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                                                                  EXHIBIT 10.9.1

                               KOMAG INCORPORATED

                 AMENDED AND RESTATED 2002 QUALIFIED STOCK PLAN

                     NOTICE OF GRANT OF STOCK PURCHASE RIGHT

      Unless otherwise defined herein, the terms defined in the Plan shall have
the same defined meanings in this Notice of Grant.

      FIRST NAME, LAST NAME
      ADDRESS
      CITY, STATE ZIP CODE

      You have been granted the right to purchase Common Stock of the Company,
subject to the Company's Repurchase Option and your ongoing status as a
Participant (as described in the Plan and the attached Restricted Stock Purchase
Agreement), as follows:

      Date of Grant

      Price Per Share                             $0.01

      Total Number of Shares Subject              XX,XXX
      to This Stock Purchase Right

      Expiration Date:

      Vesting Schedule:

      YOU MUST ACCEPT THIS STOCK PURCHASE RIGHT BEFORE THE EXPIRATION DATE OR IT
WILL TERMINATE AND YOU WILL HAVE NO FURTHER RIGHT TO PURCHASE THE SHARES. By
your signature and the signature of the Company's representative below, you and
the Company agree that this Stock Purchase Right is granted under and governed
by the terms and conditions of the Amended and Restated 2002 Qualified Stock
Plan and the Restricted Stock Purchase Agreement, attached hereto as Exhibit
A-1, both of which are made a part of this document. You further agree to
execute the attached Restricted Stock Purchase Agreement as a condition to
purchasing any shares under this Stock Purchase Right.

GRANTEE:                                KOMAG INCORPORATED

________________________________        ___________________________________
Signature
________________________________
Print Name

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                                   EXHIBIT A-1

                               KOMAG INCORPORATED

                 AMENDED AND RESTATED 2002 QUALIFIED STOCK PLAN

                       RESTRICTED STOCK PURCHASE AGREEMENT

      Unless otherwise defined herein, the terms defined in the Plan shall have
the same defined meanings in this Restricted Stock Purchase Agreement.

      WHEREAS Purchaser named in the Notice of Grant (the "Purchaser") is a
Participant and Purchaser's continued participation is considered by the Company
to be important for the Company's continued growth; and

      WHEREAS in order to give Purchaser an opportunity to acquire an equity
interest in the Company as an incentive for Purchaser to participate in the
affairs of the Company, the Administrator has granted to Purchaser a Stock
Purchase Right subject to the terms and conditions of the Plan and the Notice of
Grant, which are incorporated herein by reference, and pursuant to this
Restricted Stock Purchase Agreement (the "Agreement").

      NOW THEREFORE, the parties agree as follows:

      1. Sale of Stock. The Company hereby agrees to sell to Purchaser and
Purchaser hereby agrees to purchase shares of the Common Stock (the "Shares"),
at the per Share purchase price and as otherwise described in the Notice of
Grant.

      2. Payment of Purchase Price. The purchase price for the Shares may be
paid by delivery to the Company at the time of execution of this Agreement of
cash, a check, or some combination thereof.

      3. Repurchase Option.

         (a) In the event Purchaser ceases to be a Service Provider for any
or no reason (including death or disability) before all of the Shares are
released from the Company's Repurchase Option (see Section 4), the Company
shall, upon the date of such termination (as reasonably fixed and determined by
the Company) have an irrevocable, exclusive option (the "Repurchase Option") for
a period of sixty (60) days from such date to repurchase up to that number of
shares which constitute the Unreleased Shares (as defined in Section 4) at the
original purchase price per share (the "Repurchase Price"). The Repurchase
Option shall be exercised by the Company by delivering written notice to
Purchaser or Purchaser's executor (with a copy to the Escrow Holder) AND, at the
Company's option, (i) by delivering to Purchaser or Purchaser's executor a check
in the amount of the aggregate Repurchase Price, or (ii) by canceling an amount
of Purchaser's indebtedness to the Company equal to the aggregate Repurchase
Price, or (iii) by a combination of (i) and (ii) so that the combined payment
and cancellation of indebtedness equals the aggregate Repurchase Price. Upon
delivery of such notice and the payment of the aggregate Repurchase Price, the
Company shall become the legal and beneficial owner of the Shares being
repurchased and all rights and interests therein or relating thereto, and the
Company shall have the right to retain and transfer to its own name the number
of Shares being repurchased by the Company.

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            (b) Whenever the Company shall have the right to repurchase Shares
hereunder, the Company may designate and assign one or more employees, officers,
directors or shareholders of the Company or other persons or organizations to
exercise all or a part of the Company's purchase rights under this Agreement and
purchase all or a part of such Shares. If the Fair Market Value of the Shares to
be repurchased on the date of such designation or assignment (the "Repurchase
FMV") exceeds the aggregate Repurchase Price of such Shares, then each such
designee or assignee shall pay the Company cash equal to the difference between
the Repurchase FMV and the aggregate Repurchase Price of such Shares.

      4. Release of Shares From Repurchase Option.

            XXX of the Shares (as determined by the Plan Administrator) shall be
released from the Company's Repurchase Option on each of the first XXX
anniversaries (as determined by the Plan Administrator) of the Date of Grant (as
set forth in the Notice of Grant), subject to Purchaser continuing to be a
Service Provider through such dates.

            (a) Any of the Shares that have not yet been released from the
Repurchase Option are referred to herein as "Unreleased Shares."

            (b) The Shares that have been released from the Repurchase Option
shall be delivered to Purchaser at Purchaser's request as provided in Section 6.

      5. Restriction on Transfer.

            Except for the escrow described in Section 6 or the transfer of the
Shares to the Company or its assignees contemplated by this Agreement, none of
the Shares or any beneficial interest therein shall be transferred, encumbered
or otherwise disposed of in any way until such Shares are released from the
Company's Repurchase Option in accordance with the provisions of this Agreement.
Any distribution or delivery to be made to Purchaser under this Agreement will,
if Purchaser is then deceased, be made to Purchaser's designated beneficiary, or
if no beneficiary survives Purchaser, to the administrator or executor of
Purchaser's estate. Any such transferee must furnish the Company with (a)
written notice of his or her status as transferee, and (b) evidence satisfactory
to the Company to establish the validity of the transfer and compliance with any
laws or regulations pertaining to said transfer.

      6. Escrow of Shares.

            (a) To ensure the availability for delivery of the Unreleased Shares
upon repurchase by the Company pursuant to the Repurchase Option, the Company
shall, upon execution of this Agreement, deliver and deposit with an escrow
holder designated by the Company (the "Escrow Holder") the share certificates
representing the Unreleased Shares. The Unreleased Shares shall be held by the
Escrow Holder until such time as the Company's Repurchase Option expires. The
Shares and stock assignment attached hereto as Exhibit A-2 will be held by the
Escrow Holder until such time as the Company's Repurchase Option expires or the
date Purchaser's status as a Service Provider terminates.

            (b) The Escrow Holder shall not be liable for any act it may do or
omit to do with respect to holding the Unreleased Shares in escrow while acting
in good faith and in the exercise of its judgment.

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            (c) If the Company or any assignee exercises the Repurchase Option
hereunder, the Escrow Holder, upon receipt of written notice of such exercise
from the proposed transferee, shall take all steps necessary to accomplish such
transfer. Purchaser hereby appoints the Escrow Holder with full power of
substitution, as Purchaser's true and lawful attorney-in-fact with irrevocable
power and authority in the name and on behalf of Purchaser to take any action
and execute all documents and instruments, including, without limitation, stock
powers which may be necessary to transfer the certificate or certificates
evidencing such Unreleased Shares to the Company upon such termination.

            (d) When the Repurchase Option has been exercised or expires
unexercised or a portion of the Shares has been released from the Repurchase
Option, upon request the Escrow Holder shall promptly cause a new certificate to
be issued for the released Shares and shall deliver the certificate to the
Company or Purchaser, as the case may be.

            (e) Subject to the terms hereof, Purchaser shall have all the rights
of a shareholder with respect to the Shares while they are held in escrow,
including without limitation, the right to vote the Shares and to receive any
cash dividends declared thereon.

            (f) In the event of any merger, reorganization, consolidation,
recapitalization, separation, liquidation, stock dividend, split-up, share
combination, or other change in the corporate structure of the Company affecting
the Common Stock, the Shares will be increased, reduced or otherwise changed,
and by virtue of any such change Purchaser will in his capacity as owner of
Unreleased Shares that have been awarded to him be entitled to new or additional
or different shares of stock, cash or securities (other than rights or warrants
to purchase securities); such new or additional or different shares, cash or
securities will thereupon be considered to be Unreleased Shares and will be
subject to all of the conditions and restrictions which were applicable to the
Unreleased Shares pursuant to this Agreement. If Purchaser receives rights or
warrants with respect to any Unreleased Shares, such rights or warrants may be
held or exercised by Purchaser, provided that until such exercise any such
rights or warrants and after such exercise any shares or other securities
acquired by the exercise of such rights or warrants will be considered to be
Unreleased Shares and will be subject to all of the conditions and restrictions
which were applicable to the Unreleased Shares pursuant to this Agreement. The
Administrator in its absolute discretion at any time may accelerate the vesting
of all or any portion of such new or additional shares of stock, cash or
securities, rights or warrants to purchase securities or shares or other
securities acquired by the exercise of such rights or warrants.

      7. Legends. The Company may instruct the transfer agent for its Common
Stock to place a legend on the certificates representing the Shares or otherwise
note its records as to the restrictions on transfer set forth in this Agreement.

      8. Withholding of Taxes. The Company will withhold otherwise deliverable
Shares upon release from the Company's Repurchase Option having a Fair Market
Value equal to the minimum amount required to be withheld for the payment of
income, employment and other taxes which the Company determines must be withheld
(the "Withholding Taxes") with respect to such Shares pursuant to such
procedures as the Administrator may specify from time to time. The Company will
not retain fractional Shares to satisfy any portion of the Withholding Taxes.
Accordingly, Purchaser will pay to the Company an amount in cash sufficient to
satisfy the remaining Withholding Taxes due and payable as a result of the
Company not retaining fractional Shares. Should the Company be unable to procure
such cash amounts from Purchaser, Purchaser agrees and acknowledges that
Purchaser is giving the Company

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permission to withhold from Purchaser's paycheck(s) an amount equal to the
remaining Withholding Taxes due and payable as a result of the Company not
retaining fractional Shares.

          9. Tax Consequences. Purchaser has reviewed with Purchaser's own tax
advisors the federal, state, local and foreign tax consequences of this
investment and the transactions contemplated by this Agreement. Purchaser is
relying solely on such advisors and not on any statements or representations of
the Company or any of its agents. Purchaser understands that Purchaser (and not
the Company) shall be responsible for Purchaser's own tax liability that may
arise as a result of the transactions contemplated by this Agreement. Purchaser
understands that Section 83 of the Internal Revenue Code of 1986, as amended
(the "Code"), taxes as ordinary income the difference between the purchase price
for the Shares and the Fair Market Value of the Shares as of the date any
restrictions on the Shares lapse. In this context, "restriction" includes the
right of the Company to buy back the Shares pursuant to the Repurchase Option.
Purchaser understands that Purchaser may elect to be taxed at the time the
Shares are purchased rather than when and as the Repurchase Option expires by
filing an election under Section 83(b) of the Code with the IRS within 30 days
from the date of purchase. The form for making this election is attached as
Exhibit A-3 hereto.

            THE PURCHASER ACKNOWLEDGES THAT IT IS THE PURCHASER'S SOLE
RESPONSIBILITY AND NOT THE COMPANY'S TO FILE TIMELY THE ELECTION UNDER SECTION
83(b), EVEN IF THE PURCHASER REQUESTS THE COMPANY OR ITS REPRESENTATIVES TO MAKE
THIS FILING ON THE PURCHASER'S BEHALF.

          10. General Provisions.

            (a) This Agreement shall be governed by the internal substantive
laws, but not the choice of law rules of California. This Agreement, subject to
the terms and conditions of the Plan and the Notice of Grant, represents the
entire agreement between the parties with respect to the purchase of the Shares
by Purchaser. Subject to Section 16(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 Agreement, the terms and conditions of the Plan shall prevail. Unless
otherwise defined herein, the terms defined in the Plan shall have the same
defined meanings in this Agreement.

            (b) Any notice, demand or request required or permitted to be given
by either the Company or Purchaser pursuant to the terms of this Agreement shall
be in writing and shall be deemed given when delivered personally or deposited
in the U.S. mail, First Class with postage prepaid, and addressed to the parties
at the addresses of the parties set forth at the end of this Agreement or such
other address as a party may request by notifying the other in writing.

                Any notice to the Escrow Holder shall be sent to the Company's
address with a copy to the other party hereto.

            (c) The rights of the Company under this Agreement shall be
transferable to any one or more persons or entities, and all covenants and
agreements hereunder shall inure to the benefit of, and be enforceable by the
Company's successors and assigns. The rights and obligations of Purchaser under
this Agreement may only be assigned with the prior written consent of the
Company.

            (d) Either party's failure to enforce any provision of this
Agreement shall not in any way be construed as a waiver of any such provision,
nor prevent that party from thereafter enforcing any

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other provision of this Agreement. The rights granted both parties hereunder are
cumulative and shall not constitute a waiver of either party's right to assert
any other legal remedy available to it.

            (e) Purchaser agrees upon request to execute any further documents
or instruments necessary or desirable to carry out the purposes or intent of
this Agreement.

            (f) PURCHASER ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES
PURSUANT TO SECTION 4 HEREOF IS EARNED ONLY BY CONTINUING SERVICE AS A
PARTICIPANT AT THE WILL OF THE COMPANY (AND NOT THROUGH THE ACT OF BEING HIRED
OR PURCHASING SHARES HEREUNDER). PURCHASER 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 A PARTICIPANT FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT ALL,
AND SHALL NOT INTERFERE WITH PURCHASER'S RIGHT OR THE COMPANY'S RIGHT TO
TERMINATE PURCHASER'S RELATIONSHIP AS A PARTICIPANT AT ANY TIME, WITH OR WITHOUT
CAUSE.

By Purchaser's signature below, Purchaser represents that he or she is familiar
with the terms and provisions of the Plan, and hereby accepts this Agreement
subject to all of the terms and provisions thereof. Purchaser has reviewed the
Plan and this Agreement in their entirety, has had an opportunity to obtain the
advice of counsel prior to executing this Agreement and fully understands all
provisions of this Agreement. Purchaser agrees to accept as binding, conclusive
and final all decisions or interpretations of the Administrator upon any
questions arising under the Plan or this Agreement. Purchaser further agrees to
notify the Company upon any change in the residence indicated in the Notice of
Grant.

DATED: __________________________

PURCHASER:                                  KOMAG INCORPORATED

___________________________________         ___________________________________
Signature
___________________________________
Print Name

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                                   EXHIBIT A-2

                      ASSIGNMENT SEPARATE FROM CERTIFICATE

      FOR VALUE RECEIVED I, ______________________, hereby sell, assign and
transfer unto Komag Incorporated _____________ shares of the Common Stock of
Komag Incorporated standing in my name of the books of said corporation
represented by Certificate No. _____ herewith and do hereby irrevocably
constitute and appoint ______________________________ to transfer the said stock
on the books of the within named corporation with full power of substitution in
the premises.

      This Stock Assignment may be used only in accordance with the Restricted
Stock Purchase Agreement between Komag Incorporated and the undersigned dated
______________, ____ (the "Agreement").

Dated: _______________, _____                       Signature: _________________

INSTRUCTIONS: Please do not fill in any blanks other than the signature line.
The purpose of this assignment is to enable the Company to exercise its
Repurchase Option as set forth in the Agreement, without requiring additional
signatures on the part of Purchaser.

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                                   EXHIBIT A-3

                          ELECTION UNDER SECTION 83(b)
                      OF THE INTERNAL REVENUE CODE OF 1986

The undersigned taxpayer hereby elects, pursuant to Section 83(b) of the
Internal Revenue Code of 1986, as amended, to include in taxpayer's gross income
for the current taxable year the amount of any compensation taxable to taxpayer
in connection with his or her receipt of the property described below:

1.    The name, address, taxpayer identification number and taxable year of the
      undersigned are as follows:

      NAME:                   TAXPAYER:                 SPOUSE:

      ADDRESS:

      IDENTIFICATION NO.:     TAXPAYER:                 SPOUSE:

      TAXABLE YEAR:

2.    The property with respect to which the election is made is described as
      follows: ________ shares (the "Shares") of the Common Stock of Komag
      Incorporated (the "Company").

3.    The date on which the property was transferred is:,________,____.

4.    The property is subject to the following restrictions:

      The Shares may be repurchased by the Company, or its assignee, upon
      certain events. This right lapses with regard to a portion of the Shares
      based on the continued performance of services by the taxpayer over time.

5.    The fair market value at the time of transfer, determined without regard
      to any restriction other than a restriction which by its terms will never
      lapse, of such property is: $________.

6.    The amount (if any) paid for such property is: $___________.

The undersigned has submitted a copy of this statement to the person for whom
the services were performed in connection with the undersigned's receipt of the
above-described property. The transferee of such property is the person
performing the services in connection with the transfer of said property.

The undersigned understands that the foregoing election may not be revoked
except with the consent of the Commissioner.

Dated: _________________, ____          _______________________________________
                                        Taxpayer

The undersigned spouse of taxpayer joins in this election.

Dated: _________________, ____          _______________________________________
                                        Spouse of Taxpayer