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                                  EXHIBIT 10.16

Agreement dated as of March 2nd , 2001 by and between NOCOPI TECHNOLOGIES, INC.,
a corporation organized and existing under the laws of Maryland, with officers
at 537 Apple Street, West Conshohocken, Pennsylvania 19428-2903 (`NOCOPI"), and
WESTVACO BRAND SECURITY, INC., a corporation organized and existing under the
laws of Delaware, with offices at One High Ridge Park, Stamford, Connecticut
06905, and its AFFILIATES ("LICENSEE").

1. This Agreement amends a certain Agreement dated December 19, 2000 (the
   "Agreement of Amendment") and further amends a certain License Agreement (the
   "License Agreement") between the parties dated as of September 1, 2000.

2. At any time prior to January 1, 2003, LICENSEE may, by written notice given
   to NOCOPI, elect to include EUROPE, as defined in the License Agreement,
   within TERRITORY also as defined in the License Agreement.

3. At such time as LICENSEE elects to include EUROPE within TERRITORY as
   provided in "2," NOCOPI and LICENSEE shall both service the customer accounts
   in EUROPE which NOCOPI had established or will establish. With respect to
   these accounts, NOCOPI and LICENSEE shall divide equally the proceeds from
   each account after each recovers its respective costs for that account. Such
   accounts, as existing on this date, shall be set forth by March 31, 2001 on
   Exhibit A. Accounts established by LICENSEE shall be maintained by LICENSEE
   with NOCOPI receiving the fees only as provided in the LICENSE AGREEMENT.

4. In order to enable LICENSEE to continue to service customers, NOCOPI shall
   place in escrow all of the intellectual property, including all of the
   formulae and techniques, needed to manufacture the inks used in producing
   products which incorporate Nocopi Technology as defined in the License
   Agreement.

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  The materials placed in escrow shall be released to Licensee if (i) Licensor

   shall be in material breach of its obligations under the License Agreement,
   (ii) Licensor (or any successor) shall cease to conduct business as a going
   concern, or (iii) Licensor, as a debtor in bankruptcy proceedings, shall
   reject the License Agreement pursuant to Section 365 of the Bankruptcy Code
   (11 U.S.C. Section 365).

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

NOCOPI TECHNOLOGIES, INC.                   WESTVACO BRAND SECURITY, INC.

By /s/                                      By /s/
   ---------------------------------           ---------------------------------
   Michael A. Feinstein, M. D.                 Stanley G. Hart
   Chairman                                    President<PAGE>

                                  EXHIBIT 10.17

                            STOCK PURCHASE AGREEMENT

The shares of common stock offered and sold hereby have not been registered
under the Securities Act of 1933, as amended (the "Securities Act"), or the
securities laws of any state or other jurisdiction. These shares have been
offered and will be sold in reliance upon exemptions from the registration
requirements of the securities act and such laws. The sale or other disposition
of these shares is restricted in accordance with the Securities Act and such
laws, and may only be made pursuant to a registration under the Securities Act
and those laws unless an exemption from the registration requirements thereof is
available. No offer, sale or other disposition of these shares may be made,
directly or indirectly, except in accordance with the Securities Act and such
laws, and the rules thereunder.

         STOCK PURCHASE AGREEMENT dated the 20th day of February, 2001 between
NOCOPI TECHNOLOGIES, INC., a Maryland corporation (the "Company"), and WESTVACO
BRAND SECURITIES, INC., a Delaware corporation (the "Investor").

                              W I T N E S S E T H:

         WHEREAS, the Company proposed to offer and sell to Investor and
Investor proposes to purchase from the Company an aggregate of 3,917,030 shares
of the authorized and unissued common stock, par value $.0.01 per share (the
"Shares") of the Company, all on the terms and conditions set forth in this
Agreement;

         NOW, THEREFORE, the Company and Investor hereby agree as follows:

         1. Purchase and Delivery. Investor hereby subscribes for and agrees to
purchase, and the Company hereby agrees to sell to Investor, an aggregate of
3,917,030 Shares for an aggregate purchase price equal to $325,000. Investor
shall promptly pay $300,000 on account of the purchase price to the Company in
cash, by check or by wire transfer made in accordance with the Company's written
instructions; the $25,000 balance of the purchase price shall be paid by
crediting the Company's account payable to Investor and the Company shall
promptly issue the Shares purchased to Investor. The Shares shall be represented
by one or more share certificates, as Investor may reasonably direct.

         2. Investor's Representations and Warranties. Investor represents and
warrants to the Company, and acknowledges and intends that the Company rely
thereon, as follows:

                  (a) Investor is acquiring the Shares for Investor's own
account, for investment purposes only and not with a view to making any
distribution of such Shares, and no other person has a direct or indirect
beneficial interest in such Shares;
                                       -1-

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                  (b) Investor is aware that the Shares are not registered under
the Securities Act or any state securities laws, and are restricted securities.
The sale or other disposition of the Shares by Investor is restricted in
accordance with the Securities Act and such laws, and may only be made pursuant
to a registration under the Securities Act and those laws unless an exemption
from the registration requirements thereof is available;

                  (c) Investor has investigated the purchase of the Shares to
the extent Investor deems necessary or desirable. Investor has such knowledge
and experience in financial and business matters that Investor is capable of
evaluating the merits and risks of the acquisition of the Shares and of making
an informed investment decision with respect thereto and Investor has the
ability to bear the economic risk of an investment in the Company and to
withstand a complete loss of his investment. Investor is financially able to
hold the Shares for an indefinite period of time;

                  (d) Investor has been furnished by the Company with copies of
the Company's Annual Report on Form 10-KSB for the Company's fiscal year ended
December 31, 1999, the Company's Quarterly Reports on Form 10-QSB for the
Company's fiscal quarters ended March 31, 2000, June 30, 2000 and September 30,
2000 as filed with the Securities and Exchange Commission (the "SEC") and all
other reports filed by the Company with the SEC on or after March 31, 2000
(collectively, the "Company's SEC Reports"). Investor has been afforded an
opportunity to ask questions of, and receive answers from, representatives of
the Company concerning the terms and conditions of Investor's purchase of the
Shares and all other relevant matters and has been afforded the opportunity to
obtain any additional information (to the extent the Company had such
information or could acquire it without unreasonable effort or expense);

                  (e) Investor understands that no United States federal or
state agency or any agency of any other government has passed upon or made any
recommendation or endorsement of any investment in the Company;

                  (f) Investor has not been organized for the purpose of
purchasing the Shares.

                  (g) This Agreement and the transactions contemplated hereby
have been duly authorized by all necessary corporate action of Investor and its
execution and delivery by Investors does not and will not violate or conflict
with Investor's Certificate of Incorporation or by-laws, any judgment or decree
binding upon Investor or any material agreement to which Investor is a party or
by which it is bound; (ii) the undersigned natural person executing this
Agreement on behalf of Investor has the requisite right, power, capacity and
authority to enter into this Agreement on Investor's behalf; and (iii) this
Agreement will be binding on and enforceable against Investor in accordance with
its terms.

         3. Representations and Warranties of the Company. The Company
represents and warrants to Investor, and acknowledges and intends that Investor
may rely thereon, as follows:

                                       -2-

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                  (a) The Company's SEC Reports constitute all reports required
to be filed with the SEC by the Company on or after March 30, 2000. When filed,
each of the Company's SEC Reports (except to the extent revised or superseded by
a subsequent filing) complied as to form in all material respects with the
requirements of the Securities Exchange Act of 1934, as amended and the rules
and regulations promulgated thereunder and, to the Company's knowledge after
reasonable inquiry, did not contain any untrue statement of a material fact or
omit to state a material fact required to be stated therein or necessary to make
the statements made therein, in light of when they were made and the
circumstances under which they were made, not misleading.

                  (b) This Agreement and the transactions contemplated hereby
have been duly authorized by all necessary corporate action of the Company and
its execution and delivery by the Company do not and will not violate or
conflict with the Company's Articles of Incorporation or by-laws, any judgment
or decree binding upon the Company or any material agreement to which the
Company is a party or by which it is bound; (ii) the undersigned natural person
executing this Agreement on behalf of the Company has the requisite right,
power, capacity and authority to enter into this Agreement on the Company's
behalf; and (iii) this Agreement will be binding on and enforceable against the
Company in accordance with its terms;

                  (c) The Company is a corporation duly organized and validly
existing under the laws of the State of Maryland. The Company has all necessary
corporate power and authority to operate its business and presently conducted
and to enter into and perform its obligations under this Agreement. The
Company's authorized capital consists of ___ shares of common stock, par value
$__ per shares, of which ____ shares are issued and outstanding on the date
hereof. Except as described in the Company's SEC Reports, there are outstanding
no options, warrants or similar instruments entitling or authorizing any person
to purchase shares of common stock of the Company. The Shares, when paid for and
issued in accordance with this Agreement, will be duly and validly issued, fully
paid and non-assessable.

                  (d) Except for the proceedings commenced against the Company
by Euro-Nocopi, S.A in which certain shareholders of Euro-Nocopi have
intervened as plaintiffs (which have been disclosed to Investor), there is no
pending nor, to the Company's knowledge, threatened litigation or governmental
investigation or proceeding against the Company.

         4. Limitations on Transfer to be Noted on Share Certificates. Investor
under stands and acknowledges that the certificates evidencing the Shares will
be marked with a restrictive legend reflecting the unregistered status of the
Shares under the Securities Act and any applicable state securities laws. In
addition, Investor acknowledges that a notation referring to such status and the
resulting limitations on the transferability of the Shares will be placed in the
transfer records of the Company to aid in the prevention of transfers of record
without compliance with the foregoing restrictions.

                                       -3-

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         5. Other Agreements. This Agreement shall become effective when it has
been executed and delivered by the parties, provided that the parties shall also
have executed and delivered a certain Registration Rights Agreement and a
certain Collateral Assignment of Patent Rights, each of even date herewith.

         6. Miscellaneous.

                  (a) This Agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Pennsylvania without regard to
its conflicts of law rules or principles.

                  (b) This Agreement constitutes the entire agreement between
the parties hereto with respect to Investor's purchase of the Shares, and no
amendment, alteration or modification of this Agreement shall be valid, unless
such amendment, alteration or modification is expressed in a written instrument
duly executed by Investor and the Company.

                  (c) The representations and warranties made in Sections 2 and
3 of this Agreement shall survive for a period of one year following the
consummation of the transactions contemplated hereby.

                  (d) This Agreement shall inure to the benefit of and be
binding upon the successors and assigns of Investor and the Company.

                  (e) This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

                  (e) If any of the provisions contained herein shall be deemed
to be unenforceable for any reason, the parties hereto agree that this Agreement
shall be interpreted so as to be enforceable to the greatest extent possible.

                                       -4-

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         IN WITNESS WHEREOF, the parties have executed this agreement as of the
day and year first above written.

NOCOPI TECHNOLOGIES, INC.                   WESTVACO BRAND SECURITIES, INC.

By:_____________________________            By:______________________________
      Michael A. Feinstein, MD, Chairman          Stan Hart, President

                                       -5-

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