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                                                                    EXHIBIT 10.4

               AMENDED AND RESTATED PRODUCT DEVELOPMENT AGREEMENT

This AMENDED AND RESTATED PRODUCT DEVELOPMENT AGREEMENT, dated as of September
10, 2004, is made and entered into by and between Toshiba Corporation, a
Japanese corporation with a principal place of business at 1-1, Shibaura
1-chome, Minato-ku, Tokyo 105-8001, Japan ("Toshiba"), and SanDisk Corporation,
a Delaware corporation with a principal place of business at 140 Caspian Court,
Sunnyvale, CA 94089, U. S. A. ("SanDisk").

WHEREAS, Toshiba and SanDisk entered into a Product Development Agreement, dated
as of May 9, 2000, which was amended as of April 10, 2002 and which has been
modified by correspondence between SanDisk and Toshiba (collectively, the "Prior
Agreement"); and

WHEREAS, Toshiba and SanDisk desire to amend the Prior Agreement with the effect
of superceding the Prior Agreement from and after the date of this Agreement;

NOW, THEREFORE, the parties agree as follows:

ARTICLE 1. DEFINITIONS

1.1   "Products" shall mean the NAND Flash Memory devices developed hereunder,
      including the NAND Flash Memory devices specified in Exhibit A attached
      hereto, but excluding Flash Memory Controllers.

1.2   "Flash Memory Controller" shall mean any firmware, hardware and/or
      software that is necessary to operate a NAND Flash Memory device.

1.3   "Developed Products" shall mean Products solely developed by either party
      during the term of this Agreement, including solely developed derivatives
      of Jointly Developed Products; provided however, that Developed Products
      shall not include cut-downs of Jointly Developed Products.

1.4   "Jointly Developed Products" shall mean Products jointly developed by
      Toshiba and SanDisk during the term of this Agreement.

1.5   "Toshiba Developed Controller" shall mean a Flash Memory Controller solely
      developed by Toshiba during the term of this Agreement, including solely
      developed derivatives of Jointly Developed Controllers.

1.6   "SanDisk Developed Controller" shall mean a Flash Memory Controller solely
      developed by SanDisk during the term of this Agreement, including solely
      developed derivatives of Jointly Developed Controllers.

1.7   "Jointly Developed Controller" shall mean a Flash Memory Controller
      developed by Toshiba and SanDisk during the term of this Agreement.

1.8   "Development Project" shall mean all development activities undertaken
      pursuant to Article 2.

1.9   "Background Technology" shall mean the Technology which has been or will
      be developed by or for either party independently of the Development
      Projects and

CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY WITH
THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO THE
OMITTED PORTIONS.

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      owned or controlled by such party prior to or during the term of this
      Agreement, and which shall be deemed reasonably necessary for the other
      party to perform the Development Projects. Background Technology may be
      either SanDisk Background Technology or Toshiba Background Technology, as
      the context requires.

1.10  "Technology" shall mean all developments, ideas, inventions, Test
      Technology and other technical information (whether or not patentable)
      relating to Products as well as intellectual property rights relating
      thereto, including trade secrets, copyrights and maskwork rights, but
      specifically excluding Patents.

1.11  "Developed Technology" shall mean Technology solely developed by either
      party in the course of the Development Projects.

1.12  "Jointly Developed Technology" shall mean Technology jointly developed by
      Toshiba and SanDisk in the course of the Development Projects.

1.13  "Test Technology" shall mean all developments, ideas, inventions, test
      programs, test methods, configured and developed hardware and other
      technical information (whether or not patentable) for all stages of
      product manufacture, as well as intellectual property rights relating
      thereto, but specifically excluding Patents, concerning testing of
      Products and Flash Memory Controllers.

1.14  "Controller Technology" shall mean all developments, ideas, inventions and
      technical information (whether or not patentable) relating to Flash Memory
      Controllers and intellectual property rights relating thereto, including,
      but not limited to, trade secrets, copyrights and maskwork rights, but
      specifically excluding Patents.

1.15  "Jointly Developed Controller Technology" shall mean Controller Technology
      developed by Toshiba and SanDisk during the term of this Agreement.

1.16  "Developed Controller Technology" shall mean Controller Technology solely
      developed by either party during the term of this Agreement.

1.17  "SanDisk Controllers" shall mean SanDisk Developed Controllers, Jointly
      Developed Controllers, SanDisk Developed Controller Technology and Jointly
      Developed Controller Technology.

1.18  "SanDisk Products and Technology" shall mean SanDisk Developed Products,
      SanDisk Background Technology, SanDisk Developed Technology and SanDisk
      Controllers.

1.19  "Toshiba Products and Technology" shall mean Toshiba Developed Products,
      Toshiba Background Technology, Toshiba Developed Technology, Toshiba
      Developed Controller Technology and Toshiba Developed Controllers.

1.20  "Joint Products and Technology" shall mean Jointly Developed Products and
      Jointly Developed Technology.

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1.21  "Patents" shall mean all classes of types of patents, utility models
      (excluding design patents) and any applications therefor in all countries
      of the world, which are, now or hereafter, owned or controlled by either
      party hereto.

1.22  "Jointly Developed Patents" shall mean Patents which arise out of the
      inventions jointly made by the employees of Toshiba or SanDisk in the
      course of the Development Projects.

1.23  "Effective Date" shall be September 10, 2004.

1.24  "Agreement" means this Amended and Restated Product Development Agreement
      together with any Exhibits, Schedules, Appendices and Attachments hereto
      and Appendix A.

1.24  "Master Agreement" shall mean that certain Flash Partners Master
      Agreement, dated as of the date hereof, by and among Toshiba, SanDisk and
      SanDisk International, a company organized under the laws of the Cayman
      Islands.

1.25  "Appendix A" shall mean the Definitions, Rules of Construction and
      Documentary Conventions, attached as Appendix A to the Master Agreement.

1.26  "Direct R&D Effective Date" shall mean May 9, 2000.

ARTICLE 2. DEVELOPMENT

2.1   Except as expressed in the Common R&D Agreement, each party agrees to
      undertake at Toshiba's or SanDisk's facilities (such facility or
      facilities to be determined by the Coordinating Committee prior to
      commencement of the applicable Development Project) the Development
      Projects specified in Exhibit A in accordance with a development schedule
      and activity allocations to be determined by the Coordinating Committee.
      During the term of this Agreement, the parties will use reasonable efforts
      to continually identify and pursue joint development of new products and
      Exhibit A may be amended from time to time, in accordance with the
      approval of the Coordinating Committee, to reflect such new Development
      Projects.

2.2   Each party shall, from time to time during the term of this Agreement and
      to the extent reasonably necessary to perform the Development Projects,
      provide the other party with technical information relating to its
      Background Technology.

2.3   Each party shall, from time to time during the term of this Agreement,
      provide the other party with technical information relating to Jointly
      Developed Technology and Jointly Developed Controller Technology.

2.4   A party that is in possession of Jointly Developed Technology, Jointly
      Developed Controller Technology or other technical information, including
      the items specified in Exhibit C, shall, upon request of the other party
      made at any time during the term of this Agreement or for a period of one
      year thereafter, promptly deliver to the other party copies of such
      information as requested. When requested by either party, such exchange of
      information, shall include test flow conditions and related know-how.

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2.5   During the term of this Agreement, upon request by either party and
      subject to the availability of the other party's engineers, the other
      party shall (i) delegate its qualified engineers to advise and consult
      with such requesting party at the requesting party's facilities or (ii)
      receive qualified engineers of the requesting party to train and advise at
      its own facilities. The details of such delegation or reception of the
      engineers shall be decided by the Coordinating Committee as described in
      Article 3.

2.6   This Agreement shall not encompass or include products or technology
      developed jointly or solely by the parties, utilizing or based on Toshiba
      NOR flash technology or other Toshiba non-NAND Flash technologies, or
      SanDisk NOR flash technology or other SanDisk non-NAND flash technologies.

2.7   Either party may propose to disclose (the "proposing party") Jointly
      Developed Controller Technology to any Qualified Design House under a
      written agreement of confidentiality and non-use, for a period of
      restriction generally to be discussed and agreed upon by the Coordinating
      Committee, but if not so discussed or agreed upon, then for a period of at
      least seven years, for the purpose of engaging such Qualified Design House
      to design a solely developed Flash Memory Controller for the account of
      the proposing party to be manufactured and sold by the proposing party.
      Prior to making such disclosure to a Qualified Design House, the proposing
      party shall give the other party to this Agreement (the "reviewing party")
      the opportunity to jointly develop such product with the proposing party.
      The opportunity should be presented in detail at a meeting of the
      Coordinating Committee and the reviewing party will be given a reasonable
      amount of time to consider the proposal. If the reviewing party accepts
      the opportunity to enter into such joint development, the proposing party
      shall not make the disclosure to the Qualified Design House. For the
      purpose of this section, "Qualified Design House" shall mean a company
      which offers services to design devices similar to Flash Memory
      Controllers but which does not make or sell flash memory devices or flash
      cards.

2.8   Each of Toshiba and SanDisk agree to provide to the other party certain
      information relating to product development, including the information set
      forth in Exhibit D attached hereto

ARTICLE 3. COORDINATING COMMITTEE

3.1   Immediately after the Effective Date, the parties shall jointly establish
      the "Coordinating Committee" which shall be comprised of six (6)
      representatives; three (3) of which shall be appointed by Toshiba and
      three (3) of which shall be appointed by SanDisk, which appointments shall
      have been approved by each of the parties; provided that such approval
      shall not be unreasonably withheld.

3.2   The Coordinating Committee shall be responsible for:

      (a)   Determining new Products and Flash Memory Controllers to be jointly
            developed, including product design and manufacturing
            specifications. All Product development projects, including Flash
            Memory Controller development projects, and projects considered by
            either party for sole development, shall be disclosed to the
            Coordinating Committee prior to the start of development;

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      (b)   Reviewing the progress of the Development Projects against the
            development schedule and evaluating the Development Projects;

      (c)   Discussing necessary changes to the scope or the schedules of the
            Development Projects and actions to be taken;

      (d)   Resolving any differences in opinions between the parties which may
            arise during the course of the Development Projects;

      (e)   Allocation of wafer processing costs as specified in Article 5;

      (f)   Discussing inventorship of patents conceived by the parties as a
            result of any joint development activity hereunder; and

      (g)   Any other matters as agreed upon by both parties.

      All decisions by the Coordinating Committee, including any decision to
      jointly develop Products or Flash Memory Controllers, shall be made
      unanimously and shall be set forth in writing. If any matter is not
      determined by unanimous consent of the Coordinating Committee, such matter
      shall be referred to Management Committee (as defined in the Master
      Agreement) for its final decision. In connection with discussing
      inventorship of patents pursuant to Section 3.2(f), the parties agree to
      notify the Coordinating Committee as soon as possible, but not later than
      three months after such party's knowledge of the filing date of the
      particular patent.

3.3   The Coordinating Committee shall have periodical meetings which shall be
      led by the Technical Coordinator of both parties on a quarterly basis, or
      at such other intervals, alternatively in the United States and in Japan
      or such other places as mutually agreed upon by the Technical Coordinators
      of each party. Either party may invite other of its employees to attend
      such meetings.

ARTICLE 4. TECHNICAL COORDINATORS

Each party shall designate from time to time its Technical Coordinator from its
three members of the Coordinating Committee to be appointed in accordance with
Section 3.1. The Technical Coordinator shall be responsible for supervision of
transmittal and receipt of technical information hereunder, coordinating the
site visits by engineers and coordination of the training and consultation to be
performed hereunder. The incumbent Technical Coordinators for each party are as
follows:

For Toshiba: [To be determined]

For SanDisk: Khandker Quader

ARTICLE 5. COST

Each party shall bear all costs and expenses incurred by such party in
performing the Development Projects which will include the salaries of its
engineers involved in joint development projects hereunder. Notwithstanding the
foregoing, in order to balance each party's cost for Jointly Developed Products
and Jointly Developed Flash Memory Controllers, SanDisk shall share Toshiba's
direct costs of processing certain wafers to be

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made for the purpose of such Product design verification (including mask costs)
in the amounts set forth in Exhibit B. If either party believes there are
significant additional costs (beyond direct costs) that should be shared (i.e.
other material costs such as subcontractors fees for packaging and analysis),
the Parties will discuss in good faith if any appropriate amount of such
additional costs is to be shared between the Parties. Similarly, Toshiba shall
share the direct costs of processing certain wafers to be made for the purpose
of Flash Memory Controller verification (including mask costs) and other
material costs relating thereto, such as subcontractor fees for packaging and
analysis, in a manner as determined by the Coordinating Committee but
conceptually similar to the nature of the expenses shared by SanDisk for
Products.

ARTICLE 6. OWNERSHIP

6.1   Toshiba Products and Technology shall be and remain the exclusive property
      of Toshiba, subject to the license granted in accordance with Section 7.1.
      From time to time, upon request of SanDisk, Toshiba shall offer SanDisk,
      based upon reasonable terms, a non-exclusive, worldwide, non-transferable
      license, without right to sublicense, to develop, have developed, make,
      have made, use, sell, modify and otherwise dispose of all or a portion of
      the Toshiba Products and Technology.

6.2   Toshiba Patents shall be and remain the exclusive property of Toshiba,
      subject to the licenses granted in accordance with the Patent Cross
      License Agreement between SanDisk Corporation and Toshiba Corporation, as
      amended from time to time, the "Patent Agreement").

6.3   SanDisk Products and Technology shall be and remain the exclusive property
      of SanDisk, subject to the licenses granted in accordance with Sections
      7.2 and 7.3 hereof. From time to time, upon request of Toshiba, SanDisk
      shall offer Toshiba, based upon reasonable terms, a non-exclusive,
      worldwide, non-transferable license, without right to sublicense, to
      develop, have developed, make, have made, use, sell, modify and otherwise
      dispose of all or a portion of the SanDisk Products and Technology.

6.4   SanDisk Patents shall be and remain the exclusive property of SanDisk,
      subject to the licenses granted in accordance with the Patent Agreement.

6.5   Any right, title and interest in and to Joint Products and Technology
      shall be jointly owned by Toshiba and SanDisk. With the exception that
      neither party may sublicense or transfer Joint Products and Technology
      without the prior written consent of the other party, Toshiba and SanDisk
      each has the right to use, fully exploit, disclose or otherwise dispose of
      such Joint Products and Technology for any purpose without consent of nor
      accounting to the other party.

6.6   Any right, title and interest in and to Jointly Developed Patents shall be
      jointly owned by Toshiba and SanDisk. Each party shall be free to use such
      Jointly Developed Patents for any purpose and shall have the right to
      grant non-exclusive licenses to any third party without the consent of nor
      accounting to the other party. Both parties shall promptly agree on which
      of them shall file and prosecute the first patent application and which
      countries' corresponding applications shall be filed and by whom. All
      expenses incurred in obtaining and maintaining such patents shall be
      shared equally by the parties; provided that if one party elects not to
      seek or maintain such patents in

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      any particular country or not to share equally in the expense thereof, the
      other party shall have the right to seek or maintain such patents in said
      country at its own expense and shall have full control over the
      prosecution and maintenance thereof even though title to any patent
      issuing thereon shall be joint. The party electing not to seek or maintain
      such patents shall give the other party any necessary assistance required
      for the preparation and prosecution of such patents filed or maintained by
      the other party. Jointly Developed Patents shall not be considered
      "SanDisk Licensed Patents" or "Toshiba Licensed Patents" as defined in the
      Patent Agreement.

ARTICLE 7. LICENSE

7.1   Subject to the terms and conditions of this Agreement, Toshiba hereby
      grants to SanDisk a non-exclusive, non-transferable, worldwide and
      royalty-free license, without the right to sublicense, to use Toshiba
      Background Technology provided to SanDisk hereunder to develop, have
      developed, make, have made, use, sell, modify and otherwise dispose of
      Products, SanDisk Controllers and any other controller products designed
      by or for SanDisk.

7.2   Subject to the terms and conditions of this Agreement, SanDisk hereby
      grants to Toshiba a non-exclusive, non-transferable, worldwide and
      royalty-free license, without the right to sublicense, to use SanDisk
      Background Technology provided to Toshiba hereunder to develop, have
      developed, make, have made, use, sell, modify and otherwise dispose of
      Products, Toshiba Developed Controllers and other controller products not
      designed or used for file storage.

7.3   Subject to the terms and conditions of this Agreement, SanDisk hereby
      grants to Toshiba a non-exclusive, non-transferable, worldwide and
      royalty-free license, without the right to sublicense, to make, have made,
      use, sell, modify and otherwise dispose of any Jointly Developed
      Controllers.

7.4   It is understood that SanDisk has the right to use, fully exploit,
      disclose, sublicense, transfer or otherwise dispose of SanDisk Controllers
      and any other controller product designed by or for SanDisk without
      consent from or accounting to Toshiba, even if such SanDisk Controllers or
      other controller products incorporate any Toshiba Background Technology.

ARTICLE 8. WARRANTY

8.1   Toshiba and SanDisk each provides to the other party its Background and
      Developed Technology on an "as-is" basis only, and neither makes any
      warranty or representation with respect to the Background Technology or
      Developed Technology for any purpose.

8.2   Nothing contained in this Agreement shall be construed as:

      (a)   a warranty or representation that the manufacture, use, sale or
            other disposal of semiconductor products by the other party using
            any technical information received under this Agreement will be free
            from infringement of patents or any other intellectual property
            rights of third party;

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      (b)   conferring to the other party any right to use in advertising,
            publicity or otherwise any trademark, trade name or names, any
            contraction, abbreviation or simulations thereof of either party;

      (c)   conferring to the other party, by implication, estoppel or
            otherwise, any license or other right except for the licenses and
            rights expressly granted hereunder; or

      (d)   an obligation to furnish any technical information or know-how
            except as otherwise specifically provided herein.

ARTICLE 9. LIMITATION OF LIABILITY

Neither party shall be responsible to the other party in respect of any action
taken or reliance upon any information furnished to the other party under this
Agreement, except to the extent of any breach of the warranties or agreements
set forth in this Agreement. IN NO EVENT SHALL EITHER PARTY BE LIABLE TO THE
OTHER PARTY FOR ANY SPECIAL, CONSEQUENTIAL, INCIDENTAL OR INDIRECT DAMAGE OF ANY
KIND, (INCLUDING LOSS OF PROFIT OR DATA) WHETHER OR NOT ADVISED OF THE
POSSIBILITY OF SUCH LOSS.

ARTICLE 10. CONFIDENTIALITY

10.1  As used in this Agreement, the term "Confidential Information" shall mean
      any information disclosed by one party to other party pursuant to this
      Agreement which is in written, graphic, machine readable or other tangible
      form and is marked Confidential, Proprietary or in some other manner to
      indicate its confidential nature. Confidential Information may also
      include oral information disclosed by one party to the other party
      pursuant to this Agreement; provided that such information is designated
      in a manner to indicate its confidential nature at the time of disclosure
      and reduced to a written summary by the disclosing party within thirty
      (30) days after its oral disclosure.

10.2  During the [***] period following receipt of such information, the
      receiving party shall keep, and cause its Subsidiaries, its sublicensees
      and subcontractors who have access to Confidential Information as
      permitted in this Agreement to keep any Confidential Information,
      including but not limited to Background Technology and Developed
      Technology provided by the disclosing party hereunder, in strict
      confidence, and shall not disclose such Confidential Information to any
      third party without the prior written consent of the disclosing party. The
      receiving party shall maintain the Confidential Information with at least
      the same degree of care that the receiving party uses to protect its own
      strictly confidential information, but no less than a reasonable degree of
      care under the circumstances. Further, the receiving party shall not use
      the Confidential Information for any purpose other than for the
      Development Projects, except as otherwise provided herein.

10.3  Each party shall not disclose the terms and conditions of this Agreement
      to any third party without the prior written consent of the other party.

10.4  The confidentiality obligation set forth in Articles 10.2 and 10.3 above
      shall not apply to any information which:

[***] INDICATES THAT CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION PURSUANT TO RULE 24B-2. CONFIDENTIAL TREATMENT
HAS BEEN REQUESTED WITH RESPECT TO THE OMITTED PORTIONS.

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      (a)   is already known by the receiving party at the time of disclosure;

      (b)   is or becomes publicly known through no fault of the receiving
            party;

      (c)   is rightfully received by the receiving party from a third party
            without any restriction on disclosure;

      (d)   is independently developed by the receiving party;

      (e)   is disclosed with the prior written consent of the disclosing party
            hereto; or

      (f)   is disclosed pursuant to applicable laws, regulations or court
            order, provided that the receiving party shall give the disclosing
            party prompt notice of such request so that the disclosing party has
            an opportunity to defend, limit or protect such disclosure.

10.5  Each party understands that disclosure or dissemination of the other
      party's Confidential Information, specifically Toshiba Background
      Technology provided to SanDisk in connection with the Development
      Projects, not expressly authorized hereunder would cause irreparable
      injury to such other party, for which monetary damages would not be an
      adequate remedy and said other party shall be entitled to equitable relief
      in addition to any remedies the other party may have hereunder or at law.
      In the event SanDisk is to enter into any joint development work with any
      third party, SanDisk warrants that Toshiba Background Technology provided
      to SanDisk in connection with the Development Projects shall neither be
      used for such joint development work nor be disclosed to any third party
      unless expressly otherwise provided hereunder.

10.6  The Technical Coordinator of each party shall ensure that the other
      party's Technical Coordinator is informed of and receives in sufficient
      detail and completeness the Background and Developed Technology that is
      exchanged under Article 2. Each Technical Coordinator shall also monitor
      within their company the distribution of Confidential Information received
      from the other party only to those who have a need to know and, further,
      to assist in preventing the unauthorized disclosure of the Confidential
      Information to personnel within the company who do not have a need to
      know, or to third parties. The Technical Coordinator for each party shall
      maintain pertinent records and the like, and acknowledge the receipt from
      the other party of all Confidential Information.

ARTICLE 11. TERM AND TERMINATION

11.1  This Agreement shall become effective on the Direct R&D Effective Date and
      continue in full force and effect until later of the termination of the
      FVC-Japan Master Agreement or the Master Agreement, unless earlier
      terminated as hereinafter provided. The term of this Agreement may be
      extended by mutual agreement of both parties.

11.2  If either party fails to perform or breaches any of its material
      obligations under this Agreement, then, upon sixty (60) days advanced
      written notice specifying such failure or breach, the non-defaulting party
      shall have the right to terminate this Agreement forthwith, unless the
      failure or breach specified in the notice has been cured during

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      the sixty (60) day period. Termination of this Agreement pursuant to this
      Section 11.2 shall not relieve the breaching party from any liability
      arising from any breach of this Agreement and such termination shall be
      without prejudice to any other rights and remedies of the non-breaching
      party provided at law or in equity, in addition to the rights and remedies
      set forth in this Agreement.

11.3  Either party shall have the right to terminate this Agreement by giving
      written notice to the other party upon the occurrence of any of the
      following events:

      (a)   the filing by the other party of a voluntary petition in bankruptcy
            or insolvency;

      (b)   any adjudication that such other party is bankrupt or insolvent;

      (c)   the filing by such other party of any legal action or document
            seeking reorganization, readjustment or arrangement of its business
            under any law relating to bankruptcy or insolvency;

      (d)   the appointment of a receiver for all or substantially all of the
            property of such other party; or

      (e)   the making by such other party of any assignment of whole or
            substantial assets for the benefit of creditors.

      This Agreement shall terminate on the thirtieth (30th) day after such
      notice of termination is given.

11.4  In the event of termination or expiration of this Agreement, the rights
      and licenses granted to each party specified in Article 7 shall survive
      such termination or expiration, except that if this Agreement is
      terminated by either party for any of the events specified in Sections
      11.2 and 11.3, then the licenses granted to the defaulting party or the
      non-terminating party, as the case may be, shall thereupon terminate. The
      provisions of Articles 6, 8, 9, 10, 11 and 12 shall survive any
      termination or expiration of this Agreement.

ARTICLE 12. GENERAL PROVISIONS

12.1  Neither party is required to disclose any information of which disclosure
      is prohibited by laws of the country of such party.

12.2  In the event that the parties will, after the Effective Date, make an
      announcement regarding this transaction and their business relationship,
      such announcement shall be in a mutually agreeable form and at a mutually
      agreeable time; provided that any information to be disclosed and/or
      announced by either party shall be identified through consultation with
      the other party and be agreed upon between the parties before the
      disclosure and announcement.

12.3  Neither party shall export or re-export, directly or indirectly, any
      technical information disclosed hereunder or direct product thereof to any
      destination prohibited or restricted by the export control regulations of
      Japan and the United

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      States, including the U.S. Export Administration Regulations, without the
      prior authorization from the appropriate governmental authorities. SanDisk
      hereby certifies that SanDisk will not use technical information supplied
      by Toshiba hereunder for any purpose to develop or manufacture nuclear,
      chemical, biological weapons or missiles (hereafter "weapons of mass
      destruction"). SanDisk further certifies that it will not sell any
      products manufactured using Toshiba's technical information to any party
      if it knows that the end-user of the products will use them for the
      development and/or manufacture of the weapons of mass destruction.

12.4  The rules of construction and documentary conventions set forth in
      Appendix A to this Agreement shall apply to, and are hereby incorporated
      in, this Agreement.

                             [signatures next page]

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      IN WITNESS WHEREOF, each of the parties hereto have caused this Agreement
to be executed in duplicate, as of the date first written above, by their
respective duly authorized officers or representatives.

       Toshiba Corporation                              SanDisk Corporation

By: /s/ Masashi Muromachi                          By: /s/ Eli Harari
    ----------------------                             -------------------------
Name:  Masashi Muromachi                           Name:  Eli Harari
Title: President and CEO                           Title: President and CEO
       Semiconductor Company
       Corporate Vice President

[signature page to Amended and Restated Product Development Agreement]

<PAGE>

                                    Exhibit A

      Jointly Developed Products and Jointly Developed Flash Memory Controllers

1.    256 M       NAND Flash Memory

2.    512 M       NAND Flash Memory

3.    1 G         NAND Flash Memory

4.    2 G         NAND Flash Memory

5.    4 G         NAND Flash Memory

6.    [***]

Note 1: The Coordinating Committee will determine (i) the best process
technology to utilize for all products to be jointly developed pursuant to this
Agreement (e.g. 0.16 micron, 0.13 micron, 90 nanometer and smaller sizes), (ii)
whether such products shall use [***] or [***] and (iii) detail product
specifications, such as, but not limited to, voltage operating range [***].

Note 2: The Coordinating Committee shall be responsible for determining
development responsibilities of each party with respect to jointly developed
products.

Note 3: All Products and Flash Memory Controllers jointly developed hereunder
shall include the development of wafer test products. A "wafer test product" is
a test system used to test semiconductor wafers.

[***] INDICATES THAT CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION PURSUANT TO RULE 24B-2. CONFIDENTIAL TREATMENT
HAS BEEN REQUESTED WITH RESPECT TO THE OMITTED PORTIONS.

<PAGE>

                                    Exhibit B

                       SHARING OF WAFER PROCESSING COSTS -
       (For Jointly Developed Products and Jointly Developed Controllers)

                           Jointly Developed Products

            [***]

                          Jointly Developed Controllers

      (1) Wafer processing cost associated with Jointly Developed Controllers
      will be shared by the parties as determined by the Coordinating Committee
      in accordance with Section 3.2.

      Note 1: All costs charged pursuant to this Exhibit B are direct costs and
      have been referred to by the parties as Direct R&D charges. Original
      back-up information and financial detail of all such charges shall be made
      available to the party paying the shared expense, and all such charges are
      subject to financial audit by the external auditors of the party paying
      the charge. The party receiving payment shall cooperate with all
      reasonable requests to view and make copies of financial back-up and
      financial detail material associated with the charges.

      Note 2: Payments specified above shall be made within sixty (60) days
      after receipt of invoice issued at the end of each calendar half year.

[***] INDICATES THAT CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION PURSUANT TO RULE 24B-2. CONFIDENTIAL TREATMENT
HAS BEEN REQUESTED WITH RESPECT TO THE OMITTED PORTIONS.

<PAGE>

                                    Exhibit C

[***]

[***] INDICATES THAT CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION PURSUANT TO RULE 24B-2. CONFIDENTIAL TREATMENT
HAS BEEN REQUESTED WITH RESPECT TO THE OMITTED PORTIONS.

<PAGE>

                                    Exhibit D

                              Information Exchange

[***]

[***] INDICATES THAT CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION PURSUANT TO RULE 24B-2. CONFIDENTIAL TREATMENT
HAS BEEN REQUESTED WITH RESPECT TO THE OMITTED PORTIONS.