EXHIBIT 5.01
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                               September 19, 2001

VeriSign, Inc.
487 East Middlefield Road
Mountain View, California  94043-1331

Gentlemen/Ladies:

         At your request, we have examined the Registration Statement on Form
S-8 (the "Registration Statement") to be filed by VeriSign, Inc., a Delaware
corporation (the "Company"), with the Securities and Exchange Commission (the
"Commission") on or about September 21, 2001 in connection with the registration
under the Securities Act of 1933, as amended, of an aggregate of 15,000,000
shares of the Company's Common Stock (the "Stock"), subject to issuance by the
Company upon the exercise of stock options granted or to be granted under the
Company's 2001 Stock Incentive Plan (the "Plan"). In rendering this opinion, we
have examined the following.

         (1)      the Company's Third Amended and Restated Certificate of
                  Incorporation, certified by the Delaware Secretary of State on
                  October 19, 2000;

         (2)      the Certificate of Amendment to the Company's Third Amended
                  and Restated Certificate of Incorporation, certified by the
                  Delaware Secretary of State on June 8, 2000;

         (3)      the Company's Bylaws, certified by the Company's Secretary on
                  October 23, 2000;

         (4)      the Registration Statement, together with the exhibits filed
                  as a part thereof or incorporated therein by reference,
                  including the Plan and related forms of enrollment form,
                  subscription agreement, notice of withdrawal and notice of
                  suspension;

         (5)      the Prospectus prepared in connection with the Registration
                  Statement (the "Prospectus");

         (6)      copies of the minutes of meetings and actions by written
                  consent of the Company's Board of Directors approving the Plan
                  that have been provided to us by the Company;

         (7)      a certificate from the Company's transfer agent of even date
                  herewith verifying the number of the Company's issued and
                  outstanding shares of capital stock as of the date hereof and
                  a list of option and warrant holders respecting the Company's
                  capital stock and of any rights to purchase capital stock that
                  was prepared by the Company and dated September 19, 2001
                  verifying the number of such issued and outstanding
                  securities; and

         (8)      a Management Certificate addressed to us and dated of even
                  date herewith executed by the Company containing certain
                  factual and other representations (the "Management
                  Certificate").

         In our examination of documents for purposes of this opinion, we have
assumed, and express no opinion as to, the genuineness of all signatures on
original documents, the authenticity and completeness of all documents submitted
to us as originals, the conformity to originals and completeness of all
documents submitted to us as copies, the legal capacity of all persons or
entities executing the same, the lack of any undisclosed termination,
modification, waiver or amendment to any document reviewed by us and the due
authorization, execution and delivery of all documents where due authorization,
execution and delivery are prerequisites to the effectiveness thereof.





         As to matters of fact relevant to this opinion, we have relied solely
upon our examination of the documents referred to above and have assumed the
current accuracy and completeness of the information obtained from the documents
referred to above and the representations and warranties made by representatives
of the Company to us, including but not limited to those set forth in the
Management Certificate. We have made no independent investigation or other
attempt to verify the accuracy of any of such information or to determine the
existence or non-existence of any other factual matters; however, we are not
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aware of any facts that would cause us to believe that the opinion expressed
herein is not accurate.

         We are admitted to practice law in the State of California, and we
render this opinion only with respect to, and express no opinion herein
concerning the application or effect of the laws of any jurisdiction other than,
the existing laws of the United States of America, of the State of California
and, with respect to the validity of corporate action and the requirements for
the issuance of stock, of the State of Delaware.

         Based upon the foregoing, it is our opinion that the 15,000,000 shares
of Stock that may be issued and sold by the Company upon the exercise of stock
options granted or to be granted under the Plan, when issued, sold and delivered
in accordance with the applicable plan and purchase agreements to be entered
into thereunder and in the manner and for the consideration stated in the
Registration Statement and the Prospectus, will be validly issued, fully paid
and nonassessable.

         We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to all references to us, if any, in the
Registration Statement, the Prospectus constituting a part thereof and any
amendments thereto. This opinion speaks only as of its date and we assume no
obligation to update this opinion should circumstances change after the date
hereof. This opinion is intended solely for use in connection with issuance and
sale of shares subject to the Registration Statement and is not to be relied
upon for any other purpose.

                                                     Very truly yours,

                                                     FENWICK & WEST LLP