-Tax Contribution Account
     excluding any portion thereof invested in a note described in Section
     12.3(i) below.

               (b)  Distribution of amount necessary to meet need. As soon as
     practicable after the Administrator's determination that an immediate and
     heavy financial need exists with respect to a Participant or former
     Participant and that the Participant or former Participant has obtained all
     other distributions (other than hardship distributions) and all nontaxable
     loans currently available under the Plan and all other plans maintained by
     any Affiliated

                                      -44-
<PAGE>

     Employer, the Administrator will direct the Trustee to pay to the
     Participant or former Participant the amount necessary to meet the need
     created by the hardship (but not in excess of the amount available for such
     a distribution as determined under (a) above). The amount necessary to meet
     the need may include any amounts necessary to pay any federal, state, or
     local income taxes or penalties reasonably anticipated to result from the
     distribution.

               (c)  Effect of hardship withdrawal. If a Participant receives a
     hardship distribution under this Section, then Pre-Tax Contributions,
     Employee After-Tax Contributions and other cash-or-deferred or employee
     contributions by or for the benefit of the Participant under the Plan or
     any other plan of the Employer, whether or not tax qualified, shall be
     suspended for the 12-month period beginning with the date of the
     withdrawal; and the amount of Pre-Tax Contributions (together with elective
     deferrals under other plans, if any, of the Employer) for the calendar year
     immediately following the calendar year of the withdrawal must not exceed
     the limit described in Appendix I, Section I.3 as in effect for such next
     calendar year reduced by the amount of such contributions for the benefit
     of the Participant for the calendar year of the withdrawal.

        12.3.  Loans.
               -----

               (a)  In General.  Upon the written request of a Participant on a
     form approved or prescribed by the Administrator, and subject to the
     conditions of this Section, the Administrator shall direct the Trustee to
     make a loan from the Trust to such Participant. Former Participants and
     Beneficiaries of Participants or former Participants shall not be

                                      -45-
<PAGE>

     eligible to obtain loans under this Article, except to the extent required
     by applicable regulations issued by the Department of Labor or as otherwise
     provided at subsection (k) below; but a loan which is outstanding at the
     time a borrower ceases to be a Participant shall not, solely for that
     reason, be accelerated or otherwise become immediately due and payable.
     Except as otherwise determined by the Administrator, from and after the
     date of the initial public offering of Genuity Inc. no person may have
     outstanding at one time more than two loans from the Plan, provided, that
     this provision shall not be applied to require the prepayment of any loan
     outstanding at such date.

               (b)  Rules and procedures.  The Administrator shall promulgate
     such rules and procedures, not inconsistent with the express provisions of
     this Article, as it deems necessary to carry out the purposes of this
     Article. All such rules and procedures shall be deemed a part of the Plan
     for purposes of the Department of Labor's Regulation Section 2550.408b-
     1(d).

               (c)  Maximum amount of loan.  The following limitations shall
     apply in determining the amount of any loan to a Participant hereunder:

                    (1)  The amount of the loan, together with all loans (if
          any) outstanding under other qualified retirement plans of the
          Affiliated Employers, shall not exceed $50,000 reduced by the excess
          of (1) the highest outstanding loan balance of the Participant from
          such plans during the one-year period ending on the day prior to the
          date on which the loan is made, over (2) the Participant's outstanding
          loan balance from such plans immediately prior to the loan.

                                      -46-
<PAGE>

                    (2)  The amount of the loan shall not exceed fifty (50%)
          percent of the sum of (i) the Participant's Employee After-Tax
          Contribution Account, Pre-Tax Contribution Account, Matching
          Contribution Account and Rollover Account and Transfer Account where
          relevant, and (ii) the vested portion of the Participant's Primary
          Contribution Account, in each case determined as of the date the loan
          is made or, in the case of any Account or fund that cannot be valued
          as of that date, as of the most recent valuation date.

          (d)  Minimum amount of loan.  The minimum amount of any single loan
     under this Plan shall be $1000.

          (e)  Note; security; interest. Each loan shall be evidenced by a note
     signed by the Participant and shall be secured by not more than 50% of the
     Participant's nonforfeitable interest in his Share of the Trust Fund,
     including in such security the note evidencing the loan. The loan shall
     bear interest at an annual percentage interest rate to be determined by the
     Administrator. In determining the interest rate, the Administrator shall
     take into consideration interest rates currently being charged by persons
     in the business of lending money with respect to loans made in similar
     circumstances. The Administrator shall make such determination through
     consultation with one or more lending institutions, as the Administrator
     deems appropriate.

          (f)  Repayment. Each loan made to a Participant who is receiving
     regular payments of compensation from a Participating Employer shall be
     repayable by payroll deduction. Loans made to other Participants (and, in
     all events, where payroll deduction

                                      -47-
<PAGE>

     is no longer practicable) shall be repayable in such manner as the
     Administrator may from time to time determine. In each case payments shall
     be made not less frequently than quarterly, over a specified term (as
     determined by the Administrator) not to exceed five years, with
     substantially level amortization (as that term is used in Code (S)
     72(p)(2)(C)).

          (g)  Repayment upon distribution. If, at the time benefits are
     distributed to a Participant, former Participant or Beneficiary under
     Articles 9, 10 or 11, there remains any unpaid balance of a loan hereunder,
     such unpaid balance shall, to the extent consistent with Department of
     Labor regulations, become immediately due and payable in full. The unpaid
     balance, together with any accrued but unpaid interest on the loan, shall
     be deducted from the Participant's or former Participant's account, subject
     to the default provisions below, before any distribution of benefits is
     made.

          (h)  Default. In the event of a default in making any payment of
     principal or interest when due under the note evidencing any loan under
     this Section, if the default continues for more than 14 days after written
     notice of the default by the Trustees or Administrator, the unpaid
     principal balance of the note shall immediately become due and payable in
     full. The unpaid principal, together with any accrued but unpaid interest,
     shall be deducted from the Participant's or former Participant's Account
     and treated as distributed to the Participant or former Participant and
     applied by the Participant or former Participant as a payment of the unpaid
     interest and principal (in that order) under the note evidencing such loan.
     However, the Administrator shall not apply the

                                      -48-
<PAGE>

     Participant's or former Participant's account to satisfy the repayment
     obligation to the extent such application would constitute a distribution
     inconsistent with the Plan's continued tax qualification.

          (i)  Note as Trust asset. The note evidencing a loan to a Participant
     under this Article shall be an asset of the Trust which is allocated to the
     Accounts of such Participant in the order hereinafter determined. Payments
     of principal and interest on the note shall be credited to the Accounts of
     the Participant in proportion to the portions of the note balance allocated
     to each such Account. For purposes of the first sentence of this
     subsection, any note shall be allocated first to a Participant's Primary
     Contribution Account (to the extent of the vested balance of such Account
     determined as of the date the loan is made), with any balance allocated to
     the Participant's Matching Contribution Account, Rollover Account, Employee
     After-Tax Contribution Account, Transfer Account and Pre-Tax Contribution
     Account, in that order.

          (j)  Nondiscrimination. Loans shall be made available under this
     Section to all Participants on a reasonably equivalent basis, except that
     the Administrator may make reasonable distinctions based on
     creditworthiness.

          (k)  Employees no longer actively participating in Plan. For the
     avoidance of doubt, former Participants who are still employed by an
     Affiliated Employer shall be eligible to obtain loans under this Section
     12.3, subject to the rules set forth above. In the case of a loan to an
     individual described in the preceding sentence, the Administrator may make
     such arrangements as it deems advisable to provide for timely payment of

                                      -49-
<PAGE>

     amounts due on the loan. For purposes of eligibility to obtain loans
     pursuant to this Section 12.3(k), a former Participant who is employed by
     GTE Corporation (or any other entity which is aggregated with GTE
     Corporation and treated as a single employer pursuant to Code (S)(S)
     414(b), 414(c), 414(m), or 414(o)) immediately after the transfer of
     employment to GTE or an affiliate thereof in contemplation of or in
     connection with any initial public offering of the Company or any affiliate
     thereof, including the contemplated initial public offering of Genuity Inc.
     in 2000, shall be considered employed by an Affiliated Employer until the
     date such employee is provided the opportunity to have amounts in his
     Accounts transferred directly to a qualified retirement plan maintained by
     GTE Corporation or any such affiliate of GTE Corporation.

                                      -50-
<PAGE>

Article 13.    Distribution of Benefits.
               ------------------------

        13.1.  Methods of making distributions. All distributions from the Trust
shall be paid in cash. A Participant or former Participant may elect in writing,
on such form as the Administrator may prescribe, to receive distribution of his
benefits either in a single lump sum payment or in installments over a period
not to exceed fifteen (15) years.

     If distribution is to be made in installments, the following special rules
will apply: (i)  The amount of each distribution must be at least equal to the
quotient obtained by dividing the value of the interest of the distributee under
the Plan, determined as of the most recent valuation date, by the number of
payments remaining to be made; and (ii) the installment payment period shall in
no event exceed the life expectancies of the Participant or former Participant
and his designated Beneficiary.   Death benefits shall be distributed in a lump
sum; provided, that if a Participant or former Participant had begun to receive
his benefit in installments and died before distribution was completed, the
remaining benefit shall be distributed (A) to the extent payable to the
Participant's estate or to a Beneficiary that is not a "designated Beneficiary"
(as that term is used in Section 401(a)(9) of the Code), in a single lump sum;
and (B) to the extent distributable to a "designated Beneficiary" (as that term
is used in Section 401(a)(9) of the Code), in accordance with the same
installment schedule as applied to the Participant's benefits, unless the
Beneficiary elects a lump-sum commutation of the remaining payments.

        13.2.  Distributions.  If the aggregate benefit to which a Participant
is entitled under Articles 9 or 11 does not exceed $3,500, the benefit shall be
determined and distributed in a single payment as soon as reasonably practicable
following the date of retirement or other

                                      -51-
<PAGE>

separation from service. If the aggregate benefit to which a Participant is
entitled exceeds $3,500, distribution shall be deferred until the date on which
he attains age 70 1/2 unless he consents to an earlier distribution. The
determination as to whether a Participant's aggregate benefit exceeds $3,500 in
value shall be made consistent with Code (S) 411(a)(11) and the regulations
thereunder, and the Participant shall be given notice adequate under those
provisions of his right to defer receipt of a benefit in excess of $3,500.

     A former Participant whose distribution is deferred under this Section
shall continue to have the right to invest and reinvest his Accounts in
accordance with Article 6 and the procedures established thereunder.

        13.3.  Latest commencement date for benefits.  Notwithstanding any other
provision of the Plan to the contrary:

               (a)  Unless the Participant or former Participant otherwise
     elects (e.g., under Section 13.2 above), payment of benefits to the
     Participant or former Participant will not commence later than the sixtieth
     (60th) day after the latest of the following:

                    (i)    the close of the Plan Year in which the Participant
          or former Participant attains age sixty-five (65);

                    (ii)   the close of the Plan Year in which occurs the tenth
          (l0th) anniversary of the year in which the Participant or former
          Participant commenced participation in the Plan; or

                    (iii)  the close of the Plan Year in which the Participant
          or former Participant ceases to be an Employee.

                                      -52-
<PAGE>

               (b)  In any case, payment of benefits to a Participant or former
     Participant shall commence not later than by April 1 (the "required
     beginning date") next following the later of (i) the calendar year in which
     the individual attains age 70 1/2, and (ii) the calendar year in which the
     individual retires; provided, that in the case of an individual who (A)
     attained age 70 1/2 before January 1, 1988 and was a "five percent owner"
     (as defined in Section 416(i) of the Code) at any time during the Plan Year
     ending within the calendar year in which such individual attained age 66
     1/2 or any subsequent year, or (B) who attained age 70 1/2 on or after
     January 1, 1988 and is (or was) a "five percent owner" (as so defined) with
     respect to the Plan Year ending in the calendar year in which such
     individual attained age 70 1/2, the provisions of this subsection (b) shall
     be applied without regard to clause (ii). An individual not described in
     (A) or (B) above who attains age 70 1/2 and does not retire shall be
     entitled to a distribution under this subsection prior to retirement only
     to the extent, if any, required under Section 411(d)(6) of the Code, taking
     into account the provisions of the Plan as in effect prior to January 1,
     1997 and the provisions of the Small Business Job Protection Act of 1996.

               (c)  If a Participant or former Participant dies prior to
     attainment of his required beginning date, or after that date but prior to
     actual commencement of his benefit, the Participant's or former
     Participant's entire vested interest shall be distributed not less rapidly
     than (A) in full within five years following death, or (B) commencing by
     December 31 of the calendar year including the first anniversary of his
     death, over a period not greater than the life expectancy of the designated
     Beneficiary. However, if the

                                      -53-
<PAGE>

     Participant's designated Beneficiary is his surviving spouse, the
     commencement date described in clause (B) of the immediately preceding
     sentence need not be earlier than the date on which the Participant would
     have attained age 70 1/2. If a Participant or former Participant dies after
     attaining his required beginning date and after distribution of his
     benefits has commenced hereunder, but before such distribution has been
     completed, the remaining payments shall be distributed to his Beneficiary
     at least as rapidly as under the method of distribution under which the
     Participant or former Participant was receiving his benefits as of the date
     of his death. For purposes of this paragraph, under regulations prescribed
     by the Secretary of the Treasury, any amount paid to a child shall be
     treated as if it had been paid to the surviving spouse if such amount will
     become payable to the surviving spouse when the child reaches his majority,
     or upon such other designated event or events as may be permitted by
     regulations. The provisions of this Section are intended to comply with
     Code (S) 401(a)(9) and shall be construed and applied in a manner
     consistent with that section.

        13.4.  Cessation of interest in Plan. Upon the delivery to any
Participant, former Participant or other person of a lump sum payment or the sum
of all installment payments, the interest of said Participant, former
Participant or other person in the Plan shall cease and terminate.

                                      -54-
<PAGE>

Article 14.    Direct Rollovers of Eligible Distributions.
               ------------------------------------------

        14.1.  In General.  A distributee may elect, at the time and in the
manner prescribed by the Administrator, a direct rollover of any portion of an
eligible retirement distribution to an eligible retirement plan specified by the
distributee.

        14.2.  Definitions.  For purposes of this Section, the following
definitions shall apply:

               (a)  An "eligible rollover distribution" is any distribution of
     all or any portion of the balance to the credit of the distributee, except
     that an eligible rollover distribution does not include: any distribution
     that is one of a series of substantially equal periodic payments (not less
     frequently than annually) made for the life (or life expectancy) of the
     distributee and the distributee's Beneficiary, or for a specified period of
     ten years or more; any distribution that is required under Code (S)
     401(a)(9); the portion of any distribution that is not includible in gross
     income; and any distribution reasonably expected (determined in accordance
     with Code (S) 3405 and regulations promulgated thereunder, or any successor
     provision) to total less than $200 or any lower minimum amount specified by
     the Administrator.

               (b)  With respect to a distributee other than the Participant's
     surviving spouse, an "eligible retirement plan" is an individual retirement
     account described in Code (S) 408(a), an individual retirement annuity
     described in Code (S) 403(a), or a qualified trust described in Code (S)
     401(a). With respect to a distributee who is a Participant's or former
     Participant's surviving spouse, an eligible retirement plan is an
     individual retirement account or individual retirement annuity.

                                      -55-
<PAGE>

               (c)  A "distributee" includes an employee or former employee. In
     addition, the employee's surviving spouse and the employee's or former
     employee's spouse or former spouse, who is an alternate payee under a
     Qualified Domestic Relations Order, are distributees with regard to the
     interest of the spouse or former spouse.

               (d)  A "direct rollover" is a payment by the Plan to the eligible
     retirement plan specified by the distributee.

        14.3.  Notice requirement.  The Administrator shall give a distributee
notice of his right to elect a direct rollover and an explanation of the
withholding consequences of not making the election. Such notice shall be given
no earlier than 90 days and no later than 30 days before the date of
distribution. The distributee, in his sole discretion, may waive, in writing,
the right to 30 days' notice.

                                      -56-
<PAGE>

Article 15.    Special Top Heavy Provisions.
               ----------------------------

     In the event that the Plan is "top heavy" (within the meaning of Code (S)
416) for any Plan Year, the provisions contained in Appendix II to this Plan
shall apply notwithstanding any provision of the Plan to the contrary.

                                      -57-
<PAGE>

Article 16.    Concerning the Trustees.
               -----------------------

        16.1.  Appointment of Trustee.  The Board of Directors shall designate
and appoint one or more persons to serve as Trustees. Any person appointed by
the Board of Directors to serve as Trustee shall become a Trustee upon written
acceptance of his appointment, and shall continue to serve as Trustee until he
resigns, his term expires, or he is removed in accordance with Section 16.9
below.

        16.2.  Powers of the Trustees.  The Trustees are authorized with respect
to any and all money and properties which constitute the Trust Fund:

               (a)  To hold uninvested from time to time, without liability for
     interest thereon, such sum of money as is necessary for the cash
     requirements of the Plan; also to keep such portion of the Trust Fund in
     cash or cash balances as the Trustees may from time to time deem to be in
     the best interests of the Trust Fund.

               (b)  To invest and reinvest the principal and income of the Trust
     Fund without distinction between principal and income. Any such investments
     and reinvestments shall not be restricted to property and securities of the
     character authorized for investment by Trustees under any present or future
     laws; and in making any investment or reinvestment, the Trustees shall not
     be limited by the proportion which the investment so to be made, either
     alone or in conjunction with any other property of the same or similar
     character then held or thereafter acquired, may bear to the entire amount
     of the Trust Fund.

                                      -58-
<PAGE>

               (c)  To retain any property at any time received by them as
     Trustees hereunder, whether or not such property is an authorized
     investment for Trustees and without regard to any requirement of
     diversification of trust investments.

               (d)  To sell any property included in the Trust Fund at such time
     and upon such terms and conditions as the Trustees deem appropriate. Such
     sales may be public or private, for cash or credit, or partly for cash and
     partly for credit, and may be made without notice or advertisement of any
     kind and without the approval of any court whatsoever.

               (e)  To exchange, mortgage, or lease any such property and to
     convey, transfer, or dispose of any such property on such terms and
     conditions as the Trustees deem appropriate.

               (f)  To grant options for the sale, transfer, exchange, or
     disposal of any such property.

               (g)  To exercise all voting rights pertaining to any securities;
     and to consent to or request any action on the part of the issuer of any
     such securities; and to give general or special proxies or powers of
     attorney with or without power of substitution; and to waive notice of
     meetings.

               (h)  To consent to or participate in amalgamations,
     reorganizations, recapitalizations, consolidations, mergers, liquidations,
     or similar transactions with respect to any securities and to accept and to
     hold any other securities issued in connection therewith.

                                      -59-
<PAGE>

               (i)  To deposit any securities in any voting trust, or with any
     protective or like committee, or with a trustee or with depositaries
     designated thereby, and to pay or agree to pay part of the expenses or
     assessments levied with respect to any securities so deposited.

               (j)  To exercise any subscription rights or conversion privileges
     with respect to any securities held in the Trust Fund.

               (k)  To collect and receive any and all money and other property
     of whatsoever kind or nature due or owing or belonging to the Trust Fund
     and to give full discharge and acquittance therefor; and to extend the time
     of payment of any obligation at any time owing to such Fund; and to bid in
     property on foreclosure; and to take deeds in lieu of foreclosure with or
     without paying a consideration therefor.

               (l)  To cause any securities or other property to be registered
     in, or transferred into, the name of one or more of the Trustees without
     any indication of their fiduciary capacity, or in the name of a nominee or
     to retain them unregistered and in form permitting transferability by
     delivery, but the books and records of the Trust shall at all times show
     that all such investments are a part of the Trust Fund.

               (m)  To make, execute, acknowledge, and deliver any and all
     deeds, leases, assignments, bills of sale or other instruments with respect
     to any real or personal property.

               (n)  To retain, manage, operate, repair, and improve any real or
     personal property.

                                      -60-
<PAGE>

               (o)  To settle, compromise, or submit to arbitration any claims,
     debts, or damages due or owing to or from the Trust; to commence or defend
     suits or legal proceedings whenever in their judgment any interest of the
     Trust requires it; and to represent the Trust in all suits or legal
     proceedings in any court of law or equity or before any other body or
     tribunal.

               (p)  To borrow money from others for the purpose of the Trust,
     upon such terms and conditions as the Company may authorize; and for any
     sum so borrowed the Trustees may issue their promissory note as the
     Trustees and secure the repayment thereof by the pledging of any securities
     or property in their possession as Trustees hereunder, and may pay interest
     at such reasonable rate as may be approved by the Company for any moneys so
     borrowed by them.

               (q)  To engage the services of legal counsel and other advisers
     and agents in the administration of the Trust and to pay reasonable fees
     for such services.

               (r)  Generally to do all such acts, execute all such instruments,
     take all such proceedings, and exercise all such rights and privileges with
     relation to any property constituting a part of such Fund as if the
     Trustees were the absolute owners thereof; and to deal with the Company as
     with any other person.

               (s)  With the exception of the investment and reinvestment of the
     Trust Fund, to delegate from time to time, by instrument in writing, to any
     firm, person, partnership, or corporation any of their powers or authority
     hereunder, such as (i) custody of the assets of

                                      -61-
<PAGE>

     the Trust; (ii) accounting of the Trust Fund and interests therein; (iii)
     distribution of benefits; and (iv) annual report on the status of the
     Trust.

               (t)  With respect to the investment and reinvestment of the Trust
     Fund, to appoint one or more investment managers to manage any assets of
     the Plan and Trust; provided, however, that any such investment manager (i)
     must be either (a) registered as an investment adviser under the Investment
     Advisers Act of 1940 or (b) a bank, as defined in that Act, and (ii) must
     acknowledge in writing that he is a fiduciary with respect to the Plan.

               (u)  With respect to the investment and reinvestment of the Trust
     Fund, to delegate from time to time, by instrument in writing, to any one
     Trustee the power and authority to open savings accounts and to do all such
     acts which such Trustee deems necessary or incidental to invest excess cash
     of the Trust Fund in short term investments, including United States
     Treasury Obligations, United States Government Agency obligations,
     certificates of deposit, repurchase agreements, bankers acceptances, prime
     commercial paper rated A/1/P/1/ or its equivalent, bank holding company
     paper issued by major United States banks, established money market funds
     and other similar type and quality investments; and to wire or transfer
     cash between banks to facilitate any of the above investments.

               (v)  To hold and continue to hold any investments in qualifying
     employer real property and qualifying employer securities within the
     meaning of Section 407(d) of ERISA to the extent permitted by law.

                                      -62-
<PAGE>

        16.3.  Voting of Stock and other securities.  Notwithstanding the
provisions of Section 16.2 above, the Trustees shall vote securities only in
accordance with the affirmative direction of the Participants, former
Participants and Beneficiaries to whose Accounts an interest in such securities
is allocated. The Administrator shall timely provide Participants, former
Participants and Beneficiaries entitled to direct the Trustees under this
Section with all pertinent shareholder information provided to shareholders
generally. Notwithstanding the preceding provisions of this paragraph (a), the
Trustees shall retain complete investment discretion (including the discretion
and responsibility to exercise voting and similar rights) with respect to assets
held in the Trustees' Fund.

        16.4.  Indemnification of Trustees.  The Company will indemnify and save
the Trustees harmless against any liabilities which they may incur in the
exercise and performance of their powers and duties hereunder, and if requested
at any time by a Trustee will assume the defense of any action, suit, or other
proceeding against such Trustee.

        16.5.  Compensation of Trustees and expenses of Plan and Trust.  The
Trustees will serve without remuneration (other than reimbursement for
reasonable expenses) except as may from time to time otherwise be agreed upon by
the Company and the Trustees consistent with ERISA. Unless paid by a
Participating Employer or by a distributee in connection with a distribution
from the Trust Fund, the expenses incurred by the Trustees in the performance of
their duties hereunder, including without limitation reasonable compensation for
agents and for the services of counsel rendered to the Trustees, fees of any
investment manager or managers appointed pursuant to Section 16.2(t), auditor's
fees, custodian fees, appraisal fees and expenses

                                      -63-
<PAGE>

incident thereto, and all other proper charges and disbursements of the
Trustees, including all taxes of any and all kinds whatsoever, including
interest and penalties, that may be levied or assessed under existing or future
laws of any jurisdiction upon or in respect of the Trust Fund or any money,
property or securities forming a part thereof, will be paid by the Trustees out
of the Trust Fund, and the same, to the extent they are not paid by a
Participating Employer, will constitute a charge on the Trust Fund. The Trustees
will determine what constitutes a reasonable expense of administering the Trust,
which determination in good faith will be final and conclusive on all persons
having any interest in the Trust. The Trustees will also pay out of the Trust
Fund any expenses of administering the Plan which the Administrator directs the
Trustees to pay pursuant to Section 3.7.

     Any amounts so paid out of the Trust Fund, unless allocable to the Account
of a particular distributee, will be apportioned among the individual Accounts
of Participants and former Participants in such manner as the Administrator in
its sole discretion may from time to time determine or, in the absence of a
determination by the Administrator, as the Trustees may determine.

        16.6.  Limits of Trustees' duties.  The duties of the Trustees shall be
only those which are set forth in this Agreement.

        16.7.  Reliance by Trustees on other persons.  To the extent permitted
by law, the Trustees may rely and act upon any writing from any person signing
on behalf of the Company or from any other person authorized by the
Administrator to give instructions concerning the Plan, and may conclusively
rely upon and be protected in acting upon any written order from the

                                      -64-
<PAGE>

Administrator or any other notice, request, consent, certificate or other
instructions or paper reasonably believed by the Trustees to have been executed
by a duly authorized person, so long as the Trustees act in good faith in taking
or omitting to take any such action. The Trustees need not inquire as to the
basis in fact of any statement in writing received from the Administrator or the
Company, except as may otherwise be required by law.

     The Trustees will be entitled to rely on the latest certificate they have
received from the Administrator as to any person or persons authorized to act
for the Administrator hereunder and to sign on behalf of the Administrator any
directions or instructions, until they receive from the Administrator written
notice that such authority has been revoked.

     Notwithstanding any provision contained herein, the Trustees will be under
no duty to take any action with respect to any Participant's or former
Participant's Accounts (other than as specified herein) unless and until the
Administrator furnishes the Trustees with written instructions on a form
acceptable to the Trustees and the Trustees consent thereto in writing.  Except
as may be required by law, the Trustees will not be liable for any action taken
pursuant to the Administrator's written instructions (nor for the purpose or
propriety of any distribution made thereunder) and may return any contribution
transmitted to the Trustees under the Plan unless accompanied by full and
complete instructions in writing as to the disposition of such contribution.

        16.8.  Consultation by Trustees with counsel.  The Trustees may consult
with legal counsel (who may or may not be counsel to a Participating Employer)
concerning any question which may arise with reference to their duties under
this Agreement, and the opinion of such

                                      -65-
<PAGE>

counsel shall to the extent permitted by law be full and complete protection in
respect of any action taken or suffered by the Trustees hereunder in good faith
and in accordance with the opinion of such counsel.

        16.9.  Resignation or removal.  Any Trustee may resign or the Board of
Directors may remove any Trustee at any time upon sixty (60) days' written
notice. Upon such resignation or removal becoming effective, the Trustee shall
perform all acts necessary to transfer the assets of this Trust to the remaining
or successor Trustees.

        16.10. Appointment of successor Trustee.  Resignation or removal of all
of the Trustees shall not terminate the Trust. The Board of Directors of the
Company shall designate and appoint any additional or successor Trustee or
Trustees. Any additional or successor Trustee shall have the same powers herein
conferred upon an original Trustee.

        16.11. Approval of accounts.  Within a reasonable period after the close
of each Plan Year and after the termination of the Trust, the Trustees shall
render to the Company accounts of their administration of this Trust during the
preceding Plan Year or interim period, including all allocations required by
Article 7 hereof for such Year. To the extent permitted by law, the written
approval of any account by the Board of Directors as to all matters and
transactions stated or shown therein shall be final and binding upon the
Participating Employers and all persons who then shall be or thereafter shall
become interested in this Trust. Failure of the Board of Directors to notify the
Trustees within ninety (90) days after the receipt of any account of its or
their disapproval of the account shall be the equivalent of written approval.

                                      -66-
<PAGE>

        16.12. Dispute as to persons entitled to payment.  If a dispute arises
as to the persons to whom payment or delivery of any funds or property is to be
made by the Trustees, the Trustees may retain such payment and postpone such
delivery until adjudication of such dispute has been made by a court of
competent jurisdiction, or until the Trustees have been indemnified to their
satisfaction against loss, or until such dispute has been settled by the persons
concerned.

        16.13. Action by majority.  The Trustees for the time being in office
may act by a majority. To the extent permitted by law, all decisions made by a
majority of the then Trustees or in accordance with the authorization of such
majority will be final, binding, and conclusive upon the Participant, each
former Participant, each other Trustee, and every other person interested or
concerned, whether or not then in being.

                                      -67-
<PAGE>

Article 17.    Amendment.
               ---------

     The Company reserves the right at any time or times to amend the provisions
of this Agreement to any extent and in any manner that it may deem advisable by
delivery to the Trustees of a written instrument duly authorized by the Board of
Directors making such amendment, such amendment to take effect retroactively if
such instrument so provides.  Upon delivery of such instrument to the Trustees,
this Agreement shall be deemed to have been amended in the manner set forth
therein, and all Participants and former Participants and all other persons
claiming any interest hereunder shall be bound thereby; provided that no
amendment

          (a)  shall cause or permit any property held subject to the terms of
     this Trust to be diverted to purposes other than for the exclusive benefit
     of the Participants and former Participant and their Beneficiaries, unless
     such amendment is required or permitted by law, governmental regulations or
     ruling;

          (b)  shall increase the duties or liabilities of the Trustees or the
     Administrator without their written consent;

          (c)  shall reduce the obligation, if any, of the Participating
     Employers to make a contribution hereunder with respect to a particular
     Plan Year unless such amendment is made on or before the last day of said
     Plan Year; nor

          (d)  shall decrease any Participant's accrued benefit (including any
     elimination or reduction of an early retirement benefit or a retirement-
     type subsidy, or elimination of an optional form of benefit), except as
     permitted under Code (S) 411(d)(6) and regulations thereunder.

                                      -68-
<PAGE>

Article 18.    Discontinuance of Contributions and Termination of Plan.
               -------------------------------------------------------

        18.1.  Termination of Plan by Company.  The Company has established the
Plan with the bona fide intention and expectation that contributions will
continue indefinitely, but the Company is not and shall not be under any
obligation or liability whatsoever to maintain the Plan for any given length of
time and may in its sole and absolute discretion terminate the Plan at any time
without any liability whatsoever for such discontinuance or termination.

        18.2.  Events resulting in termination of Plan.  The Plan shall
terminate upon the happening of any of the following events:

               (a)  Delivery to the Trustees of a notice of termination executed
     on behalf of the Company by authority of the Board of Directors, specifying
     the date as of which the Plan terminates.

               (b)  Adjudication of the Company as a bankrupt, or general
     assignment by the Company to or for the benefit of creditors, or
     dissolution of the Company.

Upon termination of the Plan, each Participant's interest in his Share of the
Trust Fund shall be fully vested and nonforfeitable (subject, however, to any
changes in value occurring prior to the distribution of his benefits) and the
Trustees shall, to the extent consistent with qualification under Sections
401(a) and 401(k) of the Code, (i) forthwith liquidate the Trust Fund; (ii)
cause the Trust to pay all expenses properly chargeable to the Trust; and (iii)
after proportional adjustment of Accounts to reflect such expenses, losses, or
profits of the Trust and reallocations to the date of liquidation, make
distribution in a lump sum cash payment of each Participant's,

                                      -69-
<PAGE>

former Participant's, and Beneficiary's remaining interest in the Plan or
transfer Accounts to another tax-qualified defined contribution plan, if any,
maintained by the Employer.

        18.3.  Termination of participation as to any Participating Employer or
group of Participants. The Board of Directors may terminate the participation in
the Plan of any Participating Employer or any group of Employees employed in a
separate business unit. In the case of any such termination that constitutes a
"partial termination" under Code (S) 411(d)(3), each affected Participant's
interest in his Share of the Trust Fund shall be fully vested and
nonforfeitable, subject, however, to any changes in value occurring prior to the
distribution of his benefits. The Board of Directors in its discretion may, but
need not, provide for accelerated vesting in the case of any such termination or
discontinuance that would not constitute a "partial termination". Benefits under
the Plan shall be distributed to affected Participants and former Participants
only upon their retirement, death, or other separation from service. To the
extent consistent with the continued qualification of the Plan and except as
otherwise determined by the Board of Directors, however, a Participant or former
Participant affected by a termination under this Section resulting in
accelerated vesting may elect, in writing, that an earlier distribution be made
in the form either of a single cash payment or installments over a period not to
exceed three (3) years.

        18.4.  Permanent discontinuance of contributions. A Participant's or
former Participant's interest in his Share of the Trust Fund shall become fully
vested and nonforfeitable if his Participating Employer permanently discontinues
contributions hereunder (irrespective of whether the Plan and Trust are
terminated), effective as of the date the Participating Employer

                                      -70-
<PAGE>

notifies the Trustees in writing of its final termination of contributions. This
Section shall not apply in the case of a temporary suspension of contributions.

        18.5. Merger or consolidation of Plan; transfer of Plan assets. In case
of any merger or consolidation of the Plan with, or transfer of assets and
liabilities of the Plan to, any other plan, provision will be made so that each
affected Participant and former Participant would, if the transferee plan then
terminated, receive a benefit immediately after the merger, consolidation or
transfer which is equal to or greater than the benefit he would have been
entitled to receive immediately before the merger, consolidation or transfer if
the Plan had then terminated.

                                      -71-
<PAGE>

Article 19.    Miscellaneous.
               -------------

        19.1.  Limitation of rights.  The adoption and maintenance of the Plan
and Trust shall not be deemed to be a contract between a Participating Employer
and any Participant, former Participant or other person. Nothing herein
contained shall be deemed to give to any Participant, former Participant or
other person the right to be employed by a Participating Employer or to
interfere with the right of a Participating Employer to discharge any
Participant or other person at any time.

        19.2.  Benefits provided solely from Trust.  All benefits payable under
the Plan shall be paid or provided for solely from the Trust and the Employers
assume no liability or responsibility therefor.

        19.3.  Nonalienability of benefits.  Except as otherwise provided under
the Plan, the interest hereunder of any Participant, former Participant or other
person shall not be subject to alienation, assignment, garnishment, attachment,
execution or levy of any kind, and any attempt to cause such benefits to be so
subjected will not be recognized, except to the extent required by law.

     The provisions of the preceding paragraph shall apply in general to the
creation, assignment or recognition of a right to any benefit payable with
respect to a Participant pursuant to a domestic relations order. Notwithstanding
the foregoing, if such order is a Qualified Domestic Relations Order, the
provisions of the preceding paragraph shall not apply.

                                      -72-
<PAGE>

     The provisions of the first paragraph of this Section shall not apply to
the judgment, order, decree or settlement agreement to the extent provided in
Code (S) 401(a)(13)(C) or ERISA (S) 206(d)(4).

        19.4.  Payment under Qualified Domestic Relations Orders.
Notwithstanding any provisions of the Plan to the contrary, if there is entered
any Qualified Domestic Relations Order that affects the payment of benefits
hereunder, such benefits shall be paid in accordance with the applicable
requirements of such Order. The Administrator shall establish reasonable
procedures to determine whether an order or other decree is a Qualified Domestic
Relations Order, and to administer distributions under such Orders. To the
extent required by a Qualified Domestic Relations Order, the Administrator shall
cause distributions to be made from a Participant's Accounts to alternate payees
named in such Order in a manner consistent with the distribution options
otherwise available under the Plan.

        19.5.  Acceptance of Trust; governing law.  The Trustees hereby accept
the Trust herein expressed and agree to carry out the provisions hereof on their
part to be performed. This instrument and the Trust created thereby shall be
construed, administered, regulated and governed in all respects under and by the
laws of Massachusetts, except to the extent those laws are preempted by ERISA.

        19.6.  Method of providing notice.  Any notice given or required to be
given by the Company, the Administrator or the Trustees hereunder shall be
deemed to have been validly given:

                                      -73-
<PAGE>

               (a)  if given orally (in person, by telephone or otherwise), or
     delivered personally, by the party giving the notice or by his
     representative, or

               (b)  to an active employee of a Participating Employer, if given
     in writing and mailed through the normal intra-company mailing methods, or
     if mailed (postage paid) to the last known residence address of such
     employee on file with the Personnel Department of the Participating
     Employer, or

               (c)  to a former employee of a Participating Employer, if given
     in writing and mailed (postage paid) to the last known address of such
     employee on file with the Personnel Department of the Participating
     Employer, or

               (d)  in any event, if the active or former employee of the
     Participating Employer becomes aware of the matter in any other manner.

Any notice given or required to be given by a Participant or former Participant
shall be in writing and shall be deemed to have been validly given:

               (a)  if delivered personally to the Administrator, or

               (b)  if mailed to and timely received by the Administrator,
     Genuity Savings Plan, 150 Cambridge Park Drive, Cambridge, Massachusetts
     02140.

        19.7.  Compliance with USERRA, etc.  Notwithstanding any provision of
this plan to the contrary, contributions, benefits and service credit with
respect to qualified military service will be provided in accordance with
Section 414(u) of the Internal Revenue Code. Loan payments will be suspended
under this plan as permitted under Section 414(u)(4) of the Internal Revenue
Code.

                                      -74-
<PAGE>

        19.8.  Compliance with Code (S) 401(a), (S) 401(k), etc.  The Plan is
intended to be qualified under Section 401(a) of the Code, and the cash-or-
deferred feature under the Plan is intended to be a qualified cash-or-deferred
arrangement as defined in Section 401(k) of the Code, and, to the extent
applicable, the multiple employer provisions of Section 413(b) of the Code. The
Plan shall in all respects be construed and administered in accordance with the
foregoing. Without limiting the foregoing, except as otherwise expressly
provided under the Plan (including the Appendices), no distributions shall be
made to a Participant or former Participant unless the Participant has separated
from service (as that term is used under Section 401(k)(2)(B)(i)(I) of the
Code), died or suffered a disability as described in Section 9.2; provided, that
the Administrator may, in connection with the disposition to another corporation
of any subsidiary or the disposition to another corporation of substantially all
the assets used in any trade or business, provide for distributions to
Participants or former Participants continuing service with the acquiring
corporation to the extent permitted by and in accordance with the provisions of
Section 401(k)(10) of the Code. A determination by the Board of Directors
pursuant to the preceding sentence in the case of one disposition shall not
affect the distributability of benefits not affected by such disposition and
shall not bind the Board of Directors in other transactions.

        19.9.  Certain trustee-to-trustee transfers. In connection with the
transfer of employment of a Participant or former Participant from the employ of
a Participating Employer to the employ of an Affiliated Employer that is not a
Participating Employer and that maintains another plan qualified under Section
401(a) of the Code (the "transferee plan"), the Trustees may, but shall not be
obligated to, cause the Accounts of such Participant or former Participant to

                                      -75-
<PAGE>

be transferred to the transferee plan, but only if (a) such transfer complies
with Section 414(l) of the Code, and (b) the transferee plan provides the
Trustees or the Administrator with evidence satisfactory to them that the
transferee plan is qualified under Section 401(a) of the Code, and (c) the
transfer will not result in a violation of Section 411(d)(6) of the Code with
respect to the transferred Accounts. In the case of a Participant who was
formerly employed by an Affiliated Employer that maintains a profit-sharing plan
qualified under Section 401(a) (the "transferor plan") and for whom an account
or accounts were accrued under the transferor plan, the Trustees may, but shall
not be obligated to, accept a direct trust-to-trust transfer of assets and
liabilities from the transferor plan to the Trust, but only if the Trustees
determine that (i) the transferor plan is qualified under Section 401(a) of the
Code, and (ii) such transfer would comply with Section 414(l) of the Code. In
the case of any amount transferred to the Trust pursuant to the preceding
sentence, the Trustees or the Administrator shall establish such additional
accounts as they deem necessary to satisfy the requirement of the Plan and the
Code with respect to such transferred amounts, and to the extent such
transferred amounts are subject to distribution or other provisions protected
under Section 411(d)(6) of the Code that differ from the provisions applicable
generally under the Plan, the provisions applicable generally under the Plan
shall be deemed to have been modified to accommodate such protections. The
Trustees and the Administrator may exercise their discretion under this Section
on a case by case basis or in categories of cases.

                                      -76-
<PAGE>

     IN WITNESS WHEREOF, BBN Corporation has caused this instrument of amendment
to be executed by its duly authorized officer this ___ day of ________, 1999.

                                    BBN CORPORATION
                                    By:
                                       -------------------------------------
The foregoing Second Amendment is      The foregoing Second Amendment is
hereby consented to by the Trustees    hereby consented to by the
as of the date set forth above:        Administrator as of the date
the date set forth above:              set forth above:
___________________________________    _____________________________________
___________________________________    _____________________________________
___________________________________    _____________________________________
                                       _____________________________________

                               Consented to by the Administrator:
                               ______________________________
                               ______________________________
                               ______________________________

                                      -77-
<PAGE>

APPENDIX I -- SPECIAL RULES RELATING TO (S) 401(k) AND (S) 401(m) TESTING

I.1. In General.  Under the Code and applicable regulations, Pre-Tax
Contributions are required to satisfy certain nondiscrimination requirements and
are subject to special dollar limits. Employee After-Tax Contributions and
Matching Contributions are subject to nondiscrimination limits that are similar
to, and must be coordinated with, the nondiscrimination limits applicable to
Pre-Tax Contributions. The provisions of this Appendix I set forth the detailed
provisions that must be applied to satisfy these requirements and limits. These
provisions are to be construed in a manner consistent with the related
provisions of the Code and applicable regulations. To the extent any
Participating Employers to which this Appendix applies are Affiliated Employers
solely by reason of the last sentence of Section 2.3, the provisions of this
Appendix shall, to the extent required by the Code and applicable regulations,
be applied separately with respect to each such Participating Employer.

I.2. Certain Definitions.  Terms used in this Appendix which are defined in
Article 2 of the Plan have the meaning given them in Article 2. The following
additional defined terms have the meanings set forth below:

     (a)  "Compensation": except as otherwise specified, an individual's
          "compensation" as defined in Code (S) 414(s) and the regulations
          thereunder. The Administrator may elect to satisfy the
          nondiscrimination requirements set forth below in Section I.4 and
          Section I.5 below using any definition of Compensation acceptable
          under Code (S) 414(s) and the regulations thereunder, but for any Plan
          Year the same definition must be used for all purposes under Section
          I.4 and Section I.5. Solely for purposes of Section I.2(b) below (the
          definition of "Highly Compensated Employee"), the term Compensation
          means "compensation" as defined in Regs. (S) 1.415-2(d)(3) but without
          regard to reductions attributable to Pre-Tax Contributions, elective
          deferrals (as defined in Code (S) 402(g)(3)) under any other plan of
          the Employers, or salary-reduction contributions under any Code (S)
          125 cafeteria plan of the Employers.

     (b)  "Highly Compensated Employee":  an Employee who:

               (1)  is or was a 5% owner (as defined in Code (S) 416(i)(1))
               during the Plan Year for which a determination is being made or
               the immediately preceding Plan Year; or

               (2)  had Compensation from the employer in excess of $80,000
               (indexed in accordance with Code (S) 414(q)) during the Plan Year
               immediately preceding the Plan Year for which a determination is
               being made.

                                      -78-
<PAGE>

     (c)  "Qualified Nonelective Contribution" or "QNEC": a Primary Contribution
          which the Administrator elects to have treated as a "qualified
          nonelective contribution" within the meaning of Code (S) 401(m)(4)(C).
          Under specified circumstances described in Treas. Regs. (S) 1.401(k)-
          1(b)(5) and Treas. Regs. (S) 1.401(m)-1(b)(5), a QNEC may be treated
          as a Pre-Tax Contribution or as a Matching Contribution for purposes
          of satisfying the nondiscrimination rules set forth in I.4 and I.5
          below. Except as expressly authorized in regulations or other guidance
          under Code (S) 401(k) or (S) 401(m) of the Code, the same QNEC may not
          be used to satisfy both the ADP tests set forth in I.4 below and the
          ACP tests set forth in I.5 below.

     (d)  "Qualified Matching Contribution" or "QMAC": A Matching Contribution
          which the Administrator elects to use in satisfying the ADP tests of
          I.4. below. A QMAC shall not also be counted as a Matching
          Contribution for purposes of the ACP tests set forth in I.5 below.

I.3.      Dollar limit on Pre-Tax Contributions.
          -------------------------------------

          (a)  The maximum amount of Pre-Tax Contributions for the benefit of
          any Participant for any calendar year, when added to the elective
          deferrals (as defined in Code (S) 402(g)(3)), if any, made for his
          benefit under any other plan of the Employer, shall in no event exceed
          $7000 or such higher amount as the Secretary of the Treasury may
          determine under Code (S) 402(g)(5).

          (b)  If elective deferrals (as defined in Code (S) 402(g)(3)) have
          been made for a Participant's benefit for a calendar year in excess of
          the limit described in (a) above, the amount of such excess (the
          "excess deferral") shall be treated as follows: (i) to the extent the
          excess deferral is attributable to a failure to satisfy the
          limitations of (a) above (pertaining to the Plan and other plans, if
          any, maintained by the Employer), the Administrator shall cause the
          excess deferral to be distributed to the Participant not later than
          April 15 following the calendar year in which the excess deferral was
          made; and (ii) to the extent the excess deferral is attributable to
          elective deferrals under a plan or program maintained by an entity
          that is not an Employer, if the Participant so requests by March 1
          following the calendar year in which the excess deferral occurs,
          certifying in such request that he cannot obtain a distribution
          sufficient to correct the excess deferral from the other plan or
          program, the Administrator shall make every reasonable effort to cause
          such excess deferral to be corrected by distribution of an amount (not
          in excess of the Participant's Pre-Tax Deferrals for such calendar
          year plus income as hereinafter determined) from the Plan, which
          distribution shall be made, if at all, not later than April 15
          following the calendar year in which the excess deferral occurred. The
          amount so distributed under (i) or (ii) above shall take into account
          income allocable to the excess deferral

                                      -79-
<PAGE>

          (determined based on an allocable portion of the income attributable
          to the Participant's Pre-Tax Contribution Account), excluding,
          however, income earned following the end of the taxable year in which
          the deferral occurs, and shall be reduced by excess contributions (see
          below) that were previously distributed to him. No excess deferral may
          be distributed during the calendar year in which it was made, unless
          the distribution is made after the deferral has occurred and both the
          Participant and the Administrator have identified it as an excess
          deferral.

I.4.      ADP Tests, etc.
          --------------

               (a)  In General.  Pre-Tax Contributions, including for purposes
          of this Section I.4 both QNECs treated as Pre-Tax Contributions for
          purposes of satisfying the nondiscrimination rules of Code (S)
          401(a)(3) and QMACs, are subject to the limits of Code (S) 401(k)(3)
          as more fully described below.

               (b)  Actual deferral ratios. For each Plan Year, the
         Administrator will determine the "actual deferral ratio" for each
         Participant who is eligible for Pre-Tax Contributions. The actual
         deferral ratio shall be the ratio, calculated to the nearest one-
         hundredth of one percent, of the Pre-Tax Contributions made for the
         benefit of the Participant for the Plan Year, to the Participant's
         Compensation for the applicable period. For purposes of determining a
         Participant's actual deferral ratio:

                    (1)  Pre-Tax Contributions will be taken into account only
               if each of the following requirements are satisfied:

                         (i)  the Pre-Tax Contribution is allocated to the
                    Participant's Pre-Tax Contribution Account as of a date
                    within the Plan Year, is not contingent upon participation
                    in the Plan or performance of services on any date
                    subsequent to that date, and is actually paid to the Trust
                    no later than the end of the 12-month period immediately
                    following the Plan Year to which the contribution relates;
                    and

                         (ii) the Pre-Tax Contribution relates to 401(k)
                    Credited Compensation that either would have been received
                    by the Participant in the Plan Year but for the
                    Participant's election to defer under the Plan or is
                    attributable to services performed in the Plan Year and, but
                    for the Participant's election to defer, would have been
                    received by the Participant within 2 1/2 months after the
                    close of the Plan Year.

               To the extent Pre-Tax Contributions which meet the requirements
               of (i) and (ii) above constitute excess deferrals, they will be
               taken into account

                                      -80-
<PAGE>

               for each Highly Compensated Employee, but will not be taken into
               account for any non-Highly Compensated Employee.

                    (2)  in the case of a Participant who is a Highly
               Compensated Employee for the Plan Year and is eligible to have
               elective deferrals (or qualified nonelective or qualified
               matching contributions , to the extent treated as elective
               deferrals) allocated to his accounts under two or more cash or
               deferred arrangements described in Code (S) 401(k) maintained by
               an Affiliated Employer, the Participant's actual deferral ratio
               shall be determined as if such elective deferrals (as well as
               qualified nonelective or qualified matching contributions) are
               made under a single arrangement, and if two or more of the cash
               or deferred arrangements have different Plan Years, all cash or
               deferred arrangements ending with or within the same calendar
               year shall be treated as a single arrangement;

                    (3)  the applicable period for determining Compensation for
               each Participant for a Plan Year shall be the 12-month period
               ending on the last day of such Plan Year; provided, that to the
               extent permitted under regulations, the Administrator may choose,
               on a uniform basis, to treat as the applicable period only that
               portion of the Plan Year during which the individual was a
               Participant;

                    (4)  in the event that the Plan satisfies the requirements
               of Code (S)(S) 401(k), 410(a)(4), or 410(b) only if aggregated
               with one or more other plans with the same plan year, or if one
               or more other plans with the same plan year satisfy such Code
               sections only if aggregated with this Plan, then this section
               shall be applied by determining the actual deferral ratios as if
               all such plans were a single plan; and

                    (5)  Pre-Tax Contributions which are made for the benefit of
               non-Highly Compensated Employees which could be used to satisfy
               the Code (S) 401(k)(3) limits but are not necessary to be taken
               into account in order to satisfy such limits, may instead be
               taken into account for purposes of the Code (S) 401(m) limits to
               the extent permitted by Treas. Regs. (S) 1.401(m)-1(b)(5).

               (c)  Actual deferral percentages. The actual deferral ratios for
         all Highly Compensated Employees who are eligible for Pre-Tax
         Contributions for a Plan Year shall be averaged to determine the actual
         deferral percentage for the highly compensated group for the Plan Year,
         and the actual deferral ratios for all Employees who are not Highly
         Compensated Employees but are eligible for Pre-Tax Contributions for
         the Plan Year shall be averaged to determine the actual

                                      -81-
<PAGE>

         deferral percentage for the nonhighly compensated group for the Plan
         Year. The actual deferral percentages for any Plan Year must satisfy at
         least one of the following tests:

                    (1)  the actual deferral percentage for the highly
               compensated group does not exceed 125% of the actual deferral
               percentage for the nonhighly compensated group; or

                    (2)  the excess of the actual deferral percentage for the
               highly compensated group over the actual deferral percentage for
               the nonhighly compensated group does not exceed two percentage
               points, and the actual deferral percentage for the highly
               compensated group does not exceed twice the actual deferral
               percentage of the nonhighly compensated group.

         (d)   Adjustments by Administrator.  If, prior to the time all Pre-Tax
     Contributions for a Plan Year have been contributed to the Trust, the
     Administrator determines that Pre-Tax Contributions are being made at a
     rate which will cause the Code (S) 401(k)(3) limits to be exceeded for the
     Plan Year, the Administrator may, in its sole discretion, limit the amount
     of Pre-Tax Contributions to be made with respect to one or more Highly
     Compensated Employees for the balance of the Plan Year by suspending or
     reducing Pre-Tax Contribution elections to the extent the Administrator
     deems appropriate. Any Pre-Tax Contributions which would otherwise be made
     to the Trust shall instead be paid to the affected Participant in cash.

         (e)   Excess contributions.  If the Code (S) 401(k)(3) limits have not
     been satisfied for a Plan Year after all contributions for the Plan Year
     have been made, the Administrator will distribute excess contributions as
     provided below. In no event will excess contributions remain unallocated or
     be allocated to a suspense account for allocation in a future Plan Year.

               (1)  The Administrator will first determine the amount of excess
          contributions to be distributed to Participants who are highly
          Compensated Employees. Solely for purposes of determining the amount
          of excess contributions to be distributed, the Administrator will
          reduce the actual deferral ratio of the Highly Compensated Employee(s)
          with the highest actual deferral ratio to the extent necessary to (i)
          enable the Plan to satisfy the 401(k)(3) limits or (ii) cause such
          employee's or (employees') actual deferral ratio to equal the actual
          deferral ratio of the Highly Compensated Employee(s) with the next
          highest actual deferral ratio, and will repeat this process until the
          Plan satisfies the Code (S) 401(k)(3) limits. The amount of excess
          contributions for each Highly Compensated Employee for the Plan

                                      -82-
<PAGE>

          Year shall equal the amount of Pre-Tax Contributions actually made to
          the Trust for the Plan Year, less the product of the (i) the Highly
          Compensated Employee's reduced actual deferral ratio as determined
          under the preceding sentence, and (ii) his Compensation. The total
          amount of excess contributions for the Plan Year shall equal the sum
          of the excess contributions for each Highly Compensated Employee.

               (2)  The Administrator will then allocate the total amount of
          excess contributions for the Plan Year to the Highly Compensated
          Employees and distribute the amount allocated to each such employee.
          To do so, the Administrator will reduce the Pre-Tax Contributions of
          the Highly Compensated Employee(s) with the greatest amount of Pre-Tax
          Contributions for the Plan Year to the extent necessary to (i) equal
          the total excess contributions for the year (when added to the amount
          by which all other Pre-Tax Contributions are reduced) or (ii) cause
          the amount of such employee's (or employees') Pre-Tax Contributions to
          equal the Pre-Tax Contributions of the Highly Compensated Employee(s)
          having the next highest amount of Pre-Tax Contributions for such Plan
          Year. This process shall continue until all excess contributions for
          the Plan Year have been allocated and then distributed. If the excess
          contributions are allocated and distributed as provided herein, the
          test provided in Code (S) 401(k)(3) shall be deemed to be satisfied
          regardless of whether the test provided in Section I.4(c), if
          recalculated after distribution of the excess contribution, would
          satisfy Code (S) 401(k)(3). For purposes of Code (S) 401(m)(9), if a
          corrective distribution of excess contributions has been made, or a
          recharacterization has occurred, the actual deferral percentage for
          Highly Compensated Employees shall be deemed to be the largest amount
          permitted under Code (S) 401(k)(3).

          (f)  Distribution of excess contributions. A Participant's excess
     contributions, adjusted for income, will be designated by the Participating
     Employer as a distribution of excess contributions and distributed to the
     Participant. The income allocable to excess contributions is equal to the
     allocable gain or loss for the Plan Year, but not the allocable gain or
     loss for the period between the end of the Plan Year and the date of
     distribution (the "gap period"). Income allocable to excess contributions
     for the Plan Year shall be determined by multiplying the gain or loss
     attributable to the Participant's Pre-Tax Contribution Account (plus such
     portion of any other Account or Accounts attributable to QNECs or QMACs) by
     a fraction, the numerator of which is the excess contributions for the
     Participant for the Plan Year, and the denominator of which is the sum of
     (i) the balances of the Participant's Pre-Tax Contribution Account and any
     other Account or Accounts attributable to QNECs or QMACs, determined as of
     the beginning of the Plan Year,

                                      -83-
<PAGE>

     plus (ii) Pre-Tax Contributions for the Plan Year. Distribution of excess
     contributions will be made after the close of the Plan Year to which the
     contributions relate, but within 12 months after the close of such Plan
     Year. Excess contributions shall be treated as Annual Additions under the
     Plan, even if distributed under this paragraph.

          (g)  Special rules.  For purposes of distributing excess
     contributions, the amount of excess contributions that may be distributed
     with respect to a Highly Compensated Employee for a Plan Year shall be
     reduced by the amount of excess deferrals previously distributed to the
     Highly Compensated Employee for his taxable year ending with or within such
     Plan Year.

          (h)  Recordkeeping requirement. The Administrator, on behalf of the
     Participating Employers, shall maintain such records as are necessary to
     demonstrate compliance with the Code (S) 401(k)(3) limits, including the
     extent to which QNECs and QMACs are taken into account in determining the
     actual deferral ratios.

          (i)  Effect on Matching Contributions. A Participant's Pre-Tax
     Contributions which are returned as a result of the Code (S) 401(k)(3)
     limits for a Plan Year shall not be taken into account in determining the
     amount of Matching Contributions to be made for the Participant's benefit
     for the Year. To the extent Matching Contributions have already been made
     with respect to the Pre-Tax Contributions at the time the Pre-Tax
     Contributions are determined to be excess contributions, such Matching
     Contributions shall be distributed to the Participant at the same time as
     the Pre-Tax Contributions are returned or recharacterized.

I.5. ACP Tests, etc.
     ---------------

          (a)  In General.  Matching Contributions and Employee After-Tax
     Contributions are subject to the limits of Code (S) 401(m), as more fully
     described below. When used in this Section I.5, the term "Matching
     Contribution" shall be deemed (i) to include any QNEC which is used to
     satisfy the ADP tests described in this Section and, to the extent
     consistent with Treas. Regs. (S) 1.401(m)-1(b)(5), any Pre-Tax
     Contributions not taken into account in applying the ADP tests described in
     Section I.4 above; and (ii) to exclude any QMAC.

          (b)  Actual contribution ratios.  For each Plan Year, the
     Administrator will determine the "actual contribution ratio" for each
     Participant who is eligible for Matching Contributions and/or Employee
     After-Tax Contributions. The actual contribution ratio shall be the
     ratio, calculated to the nearest one-hundredth of one percent, of the
     sum of the Matching Contributions and Employee After-Tax

                                      -84-
<PAGE>

         Contributions made by or on behalf of the Participant for the Plan
         Year, to the Participant's Compensation for the Plan Year. For purposes
         of determining a Participant's actual contribution ratio,

                    (1)  a Matching Contribution will be taken into account only
               if the Contribution is allocated to a Participant's Account as of
               a date within the Plan Year, is actually paid to the Trust no
               later than 12 months after the close of the Plan Year, and is
               made on behalf of a Participant on account of the Participant's
               Pre-Tax Contributions for the Plan Year;

                    (2)  in the case of a Participant who is a Highly
               Compensated Employee for the Plan Year and is eligible to have
               Matching Contributions or Employee After-Tax Contributions
               allocated to his accounts under two or more plans maintained by
               an Affiliated Employer which may be aggregated for purposes of
               Code (S)(S) 410(b) and 401(a)(4), the Participant's actual
               contribution ratio shall be determined as if such contributions
               are made under a single plan, and if two or more of the plans
               have different Plan Years, all plans ending with or within the
               same calendar year shall be treated as a single plan;

                    (3)  the applicable period for determining Compensation for
               each Participant for a Plan Year shall be the 12-month period
               ending on the last day of such Plan Year; provided, that to the
               extent permitted under Regulations, the Administrator may choose,
               on a uniform basis, to treat as the applicable period only that
               portion of the Plan Year during which the individual was a
               Participant;

                    (4)  in the event that the Plan satisfies the requirements
               of Code (S)(S) 401(k), 410(a)(4), or 410(b) only if aggregated
               with one or more other plans with the same plan year, or if one
               or more other plans with the same Plan Year satisfy such Code
               sections only if aggregated with this Plan, then this section
               shall be applied by determining the actual deferral ratios as if
               all such plans were a single plan;

          (c)  Actual contribution percentages.  The actual contribution ratios
     for all Highly Compensated Employees who are eligible to make Employee
     After-Tax Contributions or to share in Matching Contributions for a Plan
     Year shall be

                                      -85-
<PAGE>

     averaged to determine the actual contribution percentage for the highly
     compensated group for the Plan Year, and the actual contribution ratios for
     all Employees who are not Highly Compensated Employees but are eligible to
     make Employee After-Tax Contributions or to share in Matching Contributions
     for the Plan Year shall be averaged to determine the actual contribution
     percentage for the nonhighly compensated group for the Plan Year. The
     actual contribution percentages for any Plan Year must satisfy at least one
     of the following tests:

                    (1)  The actual contribution percentage for the highly
               compensated group does not exceed 125% of the actual contribution
               percentage for the nonhighly compensated group; or

                    (2)  The excess of the actual contribution percentage for
               the highly compensated group over the actual contribution
               percentage for the nonhighly compensated group does not exceed
               two percentage points, and the actual contribution percentage for
               the highly compensated group does not exceed twice the actual
               contribution percentage of the nonhighly compensated group.

          (d)  Multiple use test. In the event that (i) the actual deferral
     percentage and actual contribution percentage for the highly compensated
     group each exceed 125% of the respective actual deferral and actual
     contribution percentages for the nonhighly compensated group, and (ii) the
     sum of the actual deferral percentage and the actual contribution
     percentage for the highly compensated group exceeds the "aggregate limit"
     within the meaning of Regulation section 1.401(m)-2(b)(3), the
     Administrator shall reduce the amount of Matching Contributions and/or
     Employee After-Tax Contributions made for the benefit of Highly Compensated
     Employees who had both an actual deferral ratio and an actual contribution
     ratio to the extent required by such Regulation section and in the same
     manner as described in paragraphs (f) and (g) below.

          (e)  Adjustments by Administrator. If, prior to the time all Matching
     Contributions for a Plan Year have been contributed to the Trust, the
     Administrator determines that such Contributions are being made at a rate
     which will cause the Code (S) 401(m) limits to be exceeded for the Plan
     Year, the Administrator may, in its sole discretion, limit the amount of
     such Contributions to be made with respect to one or more Highly
     Compensated Employees for the balance of the Plan Year by limiting the
     amount of such Contributions to the extent the Administrator deems
     appropriate.

          (f)  Excess aggregate contributions. If the Code (S) 401(m) limits
     have not been satisfied for a Plan Year after all contributions for the
     Plan Year have been made,

                                      -86-
<PAGE>

     the Administrator will distribute excess aggregate contributions as
     provided below. In no event will excess aggregate contributions remain
     unallocated or be allocated to a suspense account for allocation in a
     future Plan Year.

               (1)  The Administrator will first determine the amount of excess
         aggregate contributions to be distributed to Participants who are
         Highly Compensated Employees. Solely for purposes of determining the
         amount of excess aggregate contributions to be distributed, the
         Administrator will reduce the actual contribution ratio of the Highly
         Compensated Employee(s) with the highest actual contribution ratio to
         the extent necessary to (i) enable the Plan to satisfy the section
         401(m) limits or (ii) cause such employee's (or employees') actual
         contribution ratio to equal the actual contribution ratio of the Highly
         Compensated Employee(s) with the next highest actual contribution
         ratio, and will repeat this process until the Plan satisfies the Code
         (S) 401(m) limits. The amount of excess aggregate contributions for
         each Highly Compensated Employee for the Plan Year shall equal the
         amount of Matching Contributions and Employee After-Tax Contributions
         actually made to the Trust for the Plan Year, less the product of the
         (i) the Highly Compensated Employee's reduced actual contribution ratio
         as determined under the preceding sentence, and (ii) his Compensation.
         The total amount of excess aggregate contributions for the Plan Year
         shall equal the sum of the excess aggregate contributions for each
         Highly Compensated Employee.

               (2)  The Administrator will then allocate the total amount of
         excess aggregate contributions for the Plan Year to the Highly
         Compensated Employees and distribute the amount allocated to each such
         employee. To do so, the Administrator will reduce the Matching
         Contributions and/or Employee After-Tax Contributions of the Highly
         Compensated Employee(s) with the greatest amount of such contributions
         for the Plan Year to the extent necessary to (i) equal the total excess
         aggregate contributions for the year (when added to the amount by which
         all other Matching and/or Employee After-Tax contributions are reduced)
         or (ii) cause the amount of such employee's (or employees') Matching
         and/or Employee After-Tax Contributions to equal the Matching and/or
         Employee After-Tax Contributions of the Highly Compensated Employee(s)
         having the next highest amount of such contributions for such Plan
         Year. This process shall continue until all excess aggregate
         contributions for the Plan Year have been allocated and then
         distributed. If the excess aggregate contributions are allocated and
         distributed as provided herein, the test provided in Code (S) 401(m)(2)
         shall be deemed to be satisfied regardless of whether the test provided
         in Section I.5(c), if

                                      -87-
<PAGE>

         recalculated after distribution of the excess contributions, would
         satisfy Code (S) 401(m)(2). For purposes of Code (S) 401(m)(9), if a
         corrective distribution of excess aggregate contributions has been
         made, or a recharacterization has occurred, the actual contribution
         percentage for Highly Compensated Employees shall be deemed to be the
         largest amount permitted under Code (S) 401(m)(2).

         (g)   Distribution of excess aggregate contributions. A Participant's
     excess aggregate contributions, adjusted for income will be designated by
     the Participating Employer as a distribution of excess aggregate
     contributions, and distributed to the Participant. The income allocable to
     excess aggregate contributions is equal to the allocable gain or loss for
     the taxable year of the individual, but not the allocable gain or loss for
     the period between the end of the taxable year and the date of distribution
     (the "gap period"). Income allocable to excess aggregate contributions for
     the taxable year shall be determined by multiplying the gain or loss
     attributable to the Participant's Matching Contribution Account
     (disregarding any portion thereof attributable to QMACs) and Employee
     After-Tax Contribution Account, plus that portion, if any, of the
     Participant's Primary Contribution Account attributable to Pre-Tax
     Contributions taken into account for purposes of satisfying the Code (S)
     401(m) limits (together: the "relevant accounts"), by a fraction, the
     numerator of which is the excess aggregate contributions for the
     Participant for the Plan Year, and the denominator of which is the sum of
     the Participant's relevant accounts determined as of the beginning of the
     Plan Year plus the Matching Contributions and Employee After-Tax
     Contributions made by or for the benefit of the Participant for the Plan
     Year. Distribution of excess aggregate contributions will be made after the
     close of the Plan Year to which the contributions relate, but within 12
     months after the close of such Plan Year. Excess aggregate contributions
     shall be treated as employer contributions for purposes of Code (S)(S)
     401(a)(4), 404, and 415 even if distributed from the Plan.

          (h)  Special Rules. For purposes of distributing excess aggregate
     contributions, distribution of excess aggregate contributions (in each case
     adjusted for income or loss) shall be accomplished in the following order:
     first, Employee After-Tax Contributions; and second, Matching
     Contributions.

          (i)  Recordkeeping requirement. The Administrator, on behalf of the
     Participating Employers, shall maintain such records as are necessary to
     demonstrate compliance with the Code (S) 401(m) limits, including the
     extent to which Pre-Tax Contributions and QNECs are taken into account in
     determining the actual contribution ratios.

                                      -88-
<PAGE>

APPENDIX II -- SPECIAL TOP HEAVY PROVISIONS

     II.1.     Provisions to apply.  The provisions of this Appendix II shall
apply for any top-heavy plan year notwithstanding anything to the contrary in
this Plan. All determinations hereunder will be made in accordance with the
provisions of Code (S) 416 and the regulations promulgated thereunder, which are
specifically incorporated herein by reference.

     II.2.     Minimum Contribution.  For any Plan Year which is a top-heavy
plan year, the Participating Employers shall contribute to the Trust a minimum
contribution on behalf of each Participant who is not a key employee for such
year and who has not separated from service by the end of the Plan Year. The
minimum contribution shall, in general, equal 3% of each such Participant's
"compensation" as defined in Regs. (S) 1.415-2(d)(2) (taking into account the
exclusions described in Regs. (S) 1.415-2(d)(3)), but shall be subject to the
following special rules:

               (a)  If the largest Participating Employer contribution on behalf
     of a key employee for such year, expressed as a percentage of
     "compensation" (as so defined), is less than 3 percent, such lesser
     percentage shall be the minimum rate of contribution percentage for
     Participants who are not key employees. This special rule shall not apply,
     however, if this Plan is required to be included in an aggregation group
     and enables a defined benefit plan to meet the requirements of Code (S)(S)
     410(a)(4) or 410.

               (b)  No minimum contribution will be required with respect to a
     Participant who is also covered by another top-heavy defined benefit
     contribution plan of an Affiliated Employer which meets the vesting
     requirements of Code (S) 416(b) and under which the Participant receives
     the top-heavy minimum contribution.

               (c)  No minimum contribution will be required with respect to any
     Participant who is also covered by a top-heavy defined benefit plan of an
     Affiliated Employer and who receives the top-heavy defined benefit minimum
     (within the meaning of Code (S) 416(c)(1) and the Regulations thereunder)
     under such defined benefit plan.

               (d)  Primary Contributions (other than any such contributions
     treated as QNECs) will count toward satisfying the minimum contribution
     required with respect to any Participant who is not a key employee.

               (e)  Any additional minimum contribution made for the benefit of
     a Participant under this Section shall be credited to the Participant's
     Primary Contribution Account as soon as practicable after the close of the
     Plan Year for which such contribution is made.

     II.3.     Special Vesting Schedule. In the case of any Employee who is a
Participant at any time during a top-heavy plan year, the determination of such
Employer's vested and nonforfeitable interest in his Primary Contribution
Account shall be determined under Section

                                      -89-
<PAGE>

11.2 by substituting the following alternative vesting schedule for the seven-
year vesting schedule set forth in said Section 11.2:

             Applicable
          Years of Service  Nonforfeitable Percentage
          ----------------  -------------------------

          less than 2                  0%
          2 but less than 3           20%
          3 but less than 4           40%
          4 but less than 5           60%
          5 but less than 6           80%
          6 or more                  100%

     II.4.     Definitions.  For purposes of these top-heavy provisions, the
following terms have the following meanings:

               (a)  "key employee" means a key employee described in Code (S)
     416(i)(1); and

               (b)  "top-heavy plan year" means a Plan Year if the sum of the
     Account balances of all key employees under the Plan and each other defined
     contribution plan (as of the applicable determination date of each such
     plan) which is aggregated with the Plan, plus the sum of the present values
     of the total accrued benefits of all key employees under each defined
     benefit plan (as of the applicable determination date of each such plan)
     which is aggregated with the Plan exceeds 60 percent of the sum of such
     amounts for all Employees (including, for purposes of this paragraph (b),
     any person employed by an Affiliated Employer) and former Employees (other
     than former key employees, but including Beneficiaries of former Employees)
     under the Plan and all such plans. For purposes of these determinations:

                    (i)  The term "determination date" means, with respect to
          the initial plan year of a plan, the last day of such plan year and,
          with respect to any other plan year of a plan, the last day of the
          preceding plan year of such plan. The term "applicable determination
          date" means, with respect to the Plan, the determination date for the
          Plan Year of reference and, with respect to any other plan, the
          determination date for any plan year of such plan which falls within
          the same calendar year as the applicable determination date of the
          Plan.

                    (ii) Accrued benefits or account balances under a plan will
          be determined as of the most recent valuation date of the plan in that
          12-month period ending on the applicable determination date of the
          plan; provided, however, that in the case of a defined benefit plan
          such valuation date must be the same date as is employed for minimum
          funding purposes, and in the case of a defined

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<PAGE>

          contribution plan the value so determined will be adjusted for
          contributions made after the valuation date to the extent required by
          applicable Regulations.

                   (iii) If any individual has not received any compensation
          from an Affiliated Employer maintaining a plan (other than benefits
          under the plan) at any time during the 5-year period ending on the
          applicable determination date with respect to such plan, any accrued
          benefit for such individual (and the account of such individual) under
          such plan shall not be taken into account.

                   (iv)  Each plan of an Affiliated Employer (whether or not
          terminated) in which a key employee participates, and any other plan
          of an Affiliated Employer which enables a plan referred to in the
          preceding clause to satisfy the requirements of Code (S)(S) 401(a)(4)
          and 410, shall be aggregated with the Plan. Any plan of an Affiliated
          Employer not required to be aggregated with the Plan may nevertheless,
          at the discretion of the Administrator, be aggregated with the Plan if
          the benefits and coverage of all aggregate plans would continue to
          satisfy the requirements of sections 401(a)(4) and 410 of the Code.

                   (v)   The determination of the present value of accrued
          benefits under a defined benefit plan shall be made on the basis of
          the funding assumptions employed by such plan.

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<PAGE>

APPENDIX III -- SALE OF ADVANCED SIMULATION BUSINESS

     Reference is made to the 1993 sale (the "Transaction") by the Company of
its advanced simulation business (the "Business") to Loral Advanced Distributed
Simulation, Inc. ("Loral").  Participants who were employed by, or provided
support services to, the Business on the closing date of the Transaction and who
ceased to be Employees by transferring to the employ of Loral in connection with
the transaction (each, a "Covered Participant") were fully vested in their
accrued benefits under the Plan as of such closing date.  Schedule A to this
Appendix II sets forth a complete list of all Covered Participants.  Each
Covered Participant shall be treated for all purposes of the Plan as a former
Participant described in the last sentence of Section 4.2 and shall be eligible
for a distribution in accordance with the generally applicable provisions of the
Plan upon separation from service with Loral and its affiliates (or, in the case
of a Participant entitled to benefits in excess of $7,500, one year following
the closing of the Transaction, if later), death, or disability as described in
Section 9.2; provided, that a Covered Participant shall in all events be
entitled to a distribution upon attaining age 65.  Notwithstanding the
foregoing, a Covered Participant shall be treated as an active Participant for
purposes of eligibility to receive loans under Section 12.3 of the Plan;
provided that, notwithstanding Section 12.3(j), the Administrator may at any
time and from time to time limit or restrict access to loans for Covered
Participants or impose special rules with respect to the availability, amount,
repayment terms or other terms of such loans if the Administrator deems such
limitations, restrictions or special rules necessary or advisable in order to
satisfy the requirements applicable to participant loans, or tax-qualification
requirements generally, under the Code.  The discretionary authority of the
Administrator described in the preceding sentence shall be in amplification and
not in limitation of the Administrator's other powers and authority under the
Plan.

     Notwithstanding the preceding provisions of this Appendix III, the Trustees
shall, if so authorized by the Board and in accordance with such procedures as
the Administrator may determine, transfer undistributed accrued benefits of
Covered Participants to a tax-qualified plan maintained by Loral Corporation or
its affiliates and specified for such purpose by Loral Corporation (the "Loral
Plan"), all in accordance with Section 414(l) of the Code and Section 18.5 of
the Plan.

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<PAGE>

APPENDIX IV -- SALE OF LIGHTSTREAM BUSINESS

     Reference is made to the sale by the Lightstream Corporation of certain
assets and business (the "Business") to Cisco Systems, Inc. ("Cisco") pursuant
to an Asset Purchase Agreement dated as of December 8, 1994 (the "Transaction").
Participants who were employed by, or provided support services to, the Business
on the closing date of the Transaction (January 11, 1995) and who ceased to be
Employees by transferring to the employ of Cisco in connection with the
transaction (each, a "Covered Participant") were fully vested in their accrued
benefits under the Plan as of such closing date.  Schedule A to this Appendix II
sets forth a complete list of all Covered Participants.  Each Covered
Participant shall be treated for all purposes of the Plan as a former
Participant described in the last sentence of Section 4.2 and shall be eligible
for a distribution in accordance with the generally applicable provisions of the
Plan upon separation from service with Cisco and its affiliates, death, or
disability as described in Section 9.2; provided, that a Covered Participant
shall in all events be entitled to a distribution upon attaining age 65.
Notwithstanding the foregoing, a Covered Participant shall be treated as an
active Participant for purposes of eligibility to receive loans under Section
12.3 of the Plan; provided that, notwithstanding Section 12.3(j), the
Administrator may at any time and from time to time limit or restrict access to
loans for Covered Participants or impose special rules with respect to the
availability, amount, repayment terms or other terms of such loans if the
Administrator deems such limitations, restrictions or special rules necessary or
advisable in order to satisfy the requirements applicable to participant loans,
or tax-qualification requirements generally, under the Code.  The discretionary
authority of the Administrator described in the preceding sentence shall be in
amplification and not in limitation of the Administrator's other powers and
authority under the Plan.

     Notwithstanding the preceding provisions of this Appendix IV, the Trustees
shall, if so authorized by the Board and in accordance with such procedures as
the Administrator may determine, transfer undistributed accrued benefits of
Covered Participants to a tax-qualified plan maintained by Cisco or its
affiliates and specified for such purpose by Cisco, all in accordance with
Section 414(l) of the Code and Section 18.5 of the Plan.

                                      -93-