EXHIBIT 10.13
 
                            SUBSCRIPTION AGREEMENT
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     THIS SUBSCRIPTION AGREEMENT ("AGREEMENT") by and between _______________
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(the "PURCHASER"), and Digital Certificates International, Inc., a Delaware
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corporation (the "COMPANY"), is dated as of this 18th day of April, 1995.
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                               A G R E E M E N T

     1.   SALE OF STOCK.  Purchaser agrees on the date hereof to purchase
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________________________________ (_______) shares of the Company's Common
Stock (the "STOCK") for a purchase price of Twelve Cents ($0.12) per share
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or an aggregate purchase price of ________________________ (__________). The
purchase price shall be payable by delivery of a cashier's check, certified
check, or other check acceptable to the Company made payable to the Company.

          The Company shall deliver a certificate representing the Stock to the
Purchaser as soon as is practicable after the date of this Agreement.

     2.   REPRESENTATIONS OF PURCHASER.  Because of the exemptions from the
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registration requirements of the federal Securities Act of 1933 (the "ACT")
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and from the California Corporate Securities Law of 1968 (the "LAW")
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relied upon by the Company in making the sale of the 

 
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Stock to the Purchaser, the Purchaser hereby warrants that the Purchaser:

          1.1  Is aware that the Stock is highly speculative and that there can
be no assurance as to what return, if any, there may be.

          1.2  Is aware of the Company's business affairs and financial
condition; has acquired sufficient information about the Company to reach an
informed and knowledgeable decision to acquire the Stock; has received, read and
understood the Company's Strategic Business Plan dated September 1994 and the
documents referenced therein; and has received an opportunity to ask questions
relating to the Company's business, legal and financial affairs and to obtain
all additional information which Purchaser or his or her purchaser
representative or professional adviser requested.

          1.3  Is purchasing the Stock for investment for the Purchaser's
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own account only and not as a nominee or agent, and not with a view to, or for
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resale in connection with, any "distribution" thereof within the meaning of the
Act or the Law.

          1.4  Does not have any contract, undertaking, agreement or arrangement
with any person to sell, transfer or grant a participation in the Stock to such
person or to any third person.

          1.5  Understands that the Stock has not been registered under the Act
or qualified under the Law by reason of specific 

 
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exemptions therefrom, which exemptions may depend upon, among other things, the
bona fide nature of the Purchaser's investment intent as expressed herein. In
this connection, the Purchaser understands that, in the view of the Securities
and Exchange Commission (the "COMMISSION"), the statutory basis for such
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exemption from the Act may not be available if the Purchaser's representations
mean that the Purchaser's present intention is to hold the Stock for a minimum
capital gains period under the tax statutes, for a deferred sale, for a market
rise, for a sale if the market does not rise, or for a year or any other fixed
period in the future.

          1.6  Further understands that the Stock must be held indefinitely
unless it is subsequently registered under the Act and qualified under the Law
or an exemption from such registration and such qualification is available.

          1.7  Is aware of Rule 144 promulgated under the Act which permits
limited public resale of stock acquired in a nonpublic offering, subject to the
satisfaction of certain conditions, including, among other things, the
availability of certain current public information about the Company, the
passage of not less than two years after the holder has purchased and completed
payment for the stock to be sold, effectuation of the sale on the public market
through a broker in an unsolicited "broker's transaction" or to a "market
maker", and compliance with specified limitations on the 

 
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amount of securities to be sold (generally, one percent (1%) of the total amount
of common stock outstanding) during any three-month period; provided, however,
that such conditions need not be met by a person who is not an affiliate of the
Company at the time of the sale and has not been an affiliate for the preceding
three months, if the securities have been beneficially owned by such person for
at least three years prior to their sale. The Purchaser understands that the
Company's Common Stock may not be publicly traded or the Company may not be
satisfying the current public information requirements of Rule 144 at the time
the Purchaser wishes to sell the Stock; and thus, the Purchaser may be precluded
from selling the Stock under Rule 144 even though the two-year minimum holding
period may have been satisfied. In addition, the Purchaser is aware that Rule
144 does not affect the Purchaser's obligations under the Law and,
notwithstanding the availability of Rule 144, the Stock may not be sold unless
it is qualified under the Law or an exemption from such qualification is
available.

          1.8  Further understands that in the event the requirements of Rule
144 are not met, registration under the Act, compliance with Regulation A or
some other registration exemption will be required for any disposition of the
Stock; and that, although Rule 144 is not exclusive, the Commission has
expressed its opinion that persons proposing to sell private placement
securities other than in a registered offering and other than pursuant to Rule
144 will have a 

 
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substantial burden of proof in establishing that an exemption from registration
is available for such offers or sales and that such persons and the brokers who
participate in such transactions do so at their own risk.

          1.9  Has either (i) a preexisting business or personal relationship
with the Company or its directors or officers or (ii) by reason of Purchaser's
business or financial experience, the capacity to protect Purchaser's own
interest in connection with the transaction contemplated by this Agreement.

          1.10 Is (i) experienced in investing in companies recently organized
and in the development stage, (ii) able to fend for itself in connection with
this investment and (iii) able to bear the economic risk of this investment.

     2.   OTHER AGREEMENTS.  In consideration for the Company agreeing to its
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obligations in this Agreement, and in consideration of Purchaser's purchase of
the Stock hereunder, the parties hereto agree to enter:

          (i)  that certain Stockholder's Agreement by and among the Company,
Purchaser, and certain holders of the Company's Common and Series A Preferred
Stock; and

 
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          (ii) that certain Registration Rights Agreement by and among the
Company, Purchaser, and certain other holders of the Company's Series A
Preferred Stock and Common Stock.

     3.   CALIFORNIA COMMISSIONER OF CORPORATIONS - CORPORATE SECURITIES LAW.
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     THE SALE OF THE SECURITIES WHICH ARE THE SUBJECT OF THIS AGREEMENT HAS NOT
     BEEN QUALIFIED WITH THE COMMISSIONER OF CORPORATIONS OF THE STATE OF
     CALIFORNIA AND THE ISSUANCE OF SUCH SECURITIES OR THE PAYMENT OR RECEIPT OF
     ANY PART OF THE CONSIDERATION THEREFOR PRIOR TO SUCH QUALIFICATION IS
     UNLAWFUL, UNLESS THE SALE OF SECURITIES IS EXEMPT FROM THE QUALIFICATION BY
     SECTION 25100, 25102, OR 25105 OF THE CALIFORNIA CORPORATIONS CODE.  THE
     RIGHTS OF ALL PARTIES TO THIS AGREEMENT ARE EXPRESSLY CONDITIONED UPON SUCH
     QUALIFICATION BEING OBTAINED UNLESS THE SALE IS SO EXEMPT.


     4.   LEGENDS.  All certificates representing any shares of Stock subject to
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the provisions of this Agreement shall have endorsed thereon the following
legends:

          1.1  SECURITIES LAWS.  The securities represented by this certificate
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have been acquired for the Purchaser's own account and not with a view to, or
for resale in connection with, any distribution thereof. No sale or other
disposition of such securities may be effected without the (1) registration of
such sale or disposition under the Securities Act of 1933, as amended, and (2)
qualification of such sale or disposition under the California Corporate
Securities Law of 1968, as amended, or an opinion of counsel 

 
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in form and substance satisfactory to the Company such that registration and
qualification are not required.

     2.   AGREEMENT TO LOCK-UP IN THE EVENT OF A PUBLIC OFFERING.  The
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Purchaser hereby agrees that for a period of not less than 90 days and up to a
maximum of 180 days following the effective date of the first registration
statement of the Company covering Common Stock (or other securities) to be sold
on its behalf in an underwritten public offering, he shall not, to the extent
requested by the Company and any underwriter, sell or otherwise transfer  or
dispose of (other than to donees who agree to be similarly bound) any Common
Stock of the Company held by him at any time during such period except Common
Stock included in such registration; provided, however, that all officers and
directors of the Company who hold securities of the Company or options to
acquire securities of the Company enter into similar agreements.

     3.   ACCEPTANCE BY THE COMPANY.  This Agreement shall not become effective
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until the Company's acceptance, which shall only be given after the
Company's determination that the sale of the Stock is exempt from the
registration provisions of the Act and qualified under, or exempt from
qualification provisions of, the Law.

 
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     IN WITNESS WHEREOF, the parties have executed this Agreement as of the day
first hereinabove written.

                                     PURCHASER:



                                     ___________________________________
                                     Name
 
                                     ___________________________________   
                                     Title   


                                     COMPANY:

                                     DIGITAL CERTIFICATES INTERNATIONAL, INC.



                                     By:________________________________
                                     

                                     ___________________________________   
                                     Name
 
                                     ___________________________________   
                                     Title