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                                                                    EXHIBIT 10.2

                               ALTERA CORPORATION

                        1987 EMPLOYEE STOCK PURCHASE PLAN

                     (as amended and restated October, 2001)

        The following constitute the provisions of the 1987 Employee Stock
Purchase Plan, as amended and restated October, 2001, of Altera Corporation.

        1. Purpose. The purpose of the Plan is to provide employees of the
Company and its Designated Subsidiaries with an opportunity to purchase Common
Stock of the Company through accumulated payroll deductions. It is the intention
of the Company to have the Plan qualify as an "Employee Stock Purchase Plan"
under Section 423 of the Internal Revenue Code. The provisions of the Plan,
accordingly, shall be construed so as to extend and limit participation in a
uniform and nondiscriminatory basis consistent with the requirements of Section
423.

        2. Definitions.

               (a) "Administrator" shall mean the Board or any Committee
designated by the Board to administer the plan pursuant to Section 15 of the
Plan.

               (b) "Board" shall mean the Board of Directors of the Company.

               (c) "Change of Control" shall mean the occurrence of any of the
following events:

                         (i) Any "person" (as such term is used in Sections
13(d) and 14(d) of the Exchange Act) becomes the "beneficial owner" (as defined
in Rule 13d-3 of the Exchange Act), directly or indirectly, of securities of the
Company representing fifty percent (50%) or more of the total voting power
represented by the Company's then outstanding voting securities; or

                         (ii) The consummation of the sale or disposition by the
Company of all or substantially all of the Company's assets; or

                         (iii) The consummation of a merger or consolidation of
the Company, with any other corporation, other than a merger or consolidation
that would result in the voting securities of the Company outstanding
immediately prior thereto continuing to represent (either by remaining
outstanding or by being converted into voting securities of the surviving entity
or its parent) at least fifty percent (50%) of the total voting power
represented by the voting securities of the Company, or such surviving entity or
its parent outstanding immediately after such merger or consolidation.

                         (iv) A change in the composition of the Board, as a
result of which fewer than a majority of the Directors are Incumbent Directors.
"Incumbent Directors" shall mean Directors who either (A) are Directors of the
Company, as applicable, as of the date hereof, or (B) are elected, or nominated
for election, to the Board with the affirmative votes of at least a

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majority of those Directors whose election or nomination was not in connection
with any transaction described in subsections (i), (ii) or (iii) or in
connection with an actual or threatened proxy contest relating to the election
of directors of the Company.

               (d) "Code" shall mean the Internal Revenue Code of 1986, as
amended.

               (e) "Committee" means a committee of the Board appointed by the
Board in accordance with Section 15 hereof.

               (f) "Common Stock" shall mean the common stock of the Company.

               (g) "Company" shall mean Altera Corporation, a Delaware
corporation.

               (h) "Compensation" shall mean all base straight time gross
earnings, sales commissions and sales incentives, but exclusive of payments for
overtime, shift premiums, other incentive payments, bonuses or other
compensation.

               (i) "Designated Subsidiary" shall mean any Subsidiary selected by
the Administrator as eligible to participate in the Plan.

               (j) "Eligible Employee" shall mean any individual who is a common
law employee of the Company or any Designated Subsidiary and whose customary
employment with the Company or Designated Subsidiary is at least twenty (20)
hours per week and more than five (5) months in any calendar year. For purposes
of the Plan, the employment relationship shall be treated as continuing intact
while the individual is on sick leave or other leave of absence approved by the
Company. Where the period of leave exceeds 90 days and the individual's right to
reemployment is not guaranteed either by statute or by contract, the individual
shall be deemed to have withdrawn from the Plan on the 91st day of such leave.

               (k) "Exercise Date" shall mean the Trading Day on or before April
30th and October 31st of each year.

               (l) "Fair Market Value" shall mean, as of any date, the value of
Common Stock determined as follows:

                         (i) If the Common Stock is listed on any established
stock exchange or a national market system, including without limitation the
Nasdaq National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market,
its Fair Market Value shall be the closing sales price for such stock (or the
closing bid, if no sales were reported) as quoted on such exchange or system on
the date of determination, as reported in The Wall Street Journal or such other
source as the Board deems reliable;

                         (ii) If the Common Stock is regularly quoted by a
recognized securities dealer but selling prices are not reported, its Fair
Market Value shall be the mean of the closing bid and asked prices for the
Common Stock on the date of determination, as reported in The Wall Street
Journal or such other source as the Board deems reliable;

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                         (iii) In the absence of an established market for the
Common Stock, the Fair Market Value thereof shall be determined in good faith by
the Board; or

                         (iv) For purposes of the Offering Date of the first
Offering Period under the Plan, the Fair Market Value shall be the initial price
to the public as set forth in the final prospectus included within the
registration statement in Form S-1 filed with the Securities and Exchange
Commission for the initial public offering of the Company's Common Stock (the
"Registration Statement").

               (m) "Offering Date" shall mean the first Trading Day of each
Offering Period.

               (n) "Offering Periods" shall mean the periods of approximately
twelve (12) months during which an option granted pursuant to the Plan may be
exercised, usually commencing on the first Trading Day on or after May 1st and
November 1st of each year and terminating on the Trading Day on or before April
30th and October 31st. The duration and timing of Offering Periods may be
changed pursuant to Section 4 of this Plan.

               (o) "Plan" shall mean this Employee Stock Purchase Plan.

               (p) "Purchase Period" shall mean the approximately six (6) month
period commencing on one Exercise Date and ending with the next Exercise Date,
except that the first Purchase Period of any Offering Period shall commence on
the Offering Date and end with the next Exercise Date.

               (q) "Purchase Price" shall mean 85% of the Fair Market Value of a
share of Common Stock on the Offering Date or on the Exercise Date, whichever is
lower; provided however, that the Purchase Price may be adjusted by the
Administrator pursuant to Section 20.

               (r) "Subsidiary" shall mean a "subsidiary corporation," whether
now or hereafter existing, as defined in Section 424(f) of the Code.

               (s) "Trading Day" shall mean a day on which national stock
exchanges and the Nasdaq System are open for trading.

        3. Eligibility.

               (a) Subsequent Offering Periods. Any Eligible Employee on a given
Offering Date shall be eligible to participate in the Plan.

               (b) Limitations. Any provisions of the Plan to the contrary
notwithstanding, no Eligible Employee shall be granted an option under the Plan
(i) to the extent that, immediately after the grant, such Eligible Employee (or
any other person whose stock would be attributed to such Eligible Employee
pursuant to Section 424(d) of the Code) would own capital stock of the Company
and/or hold outstanding options to purchase such stock possessing five percent
(5%) or more of the total combined voting power or value of all classes of the
capital stock of the Company or of any Subsidiary, or (ii) to the extent that
his or her rights to purchase stock under all employee stock purchase plans of
the Company and its subsidiaries accrues at a rate that

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exceeds Twenty-Five Thousand Dollars ($25,000) worth of stock (determined at the
Fair Market Value of the shares at the time such option is granted) for each
calendar year in which such option is outstanding at any time.

        4. Offering Periods. The Plan shall be implemented by consecutive,
overlapping Offering Periods with a new Offering Period commencing on the first
Trading Day on or after May 1st and November 1st each year, or on such other
date as the Board shall determine, and continuing thereafter until terminated in
accordance with Section 21 hereof. The Board shall have the power to change the
duration of Offering Periods (including the commencement dates thereof) with
respect to future offerings without shareholder approval if such change is
announced prior to the scheduled beginning of the first Offering Period to be
affected thereafter.

        5. Subsequent Offering Periods. An Eligible Employee may become a
participant in the Plan by completing a subscription agreement authorizing
payroll deductions in the form of Exhibit A to this Plan and filing it with the
Company's Stock Administration Department prior to the applicable Offering Date.

        6. Payroll Deductions.

               (a) At the time a participant files his or her subscription
agreement, he or she shall elect to have payroll deductions made on each pay day
during the Offering Period in an amount not exceeding 10% of the Compensation
that he or she receives on each pay day during the Offering Period; provided,
however, that should a pay day occur on an Exercise Date, a participant shall
have the payroll deductions made on such day applied to his or her account under
the new Offering Period or Purchase Period, as the case may be. A participant's
subscription agreement shall remain in effect for successive Offering Periods
unless terminated as provided in Section 11 hereof.

               (b) Payroll deductions for a participant shall commence on the
first payday following the Offering Date and shall end on the last payday in the
Offering Period to which such authorization is applicable, unless sooner
terminated by the participant as provided in Section 11 hereof.

               (c) All payroll deductions made for a participant shall be
credited to his or her account under the Plan and shall be withheld in whole
percentages only. A participant may not make any additional payments into such
account.

               (d) A participant may discontinue his or her participation in the
Plan as provided in Section 11 hereof, or decrease the rate of his or her
payroll deductions during the Offering Period by completing or filing with the
Company a new subscription agreement authorizing a change in payroll deduction
rate. A participant may increase his or her rate of payroll deductions only for
a subsequent Offering Period in which he or she is scheduled to participate and
may not increase his or her rate of payroll deductions during an outstanding
Offering Period in which such participant is currently participating. The
Administrator may, in its discretion, limit the nature and/or number of
participation rate changes during any Offering Period. Any decrease in rate
shall be effective fifteen (15) days following the Company's receipt of the
notification.

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               (e) Notwithstanding the foregoing, to the extent necessary to
comply with Section 423(b)(8) of the Code and Section 3(b) hereof, the
Administrator may decrease a participant's payroll deductions to zero percent
(0%) at any time during a Purchase Period. Payroll deductions shall recommence
at the rate provided in such participant's subscription agreement at the
beginning of the first Purchase Period that is scheduled to end in the following
calendar year, unless terminated by the participant as provided in Section 11
hereof.

               (f) At the time the option is exercised, in whole or in part, or
at the time some or all of the Company's Common Stock issued under the Plan is
disposed of, the participant must make adequate provision for the Company's
federal, state, or other tax withholding obligations, if any, which arise upon
the exercise of the option or the disposition of the Common Stock. At any time,
the Company may, but shall not be obligated to, withhold from the participant's
compensation the amount necessary for the Company to meet applicable withholding
obligations, including any withholding required to make available to the Company
any tax deductions or benefits attributable to sale or early disposition of
Common Stock by the Eligible Employee.

        7. Grant of Option. On the Offering Date of each Offering Period, each
Eligible Employee participating in such Offering Period shall be granted an
option to purchase on each Exercise Date during such Offering Period (at the
applicable Purchase Price) up to a number of shares of the Company's Common
Stock determined by dividing such Eligible Employee's payroll deductions
accumulated prior to such Exercise Date and retained in the Participant's
account as of the Exercise Date by the applicable Purchase Price; provided that
in no event shall an Eligible Employee be permitted to purchase during each
Purchase Period more than 10,000 shares of the Company's Common Stock (subject
to any adjustment pursuant to Section 20 hereof), and provided further that such
purchase shall be subject to the limitations set forth in Section 3(b) and other
sections of the Plan that may limit such number. The Eligible Employee may
accept the grant of such option by turning in a completed Subscription Agreement
to the Company on or prior to an Offering Date. The Administrator may, for
future Offering Periods, increase or decrease, in its absolute discretion, the
maximum number of shares of the Company's Common Stock an Eligible Employee may
purchase during each Purchase Period of such Offering Period. Exercise of the
option shall occur as provided in Section 9 hereof, unless the participant has
withdrawn pursuant to Section 11 hereof. The option shall expire on the last day
of the Offering Period.

        8. Automatic Transfer to Low Price Offering Period. To the extent
permitted by any applicable laws, regulations, or stock exchange rules, if the
Fair Market Value of the Common Stock on any Exercise Date in an Offering Period
is lower than the Fair Market Value of the Common Stock on the Offering Date of
such Offering Period, then all participants in such Offering Period shall be
automatically withdrawn from such Offering Period immediately after the exercise
of their option on such Exercise Date and automatically re-enrolled in the
immediately following Offering Period.

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        9. Exercise of Option.

               (a) Unless a participant withdraws from the Plan as provided in
Section 11 hereof, his or her option for the purchase of shares shall be
exercised automatically on the Exercise Date, and the maximum number of full
shares subject to option shall be purchased for such participant at the
applicable Purchase Price with the accumulated payroll deductions in his or her
account. No fractional shares shall be purchased; any payroll deductions
accumulated in a participant's account that are not sufficient to purchase a
full share shall be retained in the participant's account for the subsequent
Purchase Period or Offering Period, subject to earlier withdrawal by the
participant as provided in Section 11 hereof. Any other funds left over in a
participant's account after the Exercise Date shall be returned to the
participant. During a participant's lifetime, a participant's option to purchase
shares hereunder is exercisable only by him or her.

               (b)If the Administrator determines that, on a given Exercise
Date, the number of shares with respect to which options are to be exercised may
exceed (i) the number of shares of Common Stock that were available for sale
under the Plan on the Offering Date of the applicable Offering Period, or (ii)
the number of shares available for sale under the Plan on such Exercise Date,
the Administrator may in its sole discretion (1) provide that the Company shall
make a pro rata allocation of the shares of Common Stock available for purchase
on such Offering Date or Exercise Date, as applicable, in as uniform a manner as
shall be practicable and as it shall determine in its sole discretion to be
equitable among all participants exercising options to purchase Common Stock on
such Exercise Date, and continue all Offering Periods then in effect, or (2)
provide that the Company shall make a pro rata allocation of the shares
available for purchase on such Offering Date or Exercise Date, as applicable, in
as uniform a manner as shall be practicable and as it shall determine in its
sole discretion to be equitable among all participants exercising options to
purchase Common Stock on such Exercise Date, and terminate any or all Offering
Periods then in effect pursuant to Section 21 hereof. The Company may make pro
rata allocation of the shares available on the Offering Date of any applicable
Offering Period pursuant to the preceding sentence, notwithstanding any
authorization of additional shares for issuance under the Plan by the Company's
shareholders subsequent to such Offering Date.

               10. Delivery. As soon as reasonably practicable after each
Exercise Date on which a purchase of shares occurs, the Company shall arrange
the delivery to each participant the shares purchased upon exercise of his or
her option in a form determined by the Administrator.

        11. Withdrawal.

               (a) A participant may withdraw all but not less than all the
payroll deductions credited to his or her account and not yet used to exercise
his or her option under the Plan at any time by giving written notice to the
Company. All of the participant's payroll deductions credited to his or her
account shall be paid to such participant promptly after receipt of notice of
withdrawal and such participant's option for the Offering Period shall be
automatically terminated, and no further payroll deductions for the purchase of
shares shall be made for such Offering Period. If a participant withdraws from
an Offering Period, payroll deductions shall not

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resume at the beginning of the succeeding Offering Period unless the participant
delivers to the Company a new Subscription Agreement.

               (b) A participant's withdrawal from an Offering Period shall not
have any effect upon his or her eligibility to participate in any similar plan
that may hereafter be adopted by the Company or in succeeding Offering Periods
that commence after the termination of the Offering Period from which the
participant withdraws.

        12. Termination of Employment. In the event a participant ceases to be
an Eligible Employee prior to the Exercise Date of the Offering Period in
question for any reason, including retirement or death, the payroll deductions
credited to the participant's account will be returned to the participant, or in
the case of the participant's death, to the person or persons entitled thereto
pursuant to Section 16 of the Plan, and the participant's option will
automatically terminate.

        13. Interest. No interest shall accrue on the payroll deductions of a
participant in the Plan.

        14. Stock.

               (a) Subject to adjustment upon changes in capitalization of the
Company as provided in Section 20 hereof, the maximum number of shares of the
Company's Common Stock that shall be made available for sale under the Plan
shall be 14,200,000.

               (b) Until the shares are issued (as evidenced by the appropriate
entry on the books of the Company or of a duly authorized transfer agent of the
Company), a participant shall only have the rights of an unsecured creditor with
respect to such shares, and no right to vote or receive dividends or any other
rights as a stockholder shall exist with respect to such shares.

               (c) Shares to be delivered to a participant under the Plan shall
be registered in the name of the participant or in the name of the participant
and his or her spouse.

        15. Administration. The Administrator shall administer the Plan and
shall have full and exclusive discretionary authority to construe, interpret and
apply the terms of the Plan, to determine eligibility and to adjudicate all
disputed claims filed under the Plan. Every finding, decision and determination
made by the Administrator shall, to the full extent permitted by law, be final
and binding upon all parties.

        16. Designation of Beneficiary.

               (a) Unless otherwise prohibited by applicable law, a participant
may file a written designation of a beneficiary who is to receive any shares and
cash, if any, from the participant's account under the Plan in the event of such
participant's death subsequent to an Exercise Date on which the option is
exercised but prior to delivery to such participant of such shares and cash. In
addition, a participant may file a written designation of a beneficiary who is
to receive any cash from the participant's account under the Plan in the event
of such participant's death prior to

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exercise of the option. If a participant is married and the designated
beneficiary is not the spouse, spousal consent shall be required for such
designation to be effective.

               (b) Such designation of beneficiary may be changed by the
participant at any time by written notice. In the event of the death of a
participant and in the absence of a beneficiary validly designated under the
Plan who is living at the time of such participant's death, the Company shall
deliver such shares and/or cash to the executor or administrator of the estate
of the participant, or if no such executor or administrator has been appointed
(to the knowledge of the Company), the Company, in its discretion, may deliver
such shares and/or cash to the spouse or to any one or more dependents or
relatives of the participant, or if no spouse, dependent or relative is known to
the Company, then to such other person as the Company may designate.

               (c) All beneficiary designations shall be in such form and manner
as the Administrator may designate from time to time.

        17. Transferability. Neither payroll deductions credited to a
participant's account nor any rights with regard to the exercise of an option or
to receive shares under the Plan may be assigned, transferred, pledged or
otherwise disposed of in any way (other than by will, the laws of descent and
distribution, or as provided in Section 16 hereof) by the participant. Any such
attempt at assignment, transfer, pledge or other disposition shall be without
effect, except that the Company may treat such act as an election to withdraw
funds from an Offering Period in accordance with Section 11 hereof.

        18. Use of Funds. All payroll deductions received or held by the Company
under the Plan may be used by the Company for any corporate purpose, and the
Company shall not be obligated to segregate such payroll deductions. Until
shares are issued, participants shall only have the rights of an unsecured
creditor.

        19. Reports. Individual accounts shall be maintained for each
participant in the Plan. Statements of account shall be given to participating
Eligible Employees at least annually, which statements shall set forth the
amounts of payroll deductions, the Purchase Price, the number of shares
purchased and the remaining cash balance, if any.

        20. Adjustments Upon Changes in Capitalization, Dissolution,
Liquidation, Merger or Change of Control.

               (a) Changes in Capitalization. Subject to any required action by
the shareholders of the Company, the maximum number of shares of the Company's
Common Stock that shall be made available for sale under the Plan, the maximum
number of shares each participant may purchase each Purchase Period (pursuant to
Section 7), as well as the price per share and the number of shares of Common
Stock covered by each option under the Plan that have not yet been exercised,
shall be proportionately adjusted for any increase or decrease in the number of
issued shares of Common Stock resulting from a stock split, reverse stock split,
stock dividend, combination or reclassification of the Common Stock, or any
other change in the number of shares of Common Stock effected without receipt of
consideration by the Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to

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have been "effected without receipt of consideration." Such adjustment shall be
made by the Administrator, whose determination in that respect shall be final,
binding and conclusive. Except as expressly provided herein, no issuance by the
Company of shares of stock of any class, or securities convertible into shares
of stock of any class, shall affect, and no adjustment by reason thereof shall
be made with respect to, the number or price of shares of Common Stock subject
to an option.

               (b) Dissolution or Liquidation. In the event of the proposed
dissolution or liquidation of the Company, the Offering Period then in progress
shall be shortened by setting a new Exercise Date (the "New Exercise Date"), and
shall terminate immediately prior to the consummation of such proposed
dissolution or liquidation, unless provided otherwise by the Administrator. The
New Exercise Date shall be before the date of the Company's proposed dissolution
or liquidation. The Administrator shall notify each participant in writing, at
least ten (10) business days prior to the New Exercise Date, that the Exercise
Date for the participant's option has been changed to the New Exercise Date and
that the participant's option shall be exercised automatically on the New
Exercise Date, unless prior to such date the participant has withdrawn from the
Offering Period as provided in Section 11 hereof.

               (c) Merger or Change of Control. In the event of a merger or
Change of Control, each outstanding option shall be assumed or an equivalent
option substituted by the successor corporation or a Parent or Subsidiary of the
successor corporation. In the event that the successor corporation refuses to
assume or substitute for the option, any Purchase Periods then in progress shall
be shortened by setting a New Exercise Date and any Offering Periods then in
progress shall end on the New Exercise Date. The New Exercise Date shall be
before the date of the Company's proposed merger or Change of Control. The
Administrator shall notify each participant in writing, at least ten (10)
business days prior to the New Exercise Date, that the Exercise Date for the
participant's option has been changed to the New Exercise Date and that the
participant's option shall be exercised automatically on the New Exercise Date,
unless prior to such date the participant has withdrawn from the Offering Period
as provided in Section 11 hereof.

        21. Amendment or Termination.

               (a) The Administrator may at any time and for any reason
terminate or amend the Plan. Except as otherwise provided in the Plan, no such
termination can affect options previously granted, provided that an Offering
Period may be terminated by the Administrator on any Exercise Date if the
Administrator determines that the termination of the Offering Period or the Plan
is in the best interests of the Company and its shareholders. Except as provided
in Section 20 and this Section 21 hereof, no amendment may make any change in
any option theretofore granted which adversely affects the rights of any
participant. To the extent necessary to comply with Section 423 of the Code (or
any successor rule or provision or any other applicable law, regulation or stock
exchange rule), the Company shall obtain shareholder approval in such a manner
and to such a degree as required.

               (b) Without shareholder consent and without regard to whether any
participant rights may be considered to have been "adversely affected," the
Administrator shall be entitled to

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change the Offering Periods, limit the frequency and/or number of changes in the
amount withheld during an Offering Period, establish the exchange ratio
applicable to amounts withheld in a currency other than U.S. dollars, permit
payroll withholding in excess of the amount designated by a participant in order
to adjust for delays or mistakes in the Company's processing of properly
completed withholding elections, establish reasonable waiting and adjustment
periods and/or accounting and crediting procedures to ensure that amounts
applied toward the purchase of Common Stock for each participant properly
correspond with amounts withheld from the participant's Compensation, and
establish such other limitations or procedures as the Administrator determines
in its sole discretion advisable which are consistent with the Plan.

               (c) In the event the Administrator determines that the ongoing
operation of the Plan may result in unfavorable financial accounting
consequences, the Board may, in its discretion and to the extent necessary or
desirable, modify or amend the Plan to reduce or eliminate such accounting
consequence including, but not limited to:

                         (i) increasing the Purchase Price for any Offering
Period, including an Offering Period underway at the time of the change in
Purchase Price;

                         (ii) shortening any Offering Period so that Offering
Period ends on a new Exercise Date, including an Offering Period underway at the
time of the Board action; and

                         (iii) allocating shares.

Such modifications or amendments shall not require stockholder approval or the
consent of any Plan participants.

        22. Notices. All notices or other communications by a participant to the
Company under or in connection with the Plan shall be deemed to have been duly
given when received in the form and manner specified by the Company at the
location, or by the person, designated by the Company for the receipt thereof.

        23. Conditions Upon Issuance of Shares. Shares shall not be issued with
respect to an option unless the exercise of such option and the issuance and
delivery of such shares pursuant thereto comply with all applicable provisions
of law, domestic or foreign, including, without limitation, the Securities Act
of 1933, as amended, the Securities Exchange Act of 1934, as amended, the rules
and regulations promulgated thereunder, and the requirements of any stock
exchange upon which the shares may then be listed, and shall be further subject
to the approval of counsel for the Company with respect to such compliance.

               As a condition to the exercise of an option, the Company may
require the person exercising such option to represent and warrant at the time
of any such exercise that the shares are being purchased only for investment and
without any present intention to sell or distribute such shares if, in the
opinion of counsel for the Company, such a representation is required by any of
the aforementioned applicable provisions of law.

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        24. Term of Plan. The Plan shall become effective upon the earlier to
occur of its adoption by the Board of Directors or its approval by the
shareholders of the Company. It shall continue in effect until terminated under
Section 21 hereof.

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                               ALTERA CORPORATION
                        1987 EMPLOYEE STOCK PURCHASE PLAN
                             SUBSCRIPTION AGREEMENT

                        OFFERING DATE: _________________

================================================================================

          ___ ORIGINAL APPLICATION ___CHANGE IN PAYROLL DEDUCTION RATE

                         ___ CHANGE OF BENEFICIARY(IES)

================================================================================

All capitalized terms not defined herein shall have the meanings ascribed to
them in the "Altera Corporation 1987 Employee Stock Purchase Plan".

1.  I, ______________________________________, employee # __________ hereby
    elect to participate in the Altera Corporation 1987 Employee Stock Purchase
    Plan, as amended (the "Stock Purchase Plan"), and subscribe to purchase
    shares of the Company's Common Stock, par value $0.001 per share, in
    accordance with this Subscription Agreement and the Stock Purchase Plan.

2.  Employee Location (please check one): Corporate __ Domestic Field __
    International __ For domestic field and international employees, please list
    the state or country your office is located in. Office Location
    _______________________

3.  I hereby authorize payroll deductions from each paycheck in an amount equal
    to __________% (not to exceed 10%) of my Compensation on each payday during
    the Offering Period in accordance with the Stock Purchase Plan.

4.  I understand that said payroll deductions shall be accumulated for the
    purchase of shares of Common Stock, par value $0.001 per share, at the
    applicable purchase price determined in accordance with the Stock Purchase
    Plan. I further understand that, except as otherwise set forth in the Stock
    Purchase Plan, shares will be purchased for me automatically on the Exercise
    Date of the Offering Period unless I otherwise withdraw from the Stock
    Purchase Plan by giving written notice to the Company for such purpose.

5.  I have received a copy of the Company's most recent prospectus, which
    describes the Stock Purchase Plan, and a copy of the complete "Altera
    Corporation 1987 Employee Stock Purchase Plan". I understand that my
    participation in the Stock Purchase Plan is in all respects subject to the
    terms of the Plan.

6.  I HAVE NOT elected the DIRECT DEPOSIT PROGRAM. Please issue my shares under
    the following name(s)______________________________________________________.

7.  I HAVE elected the DIRECT DEPOSIT PROGRAM. My broker of choice is:

               __ Smith Barney     __ Charles Schwab

    My account number is ______________________________
    (If selection of the Direct Deposit Program is indicated, account number
    must be included)

8.  I hereby agree to be bound by the terms of the Stock Purchase Plan. The
    effectiveness of this Subscription Agreement is dependent upon my
    eligibility to participate in the Stock Purchase Plan.

__________________________________                      ________________________
Employee Signature                                      Date

<PAGE>

              ALTERA CORPORATION 1987 EMPLOYEE STOCK PURCHASE PLAN
                             BENEFICIARY DESIGNATION

In the event of my death, I hereby designate the following as my
beneficiary(ies) to receive all payments and shares due me under the Stock
Purchase Plan:

PRIMARY (PLEASE PRINT)

================================================================================

NAME: (PLEASE PRINT)

        ________________________________________________________________
        (FIRST)       (MIDDLE)              (LAST)        (RELATIONSHIP)

        ________________________________________________________________
        (SOCIAL SECURITY NUMBER, IF APPLICABLE)

        ________________________________________________________________
        (STREET ADDRESS)

        ________________________________________________________________
        (CITY)                      (STATE)                      (ZIP)

================================================================================

SECONDARY (PLEASE PRINT)

================================================================================

NAME: (PLEASE PRINT)

        ________________________________________________________________
        (FIRST)       (MIDDLE)              (LAST)        (RELATIONSHIP)

        ________________________________________________________________
        (SOCIAL SECURITY NUMBER, IF APPLICABLE)

        ________________________________________________________________
        (STREET ADDRESS)

        ________________________________________________________________
        (CITY)                      (STATE)                      (ZIP)

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        ________________________________________________________________
        (FIRST)       (MIDDLE)              (LAST)        (RELATIONSHIP)

        ________________________________________________________________
        (SOCIAL SECURITY NUMBER, IF APPLICABLE)

        ________________________________________________________________
        (STREET ADDRESS)

        ________________________________________________________________
        (CITY)                      (STATE)                      (ZIP)

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__________________________________                      ________________________
Employee Signature                                      Date<PAGE>
                                                                   EXHIBIT 10.15

                         FORM OF STOCK OPTION AGREEMENT

        Unless otherwise defined herein, the terms defined in Altera's 1996
Stock Option Plan (the "Plan") shall have the same defined meanings in this
Option Agreement ("Agreement").

        You have been granted an option to purchase Common Stock of the Company,
subject to the terms and conditions of the Plan, the Notice of Stock Option
Grant ("Notice of Grant"), and this Agreement.

        1. Vesting Rights. Subject to the applicable provisions of the Plan and
this Agreement, this Option may be exercised, in whole or in part, in accordance
with the schedule set forth in the Notice of Grant.

        2. Termination Period.

           (a) General Rule. Except as provided below, this Option may be
exercised for thirty (30) days after termination of Optionee's employment or
consulting relationship with the Company. In the event of Optionee's change in
status from Employee to Consultant or Consultant to Employee, this Option
Agreement shall remain in effect. In no event shall this Option be exercised
later than the Term/Expiration Date set forth in the Notice of Grant.

           (b) Death; Disability. Upon the termination of Optionee's employment
or consulting relationship with the Company by reason of his or her death or
Disability, this Option may be exercised for six (6) months after such
termination, provided that in no event shall this Option be exercised later than
the Term/Expiration Date set forth in the Notice of Grant.

        3. Grant of Option. The Plan Administrator of the Company hereby grants
to the Optionee named in the Notice of Grant (the "Optionee") an option (the
"Option") to purchase the number of Shares, as set forth in the Notice of Grant,
at the exercise price per share set forth in the Notice of Grant (the "Exercise
Price"), subject to the terms and conditions of the Plan, which is incorporated
herein by reference. Subject to Section 14(c) of the Plan, in the event of a
conflict between the terms and conditions of the Plan and the terms and
conditions of this Option Agreement, the terms and conditions of the Plan shall
prevail.

               If designated in the Notice of Grant as an Incentive Stock Option
("ISO"), this Option is intended to qualify as an Incentive Stock Option under
Section 422 of the Code. However, if this Option is intended to be an Incentive
Stock Option, to the extent that it exceeds the $100,000 rule of Code Section
422(d) it shall be treated as a Nonstatutory Stock Option ("NSO").

        4. Exercise of Option.

           (a) Right to Exercise. This Option is exercisable during its term in
accordance with the Vesting Schedule set out in the Notice of Grant and the
applicable provisions of the Plan and this Option Agreement. In the event of
Optionee's death, disability or other termination of Optionee's employment or
consulting relationship, the exercisability of the Option is governed by the
applicable provisions of the Plan and this Option Agreement.

                                       2
<PAGE>

           (b) Cessation of Vesting Due to Employee Schedule Change. In the
event an Employee, who is regularly scheduled to work twenty (20) hours or more
per week, voluntarily chooses (i.e., other than for reasons protected by law) to
reduce his or her work schedule with the Company to fewer than twenty (20) hours
per week, the Shares subject to the Option shall cease to vest during the period
of time in which the Employee regularly maintains such a schedule. Shares
subject to the Option shall begin to vest again once the Employee is regularly
scheduled to work twenty (20) hours or more per week. The Administrator shall
make the determination as to when vesting shall cease or begin again. The
Administrator may, in its discretion, permit Shares subject to the Option to
continue to vest during the time that such Employee is regularly scheduled to
work fewer than (20) hours per week.

           (c) Method of Exercise. This Option is exercisable by delivery of an
exercise notice (the "Exercise Notice"), which shall state the election to
exercise the Option, the number of Shares in respect of which the Option is
being exercised (the "Exercised Shares"), and such other representations and
agreements as may be required by the Company pursuant to the provisions of the
Plan. The Exercise Notice shall be delivered in person, by mail, via electronic
mail or facsimile or by other authorized method to the Secretary of the Company
or other person designated by the Company. The Exercise Notice shall be
accompanied by payment of the aggregate Exercise Price as to all Exercised
Shares. This Option shall be deemed to be exercised upon receipt by the Company
of such fully executed Exercise Notice accompanied by such aggregate Exercise
Price.

           No Shares shall be issued pursuant to the exercise of this Option
unless such issuance and exercise complies with all relevant provisions of law
and the requirements of any stock exchange or quotation service upon which the
Shares are then listed. Assuming such compliance, for income tax purposes the
Exercised Shares shall be considered transferred to the Optionee on the date the
Option is exercised with respect to such Exercised Shares.

        5. Method of Payment. Payment of the aggregate Exercise Price shall be
by any of the following, or a combination thereof, at the election of the
Optionee:

           (a) cash; or

           (b) check; or

           (c) broker assisted cashless exercise; or

           (d) surrender of other Shares which (i) in the case of Shares
acquired upon exercise of an option, have been owned by the Optionee for more
than six (6) months on the date of surrender, and (ii) have a Fair Market Value
on the date of surrender equal to the aggregate Exercise Price of the Exercised
Shares; or

           (e) other method authorized by the Company.

        6. Non-Transferability of Option. This Option may not be transferred in
any manner otherwise than by will or by the laws of descent or distribution and
may be exercised during the lifetime of Optionee only by the Optionee. The terms
of the Plan and this Option Agreement

                                       3
<PAGE>

shall be binding upon the executors, administrators, heirs, successors and
assigns of the Optionee.

        7. Term of Option. This Option may be exercised only within the term set
out in the Notice of Grant, and may be exercised during such term only in
accordance with the Plan and the terms of this Option Agreement.

        8. U.S. Tax Consequences. For Optionees subject to U.S. income tax, some
of the federal and California tax consequences relating to this Option, as of
the date of this Option, are set forth below. All other Optionees should consult
a tax advisor for tax consequences relating to this Option in their respective
jurisdiction. THIS SUMMARY IS NECESSARILY INCOMPLETE, AND THE TAX LAWS AND
REGULATIONS ARE SUBJECT TO CHANGE. THE OPTIONEE SHOULD CONSULT A TAX ADVISER
BEFORE EXERCISING THIS OPTION OR DISPOSING OF THE SHARES.

           (a) Exercising the Option.

               (i) Nonstatutory Stock Option. The Optionee may incur regular
federal income tax and California income tax liability upon exercise of a NSO.
The Optionee will be treated as having received compensation income (taxable at
ordinary income tax rates) equal to the excess, if any, of the Fair Market Value
of the Exercised Shares on the date of exercise over their aggregate Exercise
Price. If the Optionee is an Employee or a former Employee, the Company will be
required to withhold from his or her compensation or collect from Optionee and
pay to the applicable taxing authorities an amount in cash equal to a percentage
of this compensation income at the time of exercise, and may refuse to honor the
exercise and refuse to deliver Shares if such withholding amounts are not
delivered at the time of exercise.

               (ii) Incentive Stock Option. If this Option qualifies as an ISO,
the Optionee will have no regular federal income tax or California income tax
liability upon its exercise, although the excess, if any, of the Fair Market
Value of the Exercised Shares on the date of exercise over their aggregate
Exercise Price will be treated as an adjustment to alternative minimum taxable
income for federal tax purposes and may subject the Optionee to alternative
minimum tax in the year of exercise. In the event that the Optionee undergoes a
change of status from Employee to Consultant, any Incentive Stock Option of the
Optionee that remains unexercised shall cease to qualify as an Incentive Stock
Option and will be treated for tax purposes as a Nonstatutory Stock Option on
the ninety-first (91st) day following such change of status.

           (b) Disposition of Shares.

               (i) NSO. If the Optionee holds NSO Shares for at least one year,
any gain realized on disposition of the Shares will be treated as long-term
capital gain for federal income tax purposes.

               (ii) ISO. If the Optionee holds ISO Shares for at least one year
after exercise and two years after the grant date, any gain realized on
disposition of the Shares will be treated as long-term capital gain for federal
income tax purposes. If the Optionee disposes of

                                       4
<PAGE>

ISO Shares within one year after exercise or two years after the grant date, any
gain realized on such disposition will be treated as compensation income
(taxable at ordinary income rates) to the extent of the excess, if any, of the
lesser of (A) the difference between the Fair Market Value of the Shares
acquired on the date of exercise and the aggregate Exercise Price, or (B) the
difference between the sale price of such Shares and the aggregate Exercise
Price.

           (c) Notice of Disqualifying Disposition of ISO Shares. If the
Optionee sells or otherwise disposes of any of the Shares acquired pursuant to
an ISO on or before the later of (i) two years after the grant date, or (ii) one
year after the exercise date, the Optionee shall immediately notify the Company
in writing of such disposition. The Optionee agrees that he or she may be
subject to income tax withholding by the Company on the compensation income
recognized from such early disposition of ISO Shares by payment in cash or out
of the current earnings paid to the Optionee.

        9. Entire Agreement; Governing Law. The Plan is incorporated herein by
reference. The Plan, the Notice of Grant, and this Option Agreement constitute
the entire agreement of the parties with respect to the subject matter hereof
and supersede in their entirety all prior undertakings and agreements of the
Company and Optionee with respect to the subject matter hereof, and may not be
modified adversely to the Optionee's interest except by means of a writing
signed by the Company and Optionee. This agreement is governed by California law
except for that body of law pertaining to conflict of laws.

        10. NO GUARANTEE OF EMPLOYMENT. OPTIONEE UNDERSTANDS AND AGREES THAT HIS
OR HER EMPLOYMENT WITH THE COMPANY OR ITS SUBSIDIARIES IS FOR AN UNSPECIFIED
DURATION AND CONSTITUTES "AT-WILL" EMPLOYMENT. OPTIONEE ACKNOWLEDGES AND AGREES
THAT THE VESTING OF SHARES PURSUANT TO THE VESTING SCHEDULE HEREOF IS EARNED
ONLY BY CONTINUING SERVICE AS AN EMPLOYEE OR CONSULTANT AT THE WILL OF THE
COMPANY OR ITS SUBSIDIARY (AND NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED
AN OPTION OR PURCHASING SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND
AGREES THAT THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE
VESTING SCHEDULE SET FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED
PROMISE OF CONTINUED ENGAGEMENT AS AN EMPLOYEE OR CONSULTANT FOR THE VESTING
PERIOD, FOR ANY PERIOD, OR AT ALL, AND SHALL NOT INTERFERE WITH OPTIONEE'S RIGHT
OR THE COMPANY'S AND/OR SUBSIDIARY'S RIGHT TO TERMINATE OPTIONEE'S EMPLOYMENT OR
CONSULTING RELATIONSHIP AT ANY TIME, WITH OR WITHOUT CAUSE.

        By your signature and the signature of the Company's representative on
the Notice of Grant, you and the Company agree that this Option is granted under
and governed by the terms and conditions of the Plan, the Notice of Grant, and
this Option Agreement. Optionee has reviewed the Plan, the Notice of Grant, and
this Option Agreement in their entirety, has had an opportunity to obtain the
advice of counsel prior to executing the Notice of Grant, and fully understands
all provisions of the Plan, the Notice of Grant, and Option Agreement. Optionee
hereby agrees to accept as binding, conclusive and final all decisions or
interpretations of the Administrator upon any questions relating to the Plan,
the Notice of Grant, and the Option

                                       5
<PAGE>

Agreement. Optionee further agrees to notify the Company upon any change in the
residence address indicated on the Notice of Grant.

                                       6

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