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     As filed with the Securities and Exchange Commission on August 3, 2001
                                                           Registration No. 333-

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                            -------------------------

                                    FORM S-8

                             REGISTRATION STATEMENT

                                      UNDER

                           THE SECURITIES ACT OF 1933

                               PDF SOLUTIONS, INC.
             (Exact Name of Registrant as Specified in Its Charter)

                 Delaware                                       25-1701361
    (State or Other Jurisdiction of                          (I.R.S. Employer
     Incorporation or Organization)                       Identification Number)

  333 West San Carlos Street, Suite 700
          San Jose, California                                     95110
(Address of Principal Executive Offices)                         (Zip Code)

                             1996 STOCK OPTION PLAN
                                 1997 STOCK PLAN
                                 2001 STOCK PLAN
                        2001 EMPLOYEE STOCK PURCHASE PLAN

                            -------------------------

                            (Full Title of the Plans)

                                JOHN K. KIBARIAN
                      President and Chief Executive Officer
                               PDF Solutions, Inc.
                      333 West San Carlos Street, Suite 700
                           San Jose, California 95110
                     (Name and Address of Agent for Service)

                                 (408) 280-7900
          (Telephone Number, Including Area Code, of Agent for Service)

                                   Copies to:

                                Peter Cohn, Esq.
                       Orrick, Herrington & Sutcliffe LLP
                                 1020 Marsh Road
                          Menlo Park, California 94025
                                 (650) 614-7400

                         CALCULATION OF REGISTRATION FEE



==================================================================================================================================
                                                                                        Proposed        Proposed
                                                                                         Maximum        Maximum
                                                                                        Offering        Aggregate       Amount of
                        Title of Securities to be                       Amount To Be      Price         Offering      Registration
                               Registered                              Registered (1)  Per Share(2)       Price           Fee
- ----------------------------------------------------------------------------------------------------------------------------------
                                                                                                          
Common Stock, $0.00015 par value (1996 Stock Option Plan)                   5,560        $ 0.06       $       324      $     1
- ----------------------------------------------------------------------------------------------------------------------------------
Common Stock, $0.00015 par value (1997 Stock Plan)                      1,188,425        $ 9.23       $10,969,163      $ 2,742.29
- ----------------------------------------------------------------------------------------------------------------------------------
Common Stock, $0.00015 par value (2001 Stock Plan)                      3,000,000        $14.32       $42,960,000      $10,740
- ----------------------------------------------------------------------------------------------------------------------------------
Common Stock, $0.00015 par value (2001 Employee Stock Purchase Plan)      300,000        $14.32       $ 4,290,000      $ 1,072.50
- ----------------------------------------------------------------------------------------------------------------------------------
Total                                                                   4,493,985                                      $14,555.79
==================================================================================================================================




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(1) This Registration Statement shall also cover any additional shares of Common
Stock which become issuable under any of the Plans by reason of any stock
dividend, stock split, recapitalization or other similar transaction effected
without the Registrant's receipt of consideration which results in an increase
in the number of the Registrant's outstanding shares of Common Stock.

(2) The Proposed Maximum Offering Price Per Share represents a weighted average
of the following estimates calculated in accordance with Rule 457(h) under the
Securities Act of 1933, as amended (the "Securities Act"). With respect to 5,560
shares subject to outstanding options to purchase Common Stock under the 1996
Stock Option Plan described above, the Proposed Maximum Offering Price Per Share
is equal to the weighted average exercise price of $0.06 per share pursuant to
Rule 457(h) under the Securities Act. With respect to 1,188,425 shares subject
to outstanding options to purchase Common Stock under the 1997 Stock Plan
described above, the Proposed Maximum Offering Price Per Share is equal to the
weighted average exercise price of $9.23 per share pursuant to Rule 457(h) under
the Securities Act. With respect to 3,300,000 shares of Common Stock available
for future grant under the 2001 Stock Plan and the 2001 Employee Stock Purchase
Plan, the estimated Proposed Maximum Offering Price Per Share was calculated
pursuant to Rules 457(c) and 457(h) under the Securities Act on the basis of
$14.32 per share, the average of the high and low price of the Common Stock on
the Nasdaq National Market on July 27, 2001.



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                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

ITEM 1. PLAN INFORMATION *

ITEM 2. REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION *

        * Information required by Part I to be contained in the Section 10(a)
        prospectus is omitted from this Registration Statement in accordance
        with Rule 428 under the Securities Act of 1933, as amended (the
        "Securities Act"), and the Note to Part I of Form S-8.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE

PDF Solutions, Inc. (the "Registrant") hereby incorporates by reference into
this Registration Statement the following documents previously filed with the
Securities and Exchange Commission (the "Commission"):

                (a) The Registrant's prospectus filed with the Commission
        pursuant to Rule 424(b) promulgated under the Securities Act filed with
        the SEC on July 27, 2001 (File No. 333-43192), in which there is set
        forth the audited financial statements for the Registrant's fiscal year
        ended December 31, 2000; and

                (b) All other reports filed pursuant to Section 13(a) or 15(d)
        of the Securities Exchange Act of 1934 (the "Exchange Act") since the
        end of the fiscal year covered by the Registrant document referred to in
        (a) above.

                (c) The Registrant's Registration Statement No. 000-31311 on
        Form 8-A12G, as amended, filed with the SEC on August 10, 2000, in which
        are described the terms, rights and provisions applicable to the
        Registrant's Common Stock.

All documents subsequently filed by the Registrant pursuant to Sections 13(a),
13(c), 14, and 15(d) of the Exchange Act, prior to the filing of a post-
effective amendment which indicates that all securities offered have been sold
or which deregisters all securities then remaining unsold, shall be deemed to be
incorporated by reference in this Registration Statement and to be a part hereof
from the date of filing of such documents.

ITEM 4. DESCRIPTION OF SECURITIES

        Not applicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL

As of the completion of this offering, Orrick, Herrington & Sutcliffe LLP and
partners in that firm beneficially own an aggregate of 14,996 shares of the
Registrant's Common Stock.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS

Section 145 of the Delaware General Corporation Law provides that a corporation
may indemnify directors and officers, as well as other employees and
individuals, against expenses (including attorneys' fees), judgments, fines and
amounts paid in settlement actually and reasonably incurred by any such person
in connection with any threatened, pending or completed actions, suits or
proceedings in which such person is made a party by reason of such person being
or having been a director, officer, employee or agent of the Registrant. The
Delaware General Corporation Law provides that Section 145 is not exclusive of
other rights to which those seeking indemnification may be entitled under any
bylaw, agreement, vote of stockholders or disinterested directors or otherwise.
Article XII of the Registrant's Amended and Restated Certificate of
Incorporation and Article VI of the Registrant's Bylaws provide for
indemnification by the Registrant of its directors and officers to the fullest
extent permitted by the Delaware General Corporation Law.



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Section 102(b)(7) of the Delaware General Corporation Law permits a corporation
to provide in its certificate of incorporation that a director of the
corporation shall not be personally liable to the corporation or its
stockholders for monetary damages for breach of fiduciary duty as a director,
except for liability (i) for any breach of the director's duty of loyalty to the
corporation or its stockholders, (ii) for acts or omissions not in good faith or
which involve intentional misconduct or a knowing violation of law, (iii) for
unlawful payments of dividends or unlawful stock repurchases, redemptions or
other distributions, or (iv) for any transaction from which the director derived
an improper personal benefit. The Registrant's Amended and Restated Certificate
of Incorporation provides for such limitation of liability.

The Registrant has obtained directors' and officers' insurance providing
indemnification for certain of the Registrant's directors, officers and
employees for certain liabilities.

The Registrant has entered into indemnification agreements with each director
and executive officer which provide indemnification under certain circumstances
for acts and omissions which may not be covered by any directors' and officers'
liability insurance.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED

        Not applicable.

ITEM 8. EXHIBITS



Exhibit
Number                                      Name
- ------                                      ----
     
4       Instruments Defining the Rights of Stockholders. Reference is made to
        Registrant's Registration Statement No. 000-31311 on Form 8-A12G,
        together with any exhibits thereto, which are incorporated herein by
        reference pursuant to Item 3(c) to this Registration Statement.

5.1     Opinion of Orrick, Herrington & Sutcliffe LLP.

23.1    Independent Auditors' Consent

23.2    Consent of Orrick, Herrington & Sutcliffe LLP is included in Exhibit 5.1
        to this Registration Statement.

24      Power of Attorney. (See page 4)

99.1    1996 Stock Option Plan and related agreements (incorporated by reference
        from Exhibit 10.8 to Registrant's Registration Statement No 333-43192 on
        Form S-1, as amended, filed with the SEC on August 7, 2000).

99.2    1997 Stock Plan and related agreements (incorporated by reference from
        Exhibit 10.9 to Registrant's Registration Statement No 333-43192 on Form
        S-1, as amended, filed with the SEC on August 7, 2000).

99.3    2001 Stock Plan and related agreements (incorporated by reference from
        Exhibit No. 10.10 to Registrant's Registration Statement No. 333-43192
        on Form S-1, as amended, filed with the SEC on August 7, 2000).

99.4    2001 Employee Stock Purchase Plan (incorporated by reference from
        Exhibit No. 10.11 to Registrant's Registration Statement No. 333-43192
        on Form S-1, as amended, filed with the SEC on August 7, 2000).




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ITEM 9. UNDERTAKINGS

        (a) The undersigned Registrant hereby undertakes:

                (1) To file, during any period in which offers or sales are
        being made, a post-effective amendment to this Registration Statement:

                        (i) To include any prospectus required by Section
        10(a)(3) of the Securities Act;

                        (ii) To reflect in the prospectus any facts or events
        arising after the effective date of the Registration Statement (or the
        most recent post- effective amendment thereof) which, individually or in
        the aggregate, represent a fundamental change in the information set
        forth in the Registration Statement. Notwithstanding the foregoing, any
        increase or decrease in volume of securities offered (if the dollar
        value of securities offered would not exceed that which was registered)
        and any deviation from the low or high end of the estimated maximum
        offering range may be reflected in the form of prospectus filed with the
        Commission pursuant to Rule 424(b) if, in the aggregate, the changes in
        volume and price represent no more than a 20% change in the 3 maximum
        aggregate offering price set forth in the "Calculation of Registration
        Fee" table in the effective Registration Statement;

                        (iii) To include any material information with respect
        to the plan of distribution not previously disclosed in the Registration
        Statement or any material change to such information in the Registration
        Statement;

        Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply
        if the information required to be included in a post-effective amendment
        by those paragraphs is contained in periodic reports filed by the
        Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act
        that are incorporated by reference in the Registration Statement.

                (2) That, for the purpose of determining any liability under the
        Securities Act, each such post-effective amendment shall be deemed to be
        a new registration statement relating to the securities offered therein,
        and the offering of such securities at that time shall be deemed to be
        the initial bona fide offering thereof.

                (3) To remove from registration by means of a post-effective
        amendment any of the securities being registered which remain unsold at
        the termination of the offering.

        (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Exchange Act) that is
incorporated by reference in the Registration Statement shall be deemed to be a
new Registration Statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

        (c) Insofar as indemnification for liabilities arising under the
Securities Act may be permitted to directors, officers and controlling persons
of the Registrant pursuant to the foregoing provisions, or otherwise, the
Registrant has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Act and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by the Registrant of expenses incurred
or paid by a director, officer or controlling person of the Registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

Registrant of expenses incurred or paid by a director, officer or controlling
person of the Registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, the Registrant will, unless in
the opinion of its counsel the matter has been settled by controlling precedent,
submit to a court of appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in the Securities
Act and will be governed by the final adjudication of such issue.



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                                   SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of San Jose, State of California, on the 3rd of August,
2001.

PDF SOLUTIONS, INC.
(Registrant)

By: /s/ JOHN K. KIBARIAN
   ------------------------------------------
   John K. Kibarian
   President and Chief Executive Officer

By: /s/ P. STEVEN MELMAN
   ------------------------------------------
   P. Steven Melman
   President and Chief Executive Officer
   Principal Financial and Accounting Officer

                                POWER OF ATTORNEY

Each of the undersigned directors of PDF Solutions, Inc., a Delaware corporation
(the "Company"), hereby constitutes and appoints John K. Kibarian and P. Steven
Melman, and each of them, his true and lawful attorneys-in-fact, with full power
of substitution, for him or her and in his or her name, place and stead, in his
or her capacity as a director, to execute a Registration Statement or
Registration Statements on Form S-8 under the Securities Act of 1933, as
amended, relating to 4,493,985 shares of Common Stock that are issuable under
the PDF Solutions, Inc. 1996 Stock Option Plan, the 1997 Stock Plan, the 2001
Stock Plan, and the 2001 Employee Stock Purchase Plan (the "Plans") and any and
all amendments (including post-effective amendments) to such Registration
Statements, and to file such Registration Statements and any and all amendments
thereto, with exhibits thereto, and other documents in connection therewith,
with the Securities and Exchange Commission, granting unto such
attorneys-in-fact full power and authority to do and perform each and every act
and thing necessary or desirable to be done in and about the premises, as fully
to all intents and purposes, as he or she might or could do in person, and
ratify and confirm all that such attorneys-in-fact or their substitutes may
lawfully do or cause to be done by virtue hereof, and hereby consents to such
registration of the Shares and the issuance thereof pursuant to the terms of the
Plan. Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.



              Signature                                Title
              ---------                                -----
                                      

                                             Chief Executive Officer,
- ------------------------------                President and Director
       John K. Kibarian

                                         Chief Financial Officer and Vice
- ------------------------------                President, Finance and
       P. Steven Melman                           Administration

                                            Vice President, Integration
- ------------------------------                 Practice and Director
        Kimon Michaels

     /s/ B. J. CASSIN                                Director
- -----------------------------
         B. J. Cassin

                                                     Director
- -----------------------------
       Donald L. Lucas

                                                     Director
- -----------------------------
       Lucio L. Lanza





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                                  EXHIBIT INDEX



Exhibit
Number                                       Name
- ------                                       ----
     
4       Instruments Defining the Rights of Stockholders. Reference is made to
        Registrant's Registration Statement No. 000-31311 on Form 8-A12G,
        together with any exhibits thereto, which are incorporated herein by
        reference pursuant to Item 3(c) to this Registration Statement.

5.1     Opinion of Orrick, Herrington & Sutcliffe LLP.

23.1    Independent Auditors' Consent

23.2    Consent of Orrick, Herrington & Sutcliffe LLP is included in Exhibit 5.1
        to this Registration Statement.

24      Power of Attorney. (See page 4)

99.1    1996 Stock Option Plan and related agreements (incorporated by reference
        from Exhibit 10.8 to Registrant's Registration Statement No 333-43192 on
        Form S-1, as amended, filed with the SEC on August 7, 2000).

99.2    1997 Stock Plan and related agreements (incorporated by reference from
        Exhibit 10.9 to Registrant's Registration Statement No 333-43192 on Form
        S-1, as amended, filed with the SEC on August 7, 2000).

99.3    2001 Stock Plan and related agreements (incorporated by reference from
        Exhibit No. 10.10 to Registrant's Registration Statement No. 333-43192
        on Form S-1, as amended, filed with the SEC on August 7, 2000).

99.4    2001 Employee Stock Purchase Plan (incorporated by reference from
        Exhibit No. 10.11 to Registrant's Registration Statement No. 333-43192
        on Form S-1, as amended, filed with the SEC on August 7, 2000).





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