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                                                                     EXHIBIT 4.5

                          REGISTRATION RIGHTS AGREEMENT


     THIS REGISTRATION RIGHTS AGREEMENT, dated as of December 21, 2001 is
between Tradenable Inc., a Delaware corporation ("Seller"), and ValiCert, Inc.,
a Delaware corporation (the "Company").

     WHEREAS, the parties entered into the Asset Purchase and Sale Agreement,
dated December 12, 2001, (the "Purchase Agreement") pursuant to which Seller
received one million (1,000,000) shares of common stock of the Company (terms
not defined herein shall have the meanings ascribed to them in the Purchase
Agreement); and


     WHEREAS, the execution and delivery of this Agreement and granting to
Seller of the registration rights set forth herein with respect to the
Registrable Securities are required by the terms of the Purchase Agreement.

     NOW, THEREFORE, the parties hereto mutually agree as follows:

     Section 1.  Definitions.
                 -----------

          (a)  Registrable Securities. As used herein the term "Registrable
               ----------------------
     Securities" means all Shares, if any, that (i) have not been sold under the
     Registration Statement, (ii) have not been sold under circumstances under
     which all of the applicable conditions of Rule 144 (or any similar
     provision then in force) under the Securities Act ("Rule 144") are met,
     (iii) have not been otherwise transferred to persons who may trade such
     Registrable Securities without restriction under the Securities Act, and
     the Company has delivered a new certificate or other evidence of ownership
     for such Registrable Securities not bearing a restrictive legend, or (iv)
     may not be sold without any time, volume or manner limitations pursuant to
     Rule 144(k) (or any similar provision then in effect) under the Securities
     Act. In the event of any merger, reorganization, consolidation,
     recapitalization or other change in corporate structure affecting the
     Common Stock, such adjustment shall be deemed to be made in the definition
     of "Registrable Security" as is appropriate in order to prevent any
     dilution or enlargement of the rights granted pursuant to this Agreement.

          (b)  Holder. As used herein the term "Holder" means any person owning
               ------
     or having the right to acquire Registrable Securities or any assignee
     thereof in accordance with Section 3 of this Agreement.

          (c)  Potential Material Event. As used herein the term "Potential
               ------------------------
     Material Event" shall have the meaning ascribed to it in Section 3(j)
     hereof.

     Section 2.  Restrictions on Transfer. Holders acknowledge and understand
                 ------------------------
that in the absence of an effective Registration Statement authorizing the
resale of the Registrable Securities, as provided herein, the Registrable
Securities are "restricted securities" as defined in Rule 144. Holders
understand that no disposition or transfer of the Registrable Securities may be
made by Holders in the absence of (i) an opinion of counsel to the Seller, in

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form and substance reasonably satisfactory to the Company that such transfer may
be made without registration under the Securities Act, or (ii) such
registration.

     With a view to making available to Holders the benefits of Rule 144, the
Company agrees to:

          (a)  comply with the provisions of paragraph (c)(1) of Rule 144; and

          (b)  to file with the Commission in a timely manner all reports and
     other documents required to be filed by the Company pursuant to Section 13
     or 15(d) under the Exchange Act; and, if at any time it is not required to
     file such reports but in the past had been required to or did file such
     reports, it will, upon the request of the Seller, make available other
     information as required by, and so long as necessary to permit sales of,
     its Registrable Securities pursuant to Rule 144.

     Section 3.  Registration Rights With Respect to the Registrable Securities.
                 --------------------------------------------------------------

          (a) The Company agrees that it will prepare and file with the
     Commission, within sixty (60) days after the date of this Agreement, a
     registration statement (on Form S-3 or other appropriate form of
     registration statement) under the Securities Act (the "Registration
     Statement"), at the sole expense of the Company (except as provided in
     Section 3(d) hereof), so as to permit a public offering and resale of the
     Registrable Securities under the Securities Act by the Holders;

          (b) The Company shall cause the Registration Statement to become
     effective five (5) days after receiving written notice of SEC clearance and
     will within said five (5) days request acceleration of effectiveness.

          (c) The Company will maintain the Registration Statement or
     post-effective amendment filed under this Section 3 hereof effective under
     the Securities Act until the earliest of (i) the date that all the
     Registrable Securities have been sold or otherwise disposed of pursuant to
     the Registration Statement, (ii) the date that all of the Registrable
     Securities have been otherwise transferred to persons who may trade such
     shares without restriction under the Securities Act, and the Company has
     delivered a new certificate or other evidence of ownership for such
     Registrable Securities not bearing a restrictive legend, or (iii) the one
     year anniversary date of this Agreement.

          (d) All fees, disbursements and out-of-pocket expenses and costs
     incurred by the Company in connection with the preparation and filing of
     the Registration Statement under subparagraph 3(a) and in complying with
     applicable securities and Blue Sky laws (including, without limitation, all
     attorneys' fees of the Company) shall be borne by the Company. The Company
     shall not be responsible for payment of any other fees, including legal
     fees, of Seller.

          (e) Holders and their counsel shall have the right, upon request, to
     review any comment letters from the SEC, and a reasonable period, not to
     exceed three (3) Trading Days, to review and comment upon the Selling
     Stockholder Table in the proposed Registration Statement, prior to its
     initial filing with the Commission.

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          (f) The Company shall make reasonably available for inspection by
     Holders, any underwriter participating in any disposition pursuant to the
     Registration Statement, and any attorney, accountant or other agent
     retained by the Holders or any such underwriter all relevant financial and
     other records, pertinent corporate documents and properties of the Company
     and its subsidiaries, and cause the Company's officers, directors and
     employees to supply all information reasonably requested by the Holders or
     any such underwriter, attorney, accountant or agent in connection with the
     Registration Statement, in each case, as is customary for similar due
     diligence examinations; provided, however, that all records, information
                             --------  -------
     and documents that are designated in writing by the Company, in good faith,
     as confidential, proprietary or containing any material non-public
     information shall be kept confidential by Holders and any such underwriter,
     attorney, accountant or agent, unless (i) such disclosure is made pursuant
     to judicial process in a court proceeding (after first giving the Company
     an opportunity promptly to seek a protective order or otherwise limit the
     scope of the information sought to be disclosed), (ii) is required by law,
     (iii) such records, information or documents become available to the public
     generally or through a third party not in violation of an accompanying
     obligation of confidentiality, (iv) that is in the possession of the using
     or disclosing party prior to the time such information was obtained from
     the Company or that is independently acquired by the using or disclosing
     party without the aid, application or use of such other information; (v)
     that is obtained by the using or disclosing party in good faith without
     knowledge of any breach of a secrecy arrangement from a third party; or
     (vi) that is disclosed in connection with any bona-fide offer to purchase
     any shares in the Company, provided that the proposed transferor obtains an
     undertaking from the proposed transferee to keep such information
     confidential in accordance with the provision of this section prior to such
     disclosure If the foregoing inspection and information gathering would
     otherwise disrupt the Company's conduct of its business, such inspection
     and information gathering shall, to the maximum extent possible, be
     coordinated on behalf of Holders and the other parties entitled thereto by
     one firm of counsel designed by and on behalf of the majority in interest
     of the Holders and other parties.

          (g) The Company shall qualify any of the Registrable Securities for
     sale in such states as a Holder reasonably designates and shall furnish
     indemnification in the manner provided in Section 6 hereof. However, the
     Company shall not be required to qualify in any state which will require an
     escrow or other restriction relating to the Company and/or the sellers, or
     which will require the Company to qualify to do business in such state or
     require the Company to file therein any general consent to service of
     process.

          (h) The Company at its expense will supply Holders with copies of the
     Registration Statement and the final prospectus included therein (the
     "Prospectus") and other related documents in such quantities as may be
     reasonably requested by Holders.

          (i) If at any time or from time to time after the effective date of
     the Registration Statement, the Company notifies Holders in writing of the
     existence of a Potential Material Event (as defined in Section 3(j) below),
     Holders shall not offer or sell any Registrable Securities pursuant to a
     Registration Statement, from the time of the

                                       3

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     giving of notice with respect to a Potential Material Event until Holder
     receives written notice from the Company that such Potential Material Event
     either has been disclosed to the public or no longer constitutes a
     Potential Material Event (the "Suspension Period"). The Company must give
     Seller notice of the existence of a Potential Material Event promptly upon
     knowledge that such an event exists and, where possible, at least two (2)
     days prior to the first day of a Suspension Period, if lawful to do so.

          (j) "Potential Material Event" means any of the following: (i) the
     possession by the Company of material information that is not ripe for
     disclosure in a registration statement, as determined in good faith by the
     Chief Executive Officer or the Board of Directors of the Company; (ii) any
     material engagement or activity by the Company which would, in the good
     faith determination of the Chief Executive Officer or the Board of
     Directors of the Company, be adversely affected by disclosure in a
     registration statement at such time, which determination shall be
     accompanied by a good faith determination by the Chief Executive Officer or
     the Board of Directors of the Company that the Registration Statement would
     be materially misleading absent the inclusion of such information, or (iii)
     pursuant to applicable law, the Company is required to file a
     post-effective amendment to the Registration Statement because the Company
     experiences a fundamental change, must change the plan of distribution to
     the Prospectus, or must update the information included in the Prospectus
     pursuant to Section 10(a)(3) of Securities Act.

     Section 4.  Cooperation with Company. The Seller will cooperate with the
                 ------------------------
Company in all respects in connection with this Agreement, including timely
supplying all information reasonably requested by the Company (which shall
include all information regarding the Seller and proposed manner of sale of the
Registrable Securities required to be disclosed in the Registration Statement)
and executing and returning all documents reasonably requested in connection
with the registration and sale of the Registrable Securities in usual and
customary form.

     Section 5.  Registration Procedures. In addition to the requirements set
                 -----------------------
forth in Section 3, the Company shall (except as otherwise provided in this
Agreement), as expeditiously as possible, subject to each Holder's assistance
and cooperation as reasonably required:

          (a) (i) prepare and file with the Commission such amendments and
     supplements to the Registration Statement and the Prospectus as may be
     necessary to keep such registration statement effective and to comply with
     the provisions of the Securities Act with respect to the sale or other
     disposition of all securities covered by such registration statement
     whenever the Seller of such Registrable Securities shall desire to sell or
     otherwise dispose of the same (including prospectus supplements with
     respect to the sales of securities from time to time in connection with a
     registration statement pursuant to Rule 415 promulgated under the
     Securities Act) and (ii) take all lawful action such that each of (A) the
     Registration Statement and any amendment thereto does not, when it becomes
     effective, contain an untrue statement of a material fact or omit to state
     a material fact required to be stated therein or necessary to make the
     statements therein not misleading and (B) the Prospectus, and any amendment
     or supplement thereto, does

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     not at any time during the Effectiveness Period include an untrue statement
     of a material fact or omit to state a material fact required to be stated
     therein or necessary to make the statements therein, in light of the
     circumstances under which they were made, not misleading;

          (b) do any and all acts and things which may be reasonably necessary
     or advisable to enable Holders to consummate the resale or other
     disposition in such jurisdiction of the Registrable Securities, except that
     the Company shall not for any such purpose be required to qualify to do
     business as a foreign corporation in any jurisdiction wherein it is not so
     qualified or to file therein any general consent to service of process;

          (c) list such Registrable Securities on the Principal Market, and any
     other exchange on which the Common Stock of the Company is then listed, if
     the listing of such Registrable Securities is then permitted under the
     rules of such exchange or the Nasdaq Stock Market;

          (d) notify Holders at any time when the Prospectus is required to be
     delivered under the Securities Act, of the happening of any event of which
     it has knowledge as a result of which the Prospectus, as then in effect,
     includes an untrue statement of a material fact or omits to state a
     material fact required to be stated therein or necessary to make the
     statements therein not misleading in the light of the circumstances then
     existing, and the Company shall prepare and file a curative amendment or
     curative supplement under Section 5(a) as quickly as possible;

          (e) as promptly as practicable after becoming aware of such event,
     notify the Seller (or, in the event of an underwritten offering, the
     managing underwriters) of the issuance by the Commission or any state
     authority of any stop order or other suspension of the effectiveness of the
     Registration Statement at the earliest possible time and take all lawful
     action to effect the withdrawal, rescission or removal of such stop order
     or other suspension;

          (f) take all such other lawful actions reasonably necessary to
     expedite and facilitate the disposition by Holders of its Registrable
     Securities in accordance with the intended methods therefor provided in the
     Prospectus; and

          (g) maintain a transfer agent for its Common Stock.

     Section 6. Indemnification.
                ---------------

          (a) The Company agrees to indemnify and hold harmless each Holder and
     each person, if any, who controls the Holder within the meaning of the
     Securities Act ("Distributing Seller") against any losses, claims, damages
     or liabilities, joint or several (which shall, for all purposes of this
     Agreement, include, but not be limited to, all reasonable costs of defense
     and investigation and all reasonable attorneys' fees), to which Holder may
     become subject, under the Securities Act or otherwise, insofar as such
     losses, claims, damages or liabilities (or actions in respect thereof)
     arise out of or are based upon any untrue statement or alleged untrue
     statement of any material fact contained in the Registration Statement, or
     any related preliminary prospectus, the Prospectus or

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     amendment or supplement thereto, or arise out of or are based upon the
     omission or alleged omission to state therein a material fact required to
     be stated therein or necessary to make the statements therein in light of
     the circumstances when made not misleading; provided, however, that the
     Company will not be liable in any such case to the extent that any such
     loss, claim, damage or liability arises out of or is based upon an untrue
     statement or alleged untrue statement or omission or alleged omission made
     in the Registration Statement, preliminary prospectus, the Prospectus or
     amendment or supplement thereto in reliance upon, and in conformity with,
     written information furnished to the Company by Holder specifically for use
     in the preparation thereof. This Section 6(a) shall not inure to the
     benefit of any Holder with respect to any person asserting such loss,
     claim, damage or liability who purchased the Registrable Securities which
     are the subject thereof if Holder failed to send or give a copy of the
     Prospectus to such person at or prior to the written confirmation to such
     person of the sale of such Registrable Securities, where Holder was
     obligated to do so under the Securities Act or the rules and regulations
     promulgated thereunder. This indemnity agreement will be in addition to any
     liability which the Company may otherwise have.

          (b) Each Holder agrees that it will indemnify and hold harmless the
     Company, and each officer, director of the Company or person, if any, who
     controls the Company within the meaning of the Securities Act, against any
     losses, claims, damages or liabilities (which shall, for all purposes of
     this Agreement, include, but not be limited to, all reasonable costs of
     defense and investigation and all reasonable attorneys' fees) to which the
     Company or any such officer, director or controlling person may become
     subject under the Securities Act or otherwise, insofar as such losses,
     claims, damages or liabilities (or actions in respect thereof) arise out of
     or are based upon any untrue statement or alleged untrue statement of any
     material fact contained in the Registration Statement, or any related
     preliminary prospectus, the Prospectus or amendment or supplement thereto,
     or arise out of or are based upon the omission or the alleged omission to
     state therein a material fact required to be stated therein or necessary to
     make the statements therein not misleading, but in each case only to the
     extent that such untrue statement or alleged untrue statement or omission
     or alleged omission was made in the Registration Statement, preliminary
     prospectus, the Prospectus or amendment or supplement thereto in reliance
     upon, and in conformity with, written information furnished to the Company
     by such Holder specifically for use in the preparation thereof. This
     indemnity agreement will be in addition to any liability which Holder may
     otherwise have. Notwithstanding anything to the contrary herein, Holder
     shall not be liable under this Section 6(b) for any amount in excess of the
     gross proceeds to such Holder as a result of the sale of Registrable
     Securities pursuant to the Registration Statement; provided however, that
     this provision shall not limit any rights or claims based on fraudulent or
     intentional misrepresentation, bad faith or willful misconduct.

          (c) Promptly after receipt by an indemnified party under this Section
     6 of notice of the commencement of any action, such indemnified party will,
     if a claim in respect thereof is to be made against the indemnifying party
     under this Section 6, notify the indemnifying party of the commencement
     thereof; but the omission so to notify the indemnifying party will not
     relieve the indemnifying party from any liability which it may have to any
     indemnified party except to the extent of actual prejudice demonstrated

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     by the indemnifying party. In case any such action is brought against any
     indemnified party, and it notifies the indemnifying party of the
     commencement thereof, the indemnifying party will be entitled to
     participate in, and, to the extent that it may wish, jointly with any other
     indemnifying party similarly notified, assume the defense thereof, subject
     to the provisions herein stated and after notice from the indemnifying
     party to such indemnified party of its election so to assume the defense
     thereof, the indemnifying party will not be liable to such indemnified
     party under this Section 6 for any legal or other expenses subsequently
     incurred by such indemnified party in connection with the defense thereof
     other than reasonable costs of investigation, unless the indemnifying party
     shall not pursue the action to its final conclusion. The indemnified party
     shall have the right to employ separate counsel in any such action and to
     participate in the defense thereof, but the fees and expenses of such
     counsel shall not be at the expense of the indemnifying party if the
     indemnifying party has assumed the defense of the action with counsel
     reasonably satisfactory to the indemnified party; provided that if the
     indemnified party is a Holder, the fees and expenses of such counsel shall
     be at the expense of the indemnifying party if (i) the employment of such
     counsel has been specifically authorized in writing by the indemnifying
     party, or (ii) the named parties to any such action (including any
     impleaded parties) include both Holder and the indemnifying party and
     Holder shall have been advised by such counsel in writing that there may be
     one or more legal defenses available to the indemnifying party different
     from or in conflict with any legal defenses which may be available to
     Holder (in which case the indemnifying party shall not have the right to
     assume the defense of such action on behalf of Holder, it being understood,
     however, that the indemnifying party shall, in connection with any one such
     action or separate but substantially similar or related actions in the same
     jurisdiction arising out of the same general allegations or circumstances,
     be liable only for the reasonable fees and expenses of one separate firm of
     attorneys for Holder, which firm shall be designated in writing by Holder
     and be approved by the indemnifying party). No settlement of any action
     against an indemnified party shall be made without the prior written
     consent of the indemnified party, which consent shall not be unreasonably
     withheld.

     All fees and expenses of the indemnified party (including reasonable costs
of defense and investigation in a manner not inconsistent with this Section and
all reasonable attorneys' fees and expenses) shall be promptly paid to the
indemnified party, as incurred, within ten (10) Trading Days of written notice
thereof to the indemnified party; provided, however, that the indemnifying party
may require such indemnified party to undertake to reimburse all such fees and
expenses to the extent it is finally judicially determined that such indemnified
party is not entitled to indemnification hereunder.

     Section 7.  Contribution. In order to provide for just and equitable
                 ------------
contribution under the Securities Act in any case in which (i) the indemnified
party makes a claim for indemnification pursuant to Section 6 hereof but is
judicially determined (by the entry of a final judgment or decree by a court of
competent jurisdiction and the expiration of time to appeal or the denial of the
last right of appeal) that such indemnification may not be enforced in such case
notwithstanding the fact that the express provisions of Section 6 hereof provide
for indemnification in such case, or (ii) contribution under the Securities Act
may be required on the part of any indemnified party, then the Company and the
applicable Holder shall contribute to

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the aggregate losses, claims, damages or liabilities to which they may be
subject (which shall, for all purposes of this Agreement, include, but not be
limited to, all reasonable costs of defense and investigation and all reasonable
attorneys' fees), in either such case (after contribution from others) on the
basis of relative fault as well as any other relevant equitable considerations.
The relative fault shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission or alleged omission to state a material fact relates to information
supplied by the Company on the one hand or the applicable Holder on the other
hand, and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such statement or omission. The Company and
Holder agree that it would not be just and equitable if contribution pursuant to
this Section 7 were determined by pro rata allocation or by any other method of
allocation which does not take account of the equitable considerations referred
to in this Section 7. The amount paid or payable by an indemnified party as a
result of the losses, claims, damages or liabilities (or actions in respect
thereof) referred to above in this Section 7 shall be deemed to include any
legal or other expenses reasonably incurred by such indemnified party in
connection with investigating or defending any such action or claim. No person
guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of
the Securities Act) shall be entitled to contribution from any person who was
not guilty of such fraudulent misrepresentation.

     Notwithstanding any other provision of this Section 7, in no event shall
any (i) Holder be required to undertake liability to any person under this
Section 7 for any amounts in excess of the dollar amount of the gross proceeds
to be received by the Holder from the sale of Holder's Registrable Securities
(after deducting any fees, discounts and commissions applicable thereto)
pursuant to any Registration Statement under which such Registrable Securities
are or were to be registered under the Securities Act and (ii) underwriter be
required to undertake liability to any person hereunder for any amounts in
excess of the aggregate discount, commission or other compensation payable to
such underwriter with respect to the Registrable Securities underwritten by it
and distributed pursuant to the Registration Statement

     Section 8.  Notices. All notices, demands, requests, consents, approvals,
                 -------
and other communications required or permitted hereunder shall be in writing
and, unless otherwise specified herein, shall be delivered as set forth in the
Purchase Agreement.

     Section 9.  Assignment. Subject to Section 2 hereof, (a) the rights of a
                 ----------
Holder may be assigned by a Holder to any other person, and (b) the provisions
of this Agreement shall inure to the benefit of, and be enforceable by, any such
transferee of any of the Registrable Securities other than through open-market
sales.

     Section 10.  Counterparts/Facsimile. This Agreement may be executed in
                  ----------------------
two (2) or more counterparts, each of which shall constitute an original, but
all of which, when together shall constitute but one and the same instrument,
and shall become effective when one (1) or more counterparts have been signed by
each party hereto and delivered to the other party. In lieu of the original, a
facsimile transmission or copy of the original shall be as effective and
enforceable as the original.

     Section 11.  Remedies and Severability. The remedies provided in this
                  -------------------------
Agreement are cumulative and not exclusive of any remedies provided by law. If
any term,

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provision, covenant or restriction of this Agreement is held by a board of
arbitration or a court of competent jurisdiction to be invalid, illegal, void or
unenforceable, the remainder of the terms, provisions, covenants and
restrictions set forth herein shall remain in full force and effect and shall in
no way be affected, impaired or invalidated, and the parties hereto shall use
their best efforts to find and employ an alternative means to achieve the same
or substantially the same result as that contemplated by such term, provision,
covenant or restriction. It is hereby stipulated and declared to be the
intention of the parties that they would have executed the remaining terms,
provisions, covenants and restrictions without including any of those that may
be hereafter declared invalid, illegal, void or unenforceable.

     Section 12.  Conflicting Agreements. The Company shall not enter into any
                  ----------------------
agreement with respect to its securities that is inconsistent with the rights
granted to the purchasers of Registrable Securities in this Agreement or
otherwise prevents the Company from complying with all of its obligations
hereunder.

     Section 13.  Headings. The headings in this Agreement are for reference
                  --------
purposes only and shall not affect in any way the meaning or interpretation of
this Agreement.

     Section 14. Governing Law. This Agreement will be governed by and construed
                 -------------
in accordance with the internal laws of the State of California applicable to
contracts made among residents of, and wholly to be performed within, the State
of California, without regard to principles of conflict of laws or choice of
laws.

                            [SIGNATURE PAGE FOLLOWS]


                                       9

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     IN WITNESS WHEREOF, the parties hereto have executed this Registration
Rights Agreement as of the date first written above.

COMPANY:

VALICERT, INC.

By:  /s/ Joseph (Yosi) Amram
   ------------------------------------
Name:  Joseph (Yosi) Amram
Title:  President and CEO

Address:      339 N. Bernardo Avenue
              Mountain View, CA 94043




SELLER:

Tradenable Inc.

By: /s/ Woodson Hobbs
   ------------------------------------
Name:  Woodson Hobbs
Title:  Chief Executive Officer

Address:      2600 Bridge Parkway, Suite 201
              Redwood Shores, CA  94065