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                                                                     EXHIBIT 4.2


                                  SYBASE, INC.
                            1991 AMENDED AND RESTATED
                          EMPLOYEE STOCK PURCHASE PLAN
                        (As amended on February 2, 2000)


1. Purpose

This Amended and Restated Sybase, Inc. 1991 Employee Stock Purchase Plan (the
"Plan") is designed to encourage and assist employees of Sybase, Inc. ("Sybase")
and participating subsidiaries (together, the "Company") to acquire an equity
interest in the Company through the purchase of shares of Sybase common stock
(the "Common Stock").

2. Administration

The Plan shall be administered by the Board of Directors of Sybase (or a
committee of "disinterested" directors no fewer in number than required by Rule
16b-3 of the Securities and Exchange Commission ("Rule 16b-3") as in effect with
respect to the Company from time to time, which in either case is referred to as
the "Board") in accordance with Rule 16b-3. The Board may from time to time
select a committee or persons (the "Administrator"), to be responsible for any
matters for which a "disinterested administrator" is not required by Rule 16-b.
Subject to the express provisions of the Plan, to the overall supervision of the
Board, and to the limitations of Section 423 of the Internal Revenue Code of
1986, as amended (the "Code"), the Administrator may administer and interpret
the Plan in any manner it believes to be desirable, and any such interpretation
shall be conclusive and binding on the Company and all participants.

3. Number of Shares

(a) The Company has reserved for sale under the Plan 11,800,000 shares of Common
Stock (after giving effect to the November 1993 2-for-1 stock split) less any
shares sold under the Sybase 1991 Amended and Restated Foreign Subsidiary
Employee Stock Purchase Plan. Shares sold under the Plan may be newly issued
shares or shares reacquired in private transactions or open market purchases,
but all shares sold under the Plan, regardless of source, shall be counted
against the 11,800,000 share limitation.

(b) In the event of any reorganization, recapitalization, stock split, reverse
stock split, stock dividend, combination of shares, merger, consolidation,
offering of rights, or other similar change in the capital structure of the
Company, the Board may make such adjustment, if any, as it deems appropriate in
the number, kind, and purchase price of the shares available for purchase under
the Plan and in the maximum number of shares subject to any option under the
Plan.

4. Eligibility Requirements

(a) Each employee of the Company, except those described in the next paragraph,
shall become eligible to participate in the Plan in accordance with Section 5 on
the first Enrollment Date on or following commencement of his or her employment
by the Company or following such period of employment as is designated by the
Board from time to time. Participation in the Plan is entirely voluntary.

(b) The following employees are not eligible to participate in the Plan:

(i) employees who would, immediately upon enrollment in the Plan, own directly
or indirectly, or hold options or rights to acquire stock possessing, five
percent or more of the total combined voting power or value of all classes of
stock of Sybase or any subsidiary of Sybase;



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(ii) employees who are categorized after August 31, 1999 as temporary employees
or who are customarily employed by the Company less than 20 hours per week or
less than five months in any calendar year; and

(iii) employees who are prohibited by the laws of the nation of their residence
or employment from participating in the Plan.

Employees who are also directors or officers of the Company may participate only
in accordance with Rule 16b-3 of the Securities and Exchange Commission.

(c) "Employee" shall mean any individual who is an employee of the Company or a
Participating Subsidiary within the meaning of Section 3401(c) of the Code and
the Treasury Regulations thereunder. "Subsidiary" shall mean any corporation
described in Section 425(e) or (f) of the Code. "Participating Subsidiary" shall
mean a subsidiary which has been designated by the Administrator as covered by
the Plan.

5. Enrollment

Any eligible employee may enroll or re-enroll in the Plan each year as of the
first trading day of (i) the month immediately following the closing of the
Company's initial public offering of shares of its Common Stock on a
Registration Statement on Form S-1 (except that if such closing occurs during
the last month of a fiscal quarter (e.g. September), then the first Enrollment
Date will be the first trading day of the second month of the quarter
immediately following the closing (e.g. November)), (ii) the sixth month
following such month, and (iii) each yearly anniversary of such months (e.g. any
March and September or May and November), or such other days as may be
established by the Board from time to time (the "Enrollment Dates"). In order to
enroll, an eligible employee must complete, sign, and submit to the Company an
enrollment form. Any enrollment form received by the Company by the 15th day of
the month preceding an Enrollment Date (or by the Enrollment Date in the case of
employees hired after such 15th day), or such other date established by the
Administrator from time to time, will be effective on that Enrollment Date. For
purposes of the Plan, a "trading day" is any day on which regular trading occurs
on any established stock exchange or market system on which the Common Stock is
traded.

6. Grant of Option on Enrollment

(a) Enrollment or re-enrollment by a participant in the Plan on an Enrollment
Date will constitute the grant by the Company to the participant of an option to
purchase shares of Common Stock from the Company under the Plan. Any participant
whose option expires and who has not withdrawn from the Plan will automatically
be re-enrolled in the Plan and granted a new option on the Enrollment Date
immediately following the date on which the option expires.

(b) Except as provided in Section 9, each option granted under the Plan shall
have the following terms:

(i) each option granted under the Plan will have a term of not more than 24
months or such shorter option period as may be established by the Board from
time to time; notwithstanding the foregoing, however, whether or not all shares
have been purchased thereunder, the option will expire on the earlier to occur
of (A) the completion of the purchase of shares on the last Purchase Date
occurring within 24 months after the Enrollment Date for such option, or such
shorter option period as may be established by the Board before an Enrollment
Date for all options to be granted on such date or (B) the date on which the
employee's participation in the Plan terminates for any reason;

(ii) payment for shares purchased under the option will be made only through
payroll withholding in accordance with Section 7;

(iii) purchase of shares upon exercise of the option will be effected only on
the Purchase Dates established in accordance with Section 8;



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(iv) the price per share under the option will be determined as provided in
Section 8;

(v) the number of shares available for purchase under the option will, unless
otherwise established by the Board before an Enrollment Date for all options to
be granted on such date, be determined by dividing $25,000 by the fair market
value of a share of Common Stock on the Enrollment Date and by multiplying the
result by the number of calendar years included in whole or in part in the
period from grant to expiration of the option;

(vi) the option (taken together with all other options then outstanding under
this and all other similar stock purchase plans of Sybase and any subsidiary of
Sybase, collectively "Options") will in no event give the participant the right
to purchase shares at a rate per calendar year which accrues in excess of
$25,000 of fair market value of such shares, less the fair market value of any
shares accrued and already purchased during such year under Options which have
expired or terminated, determined at the applicable Enrollment Dates; and

(vii) the option will in all respects be subject to the terms and conditions of
the Plan, as interpreted by the Administrator from time to time.

7. Payroll and Tax Withholding; Use by Company

(a) Each participant shall elect to have amounts withheld from his or her
compensation paid by the Company during the option period, at a rate equal to
any whole percentage up to a maximum of 10 percent, or such lesser percentage as
the Board may establish from time to time before an Enrollment Date.
Compensation includes regular salary payments, annual and quarterly performance
bonuses, hire-on bonuses, cash recognition awards, commissions, overtime pay,
shift premiums, and elective contributions by the participant to qualified
employee benefit plans, but excludes all other payments including, without
limitation, long-term disability or workers compensation payments, car
allowances, employee referral bonuses, relocation payments, expense
reimbursements (including but not limited to travel, entertainment, and moving
expenses), salary gross-up payments, and non-cash recognition awards. The
participant shall designate a rate of withholding in his or her enrollment form
and may elect to increase or decrease the rate of contribution effective as of
any Enrollment Date, by delivery to the Company, not later than 15 days before
such Enrollment Date, of a written notice indicating the revised withholding
rate.

(b) Payroll withholdings shall be credited to an account maintained for purposes
of the Plan on behalf of each participant, as soon as administratively feasible
after the withholding occurs. The Company shall be entitled to use the
withholdings for any corporate purpose, shall have no obligation to pay interest
on withholdings to any participant, and shall not be obligated to segregate
withholdings.

(c) Upon disposition of shares acquired by exercise of an option, the
participant shall pay, or make provision adequate to the Company for payment of,
all federal, state, and other tax (and similar) withholdings that the Company
determines, in its discretion, are required due to the disposition, including
any such withholding that the Company determines in its discretion is necessary
to allow the Company to claim tax deductions or other benefits in connection
with the disposition. A participant shall make such similar provisions for
payments that the Company determines, in its discretion, are required due to the
exercise of an option, including such provisions as are necessary to allow the
Company to claim tax deductions or other benefits in connection with the
exercise of the option.

8. Purchase of Shares

(a) On the last trading day of each month immediately preceding a month
containing an Enrollment Date, or on such other days as may be established by
the Board from time to time, prior to an Enrollment Date for all options to be
granted on an Enrollment Date (each a "Purchase Date"), the Company shall apply
the funds then credited to each participant's payroll withholdings account to
the purchase of whole



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shares of Common Stock. The cost to the participant for the shares purchased
under any option shall be not less than 85 percent of the lower of:

(i) the fair market value of the Common Stock on the Enrollment Date for such
option (except that with respect to shares which are sold on a Purchase Date
that were added by an amendment of the Plan between the Enrollment Date for the
option applicable to such Purchase Date and that Purchase Date, it shall be the
fair market value of the Common Stock on the date the Stockholders approved such
amendment); or

(ii) the fair market value of the Common Stock on that Purchase Date.

The "fair market value" of the Common Stock on a date shall be the closing price
of the Common Stock on such date on any established stock exchange or market
system if the Common Stock is traded on such an exchange or market system (and
the largest such exchange or market system if the Common Stock is traded on more
than one), if the Common Stock is not so traded then the mean between the bid
and asked prices for Common Stock on such date as quoted on NASDAQ or reported
in The Wall Street Journal or similar publication if such prices are so quoted
or reported, or the fair market value on such date as determined by the
Administrator if shares of Common Stock are not so traded, quoted, or reported.

(b) Any funds in an amount less than the cost of one share of Common Stock left
in a participant's payroll withholdings account on a Purchase Date shall be
carried forward in such account for application on the next Purchase Date, and
any additional amount shall be distributed to the participant.

(c) If at any Purchase Date, the shares available under the Plan are less than
the number all participants would otherwise be entitled to purchase on such
date, purchases shall be reduced proportionately to eliminate the deficit. Any
funds that cannot be applied to the purchase of shares due to such a reduction
shall be refunded to participants as soon as administratively feasible.

9. Grant of Additional Options

In addition to the options which may be granted under Section 6 of this Plan,
the Board, in its sole discretion, may grant, to each employee satisfying the
eligibility requirements of Section 4, additional options, for a term not to
exceed 27 months and for an identical number of shares. The options granted
hereunder shall be subject to the limitations of Section 6(b)(v) and 6(b)(vi);
provided, however, that immediately before the grant of such additional options,
the limitations imposed thereby upon each recipient's Options subject to payroll
withholdings shall be adjusted to the minimum extent necessary to permit the
grant. The option price shall not be less than 85% of the lower of (i) the fair
market value of the stock on the grant date for such option, or (ii) the fair
market value on the date of exercise. The option will be subject to such
additional terms and conditions, not inconsistent with the terms of the Plan as
interpreted by the Administrator, as may be established from time to time by the
Board.

10. Withdrawal from the Plan

A participant may withdraw from the Plan in full (but not in part) at any time,
effective after written notice thereof is received by the Company. All funds
credited to a participant's payroll withholdings account shall be distributed to
him or her without interest within 60 days after notice of withdrawal is
received by the Company. Any eligible employee who has withdrawn from the Plan
may enroll in the Plan again on any subsequent Enrollment Date in accordance
with the provisions of Section 5.

11. Termination of Employment

Participation in the Plan terminates immediately when a participant ceases to be
employed by the Company for any reason whatsoever (including death or
disability) or otherwise becomes ineligible to participate in the Plan. As soon
as administratively feasible after termination, the Company shall pay to the
participant or his or her beneficiary or legal representative, all amounts
credited to the participant's payroll withholdings account; provided, however,
that if a participant ceases to be employed by the



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Company because of the commencement of employment with a Subsidiary of the
Company that is not a Participating Subsidiary, funds then credited to such
participant's payroll withholdings account shall be applied to the purchase of
whole shares of Common Stock at the next Purchase Date and any funds remaining
after such purchase shall be paid to the participant.

12. Designation of Beneficiary

(a) Each participant may designate one or more beneficiaries in the event of
death and may, in his or her sole discretion, change such designation at any
time. Any such designation shall be effective upon receipt in written form by
the Company and shall control over any disposition by will or otherwise.

(b) As soon as administratively feasible after the death of a participant,
amounts credited to his or her account shall be paid in cash to the designated
beneficiaries or, in the absence of a designation, to the executor,
administrator, or other legal representative of the participant's estate. Such
payment shall relieve the Company of further liability with respect to the Plan
on account of the deceased participant. If more than one beneficiary is
designated, each beneficiary shall receive an equal portion of the account
unless the participant has given express contrary written instructions.

13. Assignment

(a) The rights of a participant under the Plan shall not be assignable by such
participant, by operation of law or otherwise. No participant may create a lien
on any funds, securities, rights, or other property held by the Company for the
account of the participant under the Plan, except to the extent that there has
been a designation of beneficiaries in accordance with the Plan, and except to
the extent permitted by the laws of descent and distribution if beneficiaries
have not been designated.

(b) A participant's right to purchase shares under the Plan shall be exercisable
only during the participant's lifetime and only by him or her, except that a
participant may direct the Company in the enrollment form to issue share
certificates to the participant and his or her spouse in community property, to
the participant jointly with one or more other persons with right of
survivorship, or to certain forms of trusts approved by the Administrator.

14. Administrative Assistance

If the Administrator in its discretion so elects, it may retain a brokerage
firm, bank or other financial institution to assist in the purchase of shares,
delivery of reports, or other administrative aspects of the Plan. If the
Administrator so elects, each participant shall (unless prohibited by the laws
of the nation of his or her employment or residence) be deemed upon enrollment
in the Plan to have authorized the establishment of an account on his or her
behalf at such institution. Shares purchased by a participant under the Plan
shall be held in the account in the name in which the share certificate would
otherwise be issued pursuant to Section 13(b).

15. Costs

All costs and expenses incurred in administering the Plan shall be paid by the
Company, except that any stamp duties or transfer taxes applicable to
participation in the Plan may be charged to the account of such participant by
the Company. Any brokerage fees for the purchase of shares by a participant
shall be paid by the Company, but brokerage fees for the resale of shares by a
participant shall be borne by the participant.

16. Equal Rights and Privileges

All eligible employees shall have equal rights and privileges with respect to
the Plan so that the Plan qualifies as an "employee stock purchase plan" within
the meaning of Section 423 of the Code and the related Treasury Regulations. Any
provision of the Plan which is inconsistent with Section 423 of the Code shall
without further act or amendment by the Company or the Board be reformed to
comply with



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the requirements of Section 423. This Section 16 shall take precedence over all
other provisions of the Plan.

17. Applicable Law

The Plan shall be governed by the substantive laws (excluding the conflict of
laws rules) of the State of California.

18. Modification and Termination

(a) The Board may amend, alter, or terminate the Plan at any time, including
amendments to outstanding options. No amendment shall be effective unless within
12 months after it is adopted by the Board, it is approved by the holders of a
majority of the votes cast at a duly held shareholders' meeting at which a
quorum of the voting power of the Company is represented in person or by proxy,
if such amendment would:

(i) increase the number of shares reserved for purchase under the Plan; or

(ii) require shareholder approval in order to comply with SEC Rule 16b-3.

(b) In the event the Plan is terminated, the Board may elect to terminate all
outstanding options either immediately or upon completion of the purchase of
shares on the next Purchase Date, or may elect to permit options to expire in
accordance with their terms (and participation to continue through such
expiration dates). If the options are terminated prior to expiration, all funds
contributed to the Plan that have not been used to purchase shares shall be
returned to the participants as soon as administratively feasible.

(c) In the event of the sale of all or substantially all of the assets of Sybase
or the Company, or the merger of Sybase or the Company with or into another
corporation, or the dissolution or liquidation of Sybase, a Purchase Date shall
occur on the trading day immediately preceding the date of such event, unless
otherwise provided by the Board in its sole discretion, including provision for
the assumption or substitution of each option under the Plan by the successor or
surviving corporation, or a parent or subsidiary thereof.

19. Rights as an Employee

Nothing in the Plan shall be construed to give any person the right to remain in
the employ of the Company or to affect the Company's right to terminate the
employment of any person at any time with or without cause.

20. Rights as a Shareholder; Delivery of Certificates

Unless otherwise determined by the Board, certificates evidencing shares
purchased on any Purchase Date shall be delivered to participants as soon as
administratively feasible. Participants shall be treated as the owners of their
shares effective as of the Purchase Date.

21. Board and Shareholder Approval

The Plan was approved by the Board of Directors on April 30, 1991, and by the
holders of a majority of the votes cast at a duly held shareholders' meeting on
June 13, 1991, at which a quorum of the voting power of the Company was
represented in person or by proxy. As amended and restated to adopt amendments
not requiring shareholder approval, the Plan was approved by the Board of
Directors on July 30, 1991. The Plan was amended by the Board of Directors on
January 28, 1993, January 27, 1994, January 24, 1995, January 21, 1997, March
13, 1998, March 26, 1999, and February 2, 2000, and such amendments were
approved by the holders of a majority of the votes cast at a duly held
stockholders



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meeting on May 18, 1993, May 24, 1994, May 23, 1995, May 20, 1997, May 27, 1998,
May 27, 1999, and May 25, 2000.

SYBASE, INC.

By: DANIEL R. CARL
Its: Vice President, General
     Counsel and Secretary
 Date: May 25, 2000





[Omitted from this filing is a copy of the 1991 Amended and Restated Foreign
Subsidiary Employee Stock Purchase Plan (as amended February 2, 2000) which in
substance is identical to the foregoing.]



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