Document:

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                                                                   Exhibit 10.43

                            STOCK PURCHASE AGREEMENT

         This Stock Purchase Agreement (the "Agreement") is made as of August
20, 1999, by and among U.S. Plastic Lumber Corporation, a Nevada corporation
(the "Corporation"), and the purchasers listed on SCHEDULES A AND B hereto (each
a "Purchaser" and collectively, the "Purchasers").

         The Corporation and the Purchasers hereby agree as follows:

                                   SECTION 1.

                  AUTHORIZATION, PURCHASE AND SALE OF THE STOCK

         1.1 AUTHORIZATION OF THE STOCK. The Corporation has authorized the
issuance and sale to the Purchasers of up to Two Million One Hundred Thousand
(2,100,000) shares of the Corporation's common stock (the "Stock").

         1.2 SALE AND PURCHASE OF THE STOCK. At the Closing (as defined herein),
subject to the terms and conditions hereof and in reliance upon the
representations, warranties and agreements contained herein, each Purchaser
agrees, severally, to purchase at the Closing and the Corporation agrees to sell
and issue to each Purchaser at the Closing, that number of shares of the Stock
set forth opposite such Purchaser's name on SCHEDULES A AND B hereto for the
purchase price set forth thereon. All Purchasers shall purchase their shares
simultaneously for the same price per share.

                                   SECTION 2.

                          CLOSING, PAYMENT AND DELIVERY

         2.1 CLOSING DATE AND PLACE OF CLOSING. The purchase and sale of the
stock shall take place at the offices of the Corporation, 2300 Glades Road,
Suite 440 West, Boca Raton, FL 33431, at 10:00 a.m., on August 25, 1999, or at
such other time and place as the Corporation and the Purchasers mutually agree
upon orally or in writing (which time and place are designated as the
"Closing"). The parties intend that the Closing will occur on the third business
day subsequent to the signing of this Agreement; provided however, that if this
Agreement does not Close on or before August 28, 1999 either the Purchasers
listed on Schedule A or the Corporation may cancel this Agreement by providing
written notice of cancellation to the other.

         2.2 PAYMENT AND DELIVERY. At the Closing, the Corporation will deliver
to Purchasers' counsel a certificate representing that portion of the Stock that
each such Purchaser is purchasing against payment of the purchase price therefor
by check or wire transfer of same-day funds to the Corporation's bank account
listed on EXHIBIT A attached hereto.

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         2.3 COVENANT OF BEST EFFORTS AND GOOD FAITH. The Corporation and each
Purchaser agree to use their respective best efforts and to act in good faith to
cause to occur all conditions to Closing which are in their respective control.

                                   SECTION 3.

                REPRESENTATIONS AND WARRANTIES OF THE CORPORATION

         The Corporation hereby represents and warrants to each Purchaser that:

         3.1 INCORPORATION. The Corporation is a corporation duly organized,
validly existing and in good standing under the laws of the State of Nevada and
is qualified to do business in each jurisdiction in which the character of its
properties or the nature of its business requires such qualification, except
where the failure to so qualify would not have a material adverse effect upon
the Corporation's financial condition, business, assets or results of operations
(hereafter, a "Material Adverse Effect"). The Corporation has all requisite
corporate power and authority to carry on its business as now conducted.

         3.2 CAPITALIZATION. The authorized capital stock of the Corporation
consists of (i) 50,000,000 shares of common stock, par value $.0001 per share,
and (ii) 5,000,000 shares of preferred stock, shares of each of which class of
the capital stock of the Corporation have been issued and are outstanding as set
forth in Schedule 3.2 hereto. The terms, preferences and privileges of the
outstanding shares of capital stock are set forth in the Corporation's
Certificate of Incorporation, as amended (the "Certificate"). Except as set
forth in Schedule 3.2 hereto, there are no existing options, warrants, calls,
preemptive (or similar) rights, subscriptions or other rights, agreements,
arrangements or commitments of any character obligating the Corporation to
issue, transfer or sell, or cause to be issued, transferred or sold, any shares
of the capital stock of the Corporation or other equity interests in the
Corporation or any securities convertible into or exchangeable for such shares
of capital stock or other equity interests (collectively, "Securities"), and
there are no outstanding contractual obligations of the Corporation to
repurchase, redeem or otherwise acquire any shares of its capital stock or other
equity interests. Schedule 3.2 sets forth the number of stock options
outstanding under the Corporation's stock incentive plans, and the number of
shares reserved for issuance under such plans that are not subject to
outstanding options. Except as set forth in Schedule 3.2 no holder of any
capital stock or Securities of the Corporation has any outstanding registration
rights. For purposes of this transaction, the preemptive rights issued to
Environmental Opportunities Fund II, L.P. and Environmental Opportunities Fund
II,(Institutional) L.P. have been waived.

         3.3 AUTHORIZATION. All corporate action on the part of the Corporation,
its officers, directors and stockholders necessary for the authorization,
execution, delivery and performance of this Agreement and the consummation of
the transactions contemplated herein has been taken. When executed and delivered
by the Corporation, this Agreement shall constitute the legal, valid and binding
obligation of the Corporation, enforceable against the Corporation in accordance
with its terms, except (i) as limited by bankruptcy, insolvency, reorganization,
moratorium and other laws of general application affecting enforcement of
creditors' rights generally; (ii) as limited by laws relating to the
availability of specific performance, injunctive relief or other equitable
remedies; and (iii) to the

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extent the indemnification provisions contained in this Agreement may be limited
by applicable federal or state securities laws. The Corporation has all
requisite corporate power to enter into this Agreement and to carry out and
perform its obligations under the terms of this Agreement.

         3.4 VALID ISSUANCE OF THE STOCK. The Stock being purchased by the
Purchasers hereunder will, upon issuance pursuant to the terms hereof, be duly
authorized and validly issued, fully paid, nonassessable and free of any liens
or encumbrances created by the Corporation and will, assuming the accuracy of
the representations and warranties made by each of the Purchasers to the
Corporation, be in compliance with applicable state and federal securities laws.

         3.5 SEC DOCUMENTS. The Corporation has furnished to each Purchaser a
true and complete copy of the Corporation's Annual Report on Form 10-KSB for the
year ended December 31, 1998 and the Company's Quarterly Report on Form 10-QSB
for the six month period ended on June 30, 1999, and any other statement,
report, registration statement (other than registration statements on Form S-8)
or definitive proxy statement filed by the Corporation with the Securities and
Exchange Commission (the "SEC") during the period commencing June 30, 1999 and
ending on the date hereof. The Corporation will, promptly upon the filing
thereof, also furnish to each Purchaser all statements, reports, (including,
without limitation, Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q
and Current Reports on Form 8-K), registration statements and definitive proxy
statements filed by the Corporation with the SEC during the period commencing on
the date hereof and ending on the Closing Date (all such materials required to
be furnished to each Purchaser pursuant to this sentence or pursuant to the next
preceding sentence of this Section 3.5 being called, collectively, the "SEC
Documents"). As of their respective filing dates, the SEC Documents complied or
will comply in all material respects with the requirements of the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), or the Securities Act of
1933, as amended (the "Securities Act"), as applicable, and none of the SEC
Documents contained any untrue statement of a material fact or omitted to state
a material fact required to be stated therein or necessary in order to make the
statements made therein, in light of the circumstances under which they were
made, not misleading, as of their respective filing dates, except to the extent
corrected by a subsequently filed SEC Document. The Corporation has not filed
any amendment to its Annual Report on Form 10-KSB for the year ended December
31, 1998 or its Company's Quarterly Report on Form 10-QSB for the six month
period ended on June 30, 1999. The Corporation has not filed any Current Reports
on Form 8-K with respect to any event occurring between June 30, 1999 and the
date hereof.

         3.6 FINANCIAL STATEMENTS. The Corporation's audited Consolidated
Statements of Operations, Stockholders' Equity and Cash Flows for the fiscal
year ended December 31, 1998 and the Corporation's audited Consolidated Balance
Sheet as of December 31, 1998 are included in the Corporation's Annual Report on
Form 10-KSB for the year ended December 31, 1998, a copy of which has been
delivered to the Purchasers. The Company's unaudited Consolidated Statements of
Operations, Stockholders' Equity and Cash Flows for the six month period ended
June 30, 1999 and the Company's unaudited Consolidated Balance Sheet as of June
30, 1999 are included in the Company's Quarterly Report on Form 10-QSB for the
six month period ended on June 30, 1999, copies of which have been delivered to
the Purchasers. All of the financial statements referred to above in this
Section 3.6 are hereinafter referred to

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collectively, as the "Financial Statements". The Financial Statements have been
prepared in accordance with generally accepted accounting principles applied on
a consistent basis during the periods involved, and fairly present, in all
material respects, the financial position of the Corporation and the results of
its operations as of the date and for the periods indicated thereon, except that
those Financial Statements that are unaudited may not have been prepared in
accordance with generally accepted accounting principles solely because of the
absence of footnotes normally contained therein and may be subject to normal
year-end audit adjustments which, individually, and in the aggregate, will not
be material.

         3.7 CONSENTS. All consents, approval, orders, authorizations,
registrations, qualifications, and filings required on the part of the
Corporation to be obtained or made prior to the Closing in connection with the
execution, delivery or performance of this Agreement, and the consummation of
the transactions contemplated herein have been obtained or made or will be
obtained or made, prior to the Closing.

         3.8 NO CONFLICT. The execution and delivery of this Agreement by the
Corporation and the consummation of the transactions contemplated hereby will
not conflict with or result in any violation of or default (with or without
notice or lapse of time, or both) under, or give rise to a right of termination,
cancellation or acceleration of any obligation or to a loss of a material
benefit or give rise to an event which results in the creation of any lien,
charge or encumbrance upon any of the Corporation's properties or assets under
(i) any provision of the Certificate or Bylaws of the Corporation or (ii) any
agreement or instrument, permit, franchise, license, judgment, order, statute,
law, ordinance, rule or regulations, applicable to the Corporation or its
respective properties or assets.

         3.9 ABSENCE OF LITIGATION. There is no action, suit or proceeding or,
to the Corporation's knowledge, any investigation, pending, or to the
Corporation's knowledge, threatened against the Corporation and in which an
unfavorable outcome, ruling or finding in any said matter, or for all matters
taken as a whole, might have a Material Adverse Effect. There is not pending or
threatened any such action, suit, proceeding or investigation that questions
this Agreement or the right of the Corporation to execute, deliver and perform
under same.

         3.10 NASDAQ NATIONAL MARKET. The Common Stock is currently traded on
the Nasdaq National Market.

         3.11 BROKERS OR FINDERS. Except for Pacific Growth Equities, Inc., the
Corporation has not dealt with any broker or finder in connection with the
transactions contemplated by this Agreement, and the Corporation has not
incurred, and shall not incur, directly or indirectly, any liability for any
brokerage or finders' fees or agents commissions or any similar charges in
connection with this Agreement or any transaction contemplated hereby. All fees
payable to Pacific Growth Equities, Inc. will be paid by the Corporation.

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         3.12 COMPLIANCE WITH CHARTER, LAWS, ETC. The Corporation is in
compliance in all material respects with the terms of its Certificate and
By-laws as currently in effect, true and complete copies of which have been
delivered to each Purchaser, and each of the Certificate and By-laws of the
Corporation (in the form, provided to the Purchasers), is in full force and
effect as of the Closing Date. To the best of the Corporation's knowledge and
after due investigation, the Corporation has complied, and is in compliance
with, all federal, state, county, local and foreign laws, rules, regulations,
ordinances, decrees and orders applicable to the operation of its business or to
the real property or personal property that it owns or leases (including,
without limitation, all such laws, rules, ordinances, decrees and orders
relating to antitrust, currency exchange, environmental protection, occupational
safety and health, equal opportunity, pension, securities and
trading-with-the-enemy matters), except where any such failures to comply,
individually or in the aggregate, could not reasonably be expected to have a
Material Adverse Effect.

         3.13 PRIVATE OFFERING. During the six months preceding the date of this
Agreement, neither the Corporation nor any person acting on its behalf has,
directly or through any agent, sold, offered for sale, solicited offers to buy
or otherwise negotiated in respect of any security (as defined in the Securities
Act) that is or may be integrated with the sale of the Stock in a manner that
would require the registration of the issuance and sale by the Corporation of
the Stock under the Securities Act. During the six months preceding the date of
this Agreement, neither the Corporation nor any person acting on its behalf has
offered or sold any Stock by means of any general solicitation or general
advertising within the meaning of Rule 502(c) under the Securities Act. Assuming
the accuracy of the Purchasers' representations in Section 4 hereof, the
offering and sale of the Stock will satisfy the requirements of Rule 506 under
the Securities Act.

         3.14 CHANGES.

             (a) Since June 30, 1999, except as disclosed or in SEC Documents or
press releases prepared through or as of a date subsequent to June 30, 1999, of
which the Company has delivered all press releases since June 30, 1999 to
Zesiger Capital Group LLC, there has not been:

                  (i) any damage, destruction or loss (whether or not covered by
         insurance) to its assets which has had or is reasonably expected to
         have a Material Adverse Effect;

                  (ii) any material change in the accounting methods or
         practices followed by the Corporation;

                  (iii) any material debt, obligation or liability (whether
         absolute or contingent) incurred by the Corporation (whether or not
         presently outstanding) except (x) current liabilities incurred, and
         obligations under agreements entered into, in the ordinary course of
         business and (y) obligations or liabilities entered into or incurred in
         connection with the execution of this Agreement;

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                  (iv) any sale, lease, abandonment or other disposition by the
         Corporation of any real property or, other than in the ordinary course
         of business, of any equipment or other operating properties or, other
         than in the ordinary course of business, any sale, assignment,
         transfer, license or other disposition by the Corporation of any
         intellectual property or other intangible asset;

                  (v) any dividends or other distributions of cash or other
         property paid by the Corporation in respect of any of its capital stock
         (except for the issuance of shares of the Corporation's Common Stock
         upon exercise of rights under, or conversion of, the Corporation's
         other Securities);

                  (vi) any waivers or releases by the Corporation of any
         material debt or obligation owed to the Corporation; or

                  (vii) to the best of the Corporation's knowledge, any other
         event that could reasonably be expected to result in a Material Adverse
         Effect.

             (b) Notwithstanding anything to the contrary in this Agreement, if,
after the date of this Agreement the Corporation discloses to the Purchasers or
the Purchasers otherwise become aware of any information concerning an event
that renders the representation and warranty set forth in this Section 3.14
inaccurate, and such information is material and not otherwise available to the
public generally, the Purchasers agree not to sell, assign or otherwise transfer
any of the Stock based on such material non-public information until such
material non-public information is made available to the public generally. In
the event that the Closing contemplated hereby actually occurs, the Corporation
shall disclose such material nonpublic information in the registration statement
required to Section 7 of this Agreement.

         3.15 LABOR MATTERS. Except as set forth in Schedule 3.15, the
Corporation has no collective bargaining agreement with any of its employees
and, to the Corporation's knowledge, there is no labor union organizing activity
pending or threatened with respect to the Corporation. There are no disputes
pending or, to the knowledge of the Corporation, threatened between the
Corporation, on the one hand, and any of its employees, on the other hand, other
than employee grievances arising in the ordinary course of business which would
not, individually or in the aggregate, have a Material Adverse Effect.

                                   SECTION 4.

                REPRESENTATIONS AND WARRANTIES OF THE PURCHASERS

         Each Purchaser hereby represents, warrants and covenants to the
Corporation that:

         4.1 AUTHORIZATION. Such Purchaser has full right, power and authority
to enter into this Agreement, and such agreement constitutes its valid and
legally binding obligation, enforceable in

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accordance with its terms, except (i) as limited by applicable bankruptcy,
insolvency, reorganization, moratorium and other laws of general application
affecting enforcement of creditors' rights generally, (ii) as limited by laws
relating to the availability of specific performance, injunctive relief or other
equitable remedies, and (iii) to the extent the indemnification provisions
contained in this Agreement may be limited by applicable federal or state
securities laws.

         4.2 PURCHASE ENTIRELY FOR OWN ACCOUNT. This Agreement is made with such
Purchaser in reliance upon such Purchaser's representation to the Corporation,
which by such Purchaser's execution of this Agreement such Purchaser hereby
confirms, that the Stock to be received by such Purchaser will be acquired for
investment for such Purchaser's own account, not as a nominee or agent, and not
with a view to the resale or distribution of any part thereof, and that such
Purchaser has no present intention of selling, granting any participation in or
otherwise distributing the same. By executing this Agreement, such Purchaser
further represents that such Purchaser does not have any contract, undertaking,
agreement or arrangement with any person to sell, transfer or grant
participations to such person or to any third person, with respect to any of the
Stock.

         4.3 DISCLOSURE OF INFORMATION. Such Purchaser, individually or through
its investment advisor, Zesiger Capital Group LLC, believes it has received all
the information it considers necessary or appropriate for deciding whether to
purchase the Stock. Such Purchaser further represents that, individually or
through its investment advisor, Zesiger Capital Group LLC, it has had an
opportunity to ask questions and receive answers from the Corporation regarding
the terms and conditions of the offering of the Stock and the business,
properties, prospects and financial condition of the Corporation.

         4.4 INVESTMENT EXPERIENCE. Such Purchaser acknowledges that it can bear
the economic risk of its investment, and has, individually or through its
investment advisor, Zesiger Capital Group LLC, such knowledge and experience in
financial or business matters that it is capable of evaluating the merits and
risks of the investment in the Stock. If other than an individual, such
Purchaser also represents it has not been organized for the purpose of acquiring
the Stock.

         4.5 ACCREDITED INVESTOR. Such Investor is an "accredited investor"
within the meaning of SEC Rule 501 of Regulation D as presently in effect.

         4.6 RESTRICTED SECURITIES. Such Purchaser understands that the Stock it
is purchasing are characterized as "restricted securities" under the federal
securities laws inasmuch as they are being acquired from the Corporation in a
transaction not involving a public offering and that under such laws and
applicable regulations such Securities may be resold without registration under
the Act only in certain limited circumstances. In the absence of an effective
registration statement covering the Securities or an available exemption from
registration under the Act, the Stock must be held indefinitely. In this
connection, such Purchaser represents that it is familiar with SEC Rule 144, as
presently in effect, and understands the resale limitations imposed thereby and
by the Act, including without limitation the Rule 144 condition that current
information about the Corporation be available to the public.

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         4.7 FURTHER LIMITATIONS ON DISPOSITION. Without in any way limiting the
representations set forth above, such Purchaser further agrees not to make any
disposition of all or any portion of the Stock unless:

             (a) there is then in effect a registration statement under the
Securities Act covering such proposed disposition and such disposition is made
in accordance with such registration statement; or

             (b) it is made in compliance with Rule 144; or

             (c) such Purchaser shall have (i) notified the Corporation of the
proposed disposition and shall have furnished the Corporation with a detailed
statement of the circumstances surrounding the proposed disposition, (ii)
provided a written agreement from the transferee for the benefit of the
Corporation to be bound by the Section 4, and (iii) if requested by the
Corporation, such Purchaser shall have furnished the Corporation with an opinion
of counsel, reasonably satisfactory to the Corporation that such disposition
will not require registration of such shares under the Act. It is agreed that
the Corporation will not require opinions of counsel for transactions made
pursuant to Rule 144 except in unusual circumstances.

             (d) Notwithstanding any of the foregoing, transfers to principals
of or investment advisory clients of Zesiger Capital Group LLC shall be
permitted without any consent, statement or legal opinion.

         4.8 LEGENDS. It is understood that the certificates evidencing the
Stock it is purchasing may bear the following legend:

         "THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
         1933 OR ANY STATE SECURITIES LAWS. THEY MAY NOT BE SOLD OR OFFERED FOR
         SALE IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT AS TO THE
         SECURITIES UNDER SAID ACT AND ANY APPLICABLE STATE SECURITIES LAW OR AN
         OPINION OF COUNSEL SATISFACTORY TO THE CORPORATION THAT SUCH
         REGISTRATION IS NOT REQUIRED."

         4.9 PURCHASER COUNSEL. Such Purchaser acknowledges that such Purchaser
and, if applicable, its advisors, Zesiger Capital Group LLC, has had the
opportunity to review this Agreement, the exhibits and schedules attached hereto
and the transactions contemplated by this Agreement with such Purchaser's own
legal counsel. Each such Purchaser is relying solely on such Purchaser's legal
counsel and not on the Corporation's legal counsel, for legal advice with
respect to this investment or the transactions contemplated by this Agreement.

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         4.10 AUTHORITY OF ZESIGER CAPITAL GROUP LLC. Such Purchaser as listed
on Schedule A acknowledges that Zesiger Capital Group LLC has full right power
and authority to cause Purchaser to enter into this Agreement, bind Purchaser,
and consummate the transactions contemplated by this Agreement.

                                   SECTION 5.

                   CONDITIONS TO OBLIGATIONS OF THE PURCHASERS

         The obligation of the Purchasers to purchase the Stock is subject to
the fulfillment on or prior to the Closing Date of each of the following
conditions:

         5.1 REPRESENTATIONS AND WARRANTIES. The representations and warranties
of the Corporation shall be true and correct in all material respects on the
Closing Date as if made on such Date and the Corporation shall have an officer
provide a certificate as of the Closing Date attesting to such fact.

         5.2 PERFORMANCE. All covenants, agreements and conditions contained in
this Agreement to be performed or complied with by the Corporation on or prior
to the Closing Date shall have been performed or complied with in all material
respects.

         5.3 OPINION OF CORPORATION'S COUNSEL. The Purchasers shall have
received from counsel to the Corporation an opinion in the form attached hereto.

         5.4 LEGAL ISSUANCE. At the time of the Closing, the issuance and
purchase of the Stock shall be legally permitted by all laws and regulations to
which the Purchasers and the Corporation are subject.

         5.5 PROCEEDINGS AND DOCUMENTS. All corporate and other proceedings in
connection with the transactions contemplated hereby and all documents and
instruments incident to such transactions shall be satisfactory in form and
substance to the Purchasers and their counsel.

                                   SECTION 6.

                  CONDITIONS TO OBLIGATIONS OF THE CORPORATION

         The Corporation's obligation to sell the Stock is subject to the
fulfillment on or prior to the Closing Date of each of the following conditions:

         6.1 REPRESENTATIONS AND WARRANTIES. The representations and warranties
made by the Purchasers shall be true and correct in all material respects on the
Closing Date.

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         6.2 LEGAL ISSUANCE. At the time of the Closing, the issuance and
purchase of the Stock shall be legally permitted by all laws and regulations to
which the Purchasers and the Corporation are subject.

         6.3 PAYMENT. The Corporation shall concurrently receive payment for the
Stock as provided in Section 2.

                                   SECTION 7.

                              COVENANT TO REGISTER

         7.1 For purposes of this Section 7, the following definitions shall
apply:

             (1) The terms "register", "registered", and "registration" refer to
a registration under the Securities Act effected by preparing and filing a
registration statement or similar documents in compliance with the Securities
Act or an amendment thereto, and the declaration or ordering of effectiveness of
such registration statement, document or amendment thereto.

             (2) The term "Registrable Securities" means the Stock issued to the
Purchasers pursuant to the Agreement and any securities of the Corporation or
securities of any successor corporation issued as, or issuable upon the
conversion or exercise of any warrant, right or other security that is issued
as, a dividend or other distribution with respect to, or in exchange for or in
replacement of, such Stock.

         7.2 The Corporation agrees to file within ten (10) business days of the
Closing Date, a registration statement on Form S-3 (or other appropriate form)
in order to register the resale of the Registrable Securities and use its
reasonable best efforts to cause such registration statement to be declared
effective within 180 days after the filing of the Registration Statement (the
end of such period, the "Effectiveness Date"). If the Registration Statement is
not declared effective prior to or on the Effectiveness Date, the Company shall
pay to each Investor, in cash or additional shares (at the Company's option), an
amount equal to 1% of the product of (i) the number of Purchased Shares held by
such Investor, multiplied by (ii) the Purchase Price hereunder, being $8.25 per
share, for each 30 day period subsequent to the Effectiveness Date during which
the Registration Statement is not effective. Any additional shares so issued
will be valued on the Purchase Price and such payment will be made as soon as
practicable after each such 30 day period.

         7.3 If the Corporation proposes to register (including for this purpose
a registration effected by the Corporation for shareholders other than the
Purchaser) any of its stock or other securities under the Securities Act in
connection with a public offering of such securities (other than a registration
on Form S-4, Form S-8 or other limited purpose form or a registration effected
pursuant to agreements to register in effect on the date hereof) and the
Registrable Securities have not heretofore been included in a registration
statement under Section 7.2, which remains effective, the Corporation shall, at
such time, promptly give the Purchasers written notice of such registration.

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Upon the written request of any Purchaser given within 10 days after receipt of
such notice by such Purchaser, the Corporation shall cause to be registered
under the Securities Act all of the Registrable Securities that such Purchaser
has requested to be registered. However, the Corporation shall have no
obligation under this Section 7.3 to the extent that, with respect to a public
offering registration, any underwriter of such public offering reasonably
requests that the Registrable Securities or a portion thereof be excluded
therefrom. Notwithstanding the foregoing, nothing in this Section 7.3 shall
limit the Corporation's obligations under Section 7.2 above.

         7.4 Whenever required under this Section 7 to effect the registration
of any Registrable Securities, the Corporation shall, as expeditiously as
reasonably possible:

             (1) Prepare and file with the SEC a registration statement with
respect to such Registrable Securities and use its best efforts to cause such
registration to become effective and, to keep such registration statement
effective for so long as such Purchaser desires to dispose of the securities
covered by such registration statement or, if earlier, at such time as such
Purchaser could sell all of such Registrable Securities under Rule 144(k)
without limitation or delay. The registration statement (and each amendment or
supplement thereto, and each request for acceleration of effectiveness thereof)
shall be provided to (and subject to the approval of) the holders of the
Registrable Securities and their counsel at least 5 days prior to its filing or
other submission, which approval shall be promptly provided and shall not be
unreasonably withheld.

             (2) Prepare and file with the SEC such amendments and supplements
to such registration statements and the prospectus used in connection with such
registration statement as may be necessary to comply with the provisions of the
Securities Act with respect to the disposition of all securities covered by such
registration statement.

             (3) Furnish to the Purchasers such numbers of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Securities Act, and such other documents as the Purchasers
may reasonably request in order to facilitate the disposition of Registrable
Securities owned by the Purchasers.

             (4) Use its best efforts to register and qualify the securities
covered by such registration statement under such other securities or Blue Sky
laws of such jurisdictions as shall be reasonably requested by Purchasers,
provided that the Corporation shall not be required in connection therewith or
as a condition thereto to qualify to do business or to file a general consent to
service of process in any such states or jurisdictions.

             (5) Notify Purchasers of the happening of any event as a result of
which the prospectus included in such registration statement, as then in effect,
includes an untrue statement of material fact or omits to state a material fact
required to be stated therein or necessary to make the statements therein not
misleading in light of the circumstances then existing. In such an event, the
Corporation shall promptly file with the SEC all appropriate amendments and
supplements to such prospectus.

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             (6) Furnish, at the request of any Purchaser, an opinion of counsel
of the Corporation, dated the effective date of the registration statement, as
to the due authorization and issuance of the securities being registered and
compliance with securities laws by the Corporation in connection with the
authorization and issuance thereof.

             (7) Furnish to any Purchaser such copies of the Prospectus included
in the Registration Statement and any amendments and supplements as such
Purchaser shall reasonably request.

         7.5 Each Purchaser will furnish to the Corporation in connection with
any registration under this Section 7 such information regarding itself, the
Registrable Securities and other securities of the Corporation held by it, and
the intended method of disposition of such securities as shall be required to
effect the registration of the Registrable Securities held by such Purchaser.

         7.6 (i) The Corporation shall indemnify, defend and hold harmless each
holder of Registrable Securities which are included in a registration statement
pursuant to the provisions of this Section 7, Zesiger Capital Group LLC, any
underwriter (as defined in the Securities Act) for such holder, and the
directors, officers, members and controlling persons of, Zesiger Capital Group
LLC, such holder or underwriter from and against, and shall reimburse all of
them with respect to, any and all claims, suits, demands, causes of action,
losses, damages, liabilities, costs or expenses ("Liabilities") to which any of
them may become subject under the Securities Act or otherwise, arising from or
relating to (A) any untrue statement or alleged untrue statement of any material
fact contained in such registration statement, any prospectus contained therein
or any amendment or supplement thereto, or (B) the omission or alleged omission
to state therein a material fact required to be stated therein or necessary to
make the statements herein, in light of the circumstances in which they were
made, not misleading; provided, however, that the Corporation shall not be
liable in any such case to the extent that any such Liability arises out of or
is based upon an untrue statement or alleged untrue statement or omission or
alleged omission so made in conformity with information furnished by such person
in writing specifically for use in the preparation thereof.

             (ii) Each holder of Registrable Securities included in a
registration pursuant to the provision of this Section 7 shall indemnify, defend
and hold harmless the Corporation, its directors and officers, and shall
reimburse the Corporation its directors and officers with respect to, any and
all Liabilities to which any of them may become subject under the Securities Act
or otherwise, arising from or relating to (A) any untrue statement or alleged
untrue statement of any material fact contained in such registration statement,
any prospectus contained therein or any amendment or supplement thereto, or (B)
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 in which they were made, not misleading, in each case to the
extent, but only to the extent, that such untrue statement or alleged untrue
statement or omission or alleged omission was so made in reliance upon and in
strict conformity with written information furnished by or on behalf of such
holder specifically for use in the preparation thereof.

                                      -12-
<PAGE>   13

             (iii) Promptly after receipt by an indemnified party pursuant
to the provisions of Sections 7.6(i) or 7.6(ii) of notice of the commencement of
any action involving the subject matter of the foregoing indemnity provisions,
such indemnified party shall, if a claim thereof is to be made against the
indemnifying party pursuant to the provisions of Sections 7.6(i) or 7.6(ii),
promptly notify the indemnifying party of the commencement thereof; provided,
however, that the failure to so notify the indemnifying party shall not relieve
it from its indemnification obligations hereunder except to the extent that the
indemnifying party is materially prejudiced by such failure. If such action is
brought against any indemnified party and it notifies the indemnifying party of
the commencement thereof, the indemnifying party shall have the right to
participate in, and, to the extent that it may wish, jointly with any other
indemnifying party similarly notified, to assume the defense thereof, with
counsel satisfactory to such indemnified party; provided, however, if the
defendants in any action include both the indemnified party and the indemnifying
party and the indemnified party shall have reasonably concluded that there may
be legal defenses different from or in addition to those available to the
indemnifying party, or if there is conflict of interest which would prevent
counsel for the indemnifying party from also representing the indemnified party,
the indemnified party shall have the right to select separate counsel to
participate in the defense of such action on behalf of such indemnified party.
After notice from the indemnifying party to such indemnified party of its
election so to assume the defense thereof, the indemnifying party shall not be
liable to such indemnified party pursuant to Sections 7.6(i) or 7.6(ii) for any
expense of counsel subsequently incurred by such indemnified party in connection
with the defense thereof other than reasonable costs of investigation, unless
(A) the indemnified party shall have employed counsel in accordance with the
provisions of the preceding sentence, or (B) the indemnifying party shall not
have employed counsel satisfactory to the indemnified party to represent the
indemnified party within a reasonable time after the notice of the commencement
of the action. An indemnifying party shall not be responsible for amounts paid
in settlement without its consent, provided that its consent may not be
unreasonably withheld or delayed. No indemnifying party shall, without the
written consent of the indemnified party, effect the settlement or compromise
of, or consent to the entry of any judgment with respect to, any pending or
threatened action or claim in respect of which indemnification or contribution
may be sought hereunder (whether or not the indemnified party is an actual or
potential party to such action or claim) unless such settlement, compromise or
judgment (i) includes an unconditional release of the indemnified party from all
liability arising out of such action or claim and (ii) does not include a
statement as to or an admission of fault, culpability or a failure to act, by or
on behalf of any indemnified party.

         7.7 (i) With respect to the including of Registrable Securities in a
registration statement pursuant to this Section 7, all fees, costs and expenses
of and incidental to such registration, inclusion and public offering shall be
borne by the Corporation; provided, however, that any security holders
participating in such registration shall bear their pro rata share of the
underwriting discounts and commissions, if any.

             (ii) The fees, costs and expenses of registration to be borne
by the Corporation as provided in this Section 7.7 shall include, without
limitation, all registration, filing and NASD fees,

                                      -13-
<PAGE>   14

printing expenses, fees and disbursements of counsel and accountants for the
Corporation, fees and disbursements of one counsel to the Purchasers, and all
legal fees and disbursements and other expenses of complying with state
securities or Blue Sky laws of any jurisdiction or jurisdictions in which
securities to be offered are to be registered and qualified.

         7.8 The rights to cause the Corporation to register all or any portion
of Registrable Securities pursuant to this Section 7 may be assigned by the
Purchasers to a transferee or assignee of the Registrable Securities. Within a
reasonable time after such transfer the Purchasers shall notify the Corporation
of the name and address of such transferee or assignee and the securities with
respect to which such registration rights are being assigned. Such assignment
shall be effective only if immediately following such transfer the further
disposition of such securities by the transferee or assignee is restricted under
the Securities Act. Any transferee asserting registration rights hereunder shall
be bound by the provision of this Section 7.

         7.9 From and after the date of this Agreement, the Corporation shall
not agree to allow the holders of any securities of the Corporation to include
any of their securities in any registration statement filed by the Corporation
pursuant to Section 7.2 unless the inclusion of such securities will not reduce
the amount of the Registrable Securities included therein.

         7.10 In connection with any primary offering involving an underwriting
of shares of the Corporation's common stock, the Corporation shall not be
required under this Section 7 to include any Purchaser's securities in such
underwriting unless such Purchaser accepts the terms of the underwriting as
agreed upon between the Corporation and the underwriters selected by it, and
then only in such quantity as the underwriters determine in their sole
discretion will not jeopardize the success of the offering by the Corporation.

         7.11 The Corporation may suspend the effectiveness of a registration
statement required by this Section 7 for a period of not more than 30 days if
the Corporation is engaged in confidential negotiations or other confidential
business activities the disclosure of which (in the reasonable opinion of
outside counsel to the Corporation) would be required in such registration
statement and would not be required if such registration statement were not
filed and effective, and the Board of Directors of the Corporation determines in
good faith that such disclosure would be materially detrimental to the
Corporation and its stockholders, provided, however, that the Corporation shall
not utilize this right more than twice in any twelve-month period and not sooner
than 30 days after the prior use of such right. The Corporation will provide
simultaneous notice of any suspension to Zesiger Capital Group LLC.

                                   SECTION 8.

                    AFFIRMATIVE COVENANTS OF THE CORPORATION

         The Corporation hereby covenants that, during such time as any
Purchaser (or one of such Purchaser's affiliates)(for such purposes all shares
owned by all Zesiger Capital Group LLC clients

                                      -14-
<PAGE>   15

and principals will be aggregated as if a single purchaser) owns any shares of
Stock totaling in excess of 300,000 shares.

         8.1 Reports and Financial Statements

             (a) The Corporation will cause its common stock to continue to be
registered under Sections 12(b) or 12(g) of the Exchange Act, will comply in all
respects with its reporting and filing obligations under the Exchange Act, and
will not take any action or file any documents (whether or not permitted by the
Exchange Act or the rules thereunder) to terminate or suspend such registration
or to terminate or suspend its reporting and filing obligations under the
Exchange Act. The Corporation will take all action necessary to continue the
listing or trading of its common stock on any national securities exchange or
the Automated Quotation System of the National Association of Securities Dealers
on which such common stock is listed or traded, and will comply in all respects
with its reporting, filing and other obligations under the bylaws or rules of
said exchange or association.

             (b) The Corporation will furnish to such Purchaser for two years,
concurrently with the distribution or filing thereof, each annual and quarterly
report to its shareholders, its reports on Form 10K and 10Q, and each other
report, registration statement, definitive proxy statement or other document
filed with the SEC, and each press release or other public announcement issued
by the Corporation.

         8.2 MAINTENANCE OF OFFICE. The Corporation will maintain an office or
agency in the United States at such address as may be designated in writing from
time to time to the registered holders of the Stock, where notices,
presentations and demands to or upon the Corporation in respect of the Stock may
be given or made. Unless or until another office or agency is designated by the
Corporation, such office shall be at the address set forth adjacent to the name
of the Corporation at the foot of this Agreement.

         8.3 MAINTENANCE AND COMPLIANCE. The Corporation will (i) maintain its
corporate existence, rights, powers and privileges in good standing, (ii) comply
in all material respects with all laws and governmental regulations and
restrictions applicable to its business or properties, (iii) keep records and
books of account and maintain a system of internal accounting controls in
accordance with generally accepted accounting principles and in compliance with
Section 13(b)(2) of the Exchange Act, and (iv) retain independent public
accountants of recognized national standing as auditors of the Corporation's
annual financial statements.

         8.4 ASSIGNMENT OF RIGHTS. The rights of such Purchaser hereunder may be
assigned by such Purchaser in connection with the transfer or assignment of its
shares of Stock. Such rights may be further reassigned by each such transferee
to subsequent transferees. Any transferee asserting rights under this Agreement
shall be bound by its provisions.

                                      -15-

<PAGE>   16

         8.5 EFFECT OF COVENANTS. The covenants in Sections 8.1 and 8.3 shall
not be deemed to prohibit a merger, sale of all assets or other corporate
reorganization if (i) the entity surviving or succeeding to the Corporation is
bound by this Agreement with respect to its securities issued in exchange for or
replacement of the Stock, or (ii) the consideration received in exchange for or
replacement of the Stock is cash.

                                   SECTION 9.

                                 LEGEND ON STOCK

         Until the registration contemplated by Section 7 above is declared
effective with respect to the stock, each certificate representing the Stock
shall be stamped or otherwise imprinted with a legend substantially in the
following form (in addition to any legend required under any applicable state
securities laws):

THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR
ANY STATE SECURITIES LAWS. THEY MAY NOT BE SOLD OR OFFERED FOR SALE IN THE
ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT AS TO THE SECURITIES UNDER SAID
ACT AND ANY APPLICABLE STATE SECURITIES LAW OR AN OPINION OF COUNSEL
SATISFACTORY TO THE CORPORATION THAT SUCH REGISTRATION IS NOT REQUIRED.

         Upon request of a holder of Stock the Corporation shall remove the
foregoing legend or issue to such holder a new certificate therefor free of any
such legend, if the Corporation shall have received either an opinion of counsel
or a "no-action" letter of the SEC, in either case reasonable satisfactory in
substance to the Corporation and its counsel, to the effect that such legend is
no longer required.

                                   SECTION 10.

                                   ARBITRATION

         10.1 ARBITRATION

             10.1.1 SCOPE. Resolution of any and all disputes arising from or in
connection with this Agreement, whether based on contract, tort, common law,
equity, statute, regulation, order or otherwise ("Disputes"), including disputes
arising in connection with claims by third persons, shall be exclusively
governed by and settled in accordance with the provisions of this Section 10;
provided, that the foregoing shall not preclude equitable or other judicial
relief to enforce the provisions hereof or to preserve the status quo pending
resolution of Disputes hereunder.

             10.1.2 BINDING ARBITRATION. The parties hereby agree to submit all
Disputes to arbitration for final and binding resolution. Any party may initiate
such arbitration by delivery of a

                                      -16-
<PAGE>   17

demand therefor (the "Arbitration Demand") to the other parties. The arbitration
shall be conducted in the City of Wilmington, Delaware, by a panel of three
arbitrators, one chosen by each party and the third selected by agreement of the
parties not later than 10 days after delivery of the Arbitration Demand, or,
failing such agreement, appointed pursuant to the Commercial Arbitration Rules
of the America Arbitration Association, as amended from time to time (the "AAA
Rules"). If the arbitrators become unable to serve, his her or their
successor(s) shall be similarly selected or appointed.

             10.1.3 PROCEDURE. The arbitration shall be conducted pursuant to
the Federal Arbitration Act and such procedures as the parties may agree or, in
the absence of or failing such agreement, pursuant to the AAA Rules.
Notwithstanding the foregoing, (a) each party shall have the right to audit the
books and records of the other parties that are reasonably related to the
Dispute; (b) each party shall provide to the other, reasonably in advance of any
hearing, copies of all documents that a party intends to present in such
hearing; (c) all hearings shall be conducted on an expedited schedule; and (d)
all proceedings shall be confidential, except that either party may at its
expense make a stenographic record thereof.

             10.1.4 TIMING. The arbitrators shall complete all hearings not
later than 90 days after his or her selection or appointment, and shall make a
final award not later than 30 days thereafter. The arbitrators shall apportion
all costs and expenses of the arbitration, including the arbitrators' fees and
expenses, and fees and expenses of experts ("Arbitration Costs") between the
prevailing and non-prevailing party as the arbitrators shall deem fair and
reasonable. In circumstances where a Dispute has been asserted or defended
against on grounds that the arbitrator deems manifestly unreasonable, the
arbitrators may assess all Arbitration Costs against the non-prevailing party
and may include in the award the prevailing party's attorney's fees and expenses
in connection with any and all proceedings under this Section 10.
Notwithstanding the foregoing, in no event may the arbitrators award multiple or
punitive damages.

                                   SECTION 11.

                                  MISCELLANEOUS

         11.1 GOVERNING LAW. This Agreement shall be governed by and construed
in accordance with the laws of the State of Delaware. Except as set forth in
Section 10, any action or proceeding relating to this Agreement may be brought
in the courts of Delaware, or in the United States courts located in Delaware
and each of the parties irrevocably consents to the jurisdiction of such courts
in any such action or proceeding.

         11.2 SUCCESSORS AND ASSIGNS. Except as otherwise expressly provided
herein, the provisions hereof shall inure to the benefit of and be binding upon
the successors and assigns of the parties.

         11.3 ENTIRE AGREEMENT; AMENDMENT. This Agreement (including any
Exhibits and Schedules hereto) and the other documents delivered pursuant hereto
constitute the full and entire

                                      -17-

<PAGE>   18

understanding and agreement between the parties with regard to the subjects
hereof and thereof. Neither this Agreement nor any term hereof may be amended,
waived, discharged or terminated except by a written instrument signed by the
Corporation and holders of a majority of the Stock.

         11.4 NOTICES, ETC. All notices and other communications required or
permitted hereunder shall be mailed by internationally recognized courier
service and facsimile addressed (a) if to the Purchaser, as indicated below the
Purchaser's signature with a copy to the designated entity or at such other
address as the Purchaser shall have furnished to the Corporation in writing, or
(b) if to any other holder of any Stock at the address of such holder as shown
on the records of the Corporation, or (c) if to the Corporation, at its address
set forth below or at such other address as the Corporation shall have furnished
to the Purchaser and each such other holder in writing. All such notices or
communications shall be deemed given when delivered personally by courier, by
internationally recognized courier or by facsimile.

         11.5 DELAYS OR OMISSIONS. No delay or omission to exercise any right,
power or remedy accruing to any party to this Agreement (including any holder of
Stock), upon any breach or default or another party under this Agreement, shall
impair any such right, power or remedy of such party nor shall it be construed
to be a waiver of any such breach or default, or an acquiescence therein, or of
or in any similar breach or default thereafter occurring; nor shall any waiver
of any single breach or default be deemed a waiver of any other breach or
default theretofore or thereafter occurring. All remedies, either under this
Agreement or by law or otherwise afforded to any party, shall be cumulative and
not alternative.

         11.6 SEVERABILITY. In case any provision of this Agreement shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

                                      -18-
<PAGE>   19

         11.7 TITLES AND SUBTITLES. The titles of the Sections and subsections
of this Agreement are for convenience of reference only and are not be
considered in construing this Agreement.

         11.8 COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

         11.9 FEES AND EXPENSES. The parties hereto shall pay their own costs
and expenses in connection herewith, except that the Corporation shall pay to
the Purchasers up to $20,000 as and for all reasonable out-of-pocket expenses
incurred by such Purchasers in connection herewith, including the reasonable
fees and expenses of the Purchasers' counsel.

         IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed and delivered by their duly authorized officers as of the day and year
first written above.

                                    U.S. PLASTIC LUMBER CORPORATION

                                    By: /s/  Mark S. Alsentzer
                                       --------------------------------
                                       Name: Mark S. Alsentzer
                                       Title: CEO and President

                                    Address: 2300 Glades Road, Suite 440 West
                                             Boca Raton, FL 33431
                                             Fax # 561-394-5335

                                      -19-
<PAGE>   20

                                    The Purchasers listed on Schedule A

                                    By: /s/ Albert Zesiger
                                       --------------------------------
                                       Zesiger Capital Group LLC, as attorneys
                                       in fact for all Purchasers listed
                                       on Schedule A

                                    By: /s/ Albert Zesiger
                                       --------------------------------
                                       Name:
                                       Title:

                                    Address: 320 Park Ave., 30th Floor
                                             New York, NY  10022
                                             Attn: Albert L. Zesiger
                                             Fax #: 212-508-6399

                                      -20-
<PAGE>   21

                              Schedule B Purchaser

                                    Apodaca Investment Group

                                    By: /s/ Jerry C. Apodaca
                                       -----------------------------------
                                       Name: Jerry C. Apodaca
                                       Title: CEO

                                             Fax #: 415-675-7811
                                             Address: 50 California St.
                                             Suite 3315
                                             San Francisco, CA 94104

                                      -21-
<PAGE>   22

                              Schedule B Purchaser

                                    Apogee Fund, L.P.

                                    By: /s/ Michael C. Yeager
                                       -----------------------------------
                                       Name: Michael C. Yeager
                                       Title:

                                            Fax #:
                                            Address: 201 Main St.
                                                     Suite 1555
                                                     Ft. Worth, TX 76102

                                      -22-
<PAGE>   23

                              Schedule B Purchaser

                                    Zeke L.P.

                                    By: /s/  Edward N. Antoian
                                       -----------------------------
                                       Name: Edward N. Antoian
                                       Title: General Partner

                                            Fax #: 610-296-1430
                                            Address:
                                                        1235 Westlakes Dr.
                                                        Suite 330
                                                        Berwyn, PA 19312

                                      -23-
<PAGE>   24

                              Schedule B Purchaser

                                    Bulldog Capital Management

                                    By: /s/ Ronald Pollack
                                       -----------------------------
                                       Name: Ronald Pollack
                                       Title: Chairman

                                            Fax #: 727-442-6093
                                            Address:
                                                      Bulldog Capital Management
                                                      33 North Garden Ave.
                                                      Suite 750
                                                      Clearwater, FL  33755

                                      -24-
<PAGE>   25

                              Schedule B Purchaser

                                    Macuard Cook & Cie S.A.

                                    By: /s/
                                       -----------------------------
                                       Name:
                                       Title:

                                       Fax #: 011-41-22-716-3676
                                       Address:
                                                7, rue des Alpes
                                                Case postale 1380
                                                CH-12121 Geneve 1

<PAGE>   26

                              Schedule B Purchaser

                                    Stuart G. Gould

                                    By: /s/ Stuart G. Gould
                                       -----------------------------
                                       Name: Stuart G. Gould
                                       Title:

                                       Fax #: 805-563-0176
                                       Address:
                                                3916 State St.
                                                Suite 200
                                                Santa Barbara, CA 93105

                                      -25-
<PAGE>   27

                              Schedule B Purchaser

                                    Fidelity National Title Insurance

                                    By: /s/ Stuart G. Gould
                                       -----------------------------
                                       Name: Stuart G. Gould
                                       Title: Vice President

                                       Fax #: 805-563-0176
                                       Address:
                                                3916 State St.
                                                Suite 200
                                                Santa Barbara, CA 93105

                                      -26-
<PAGE>   28

                              Schedule B Purchaser

                                    G.A. Wetterstein

                                    By: /s/ Gregory A. Wetterstein
                                       -------------------------------
                                       Name: Gregory A. Wetterstein
                                       Title: General Partner

                                       Fax #: 415-461-0691
                                       Address:
                                               17 E. Sir Francis Drake Blvd.
                                               Suite 100
                                               Larkspur, CA 94939

                                      -27-
<PAGE>   29

                              Schedule B Purchaser

                                    Hollis Capital Partners

                                    By: /s/ Paul J. Siegel
                                       --------------------------------
                                       Name: Paul J. Siegel
                                       Title:

                                       Fax #: 415-288-2323
                                       Address: One Sansome St.
                                                San Francisco, CA 9411

                                      -28-
<PAGE>   30

                              Schedule B Purchaser

                                    Apex Limited Partners, L.P.

                                    By: /s/ Devin Wate
                                       --------------------------------
                                       Name: Devin Wate
                                       Title: Managing Partner

                                       Fax #: 425-391-7045
                                       Address:
                                                26339 SE 33 St.
                                                Issaquah, WA 98029

                                      -29-

<PAGE>   31

                              Schedule B Purchaser

                                    EDJ Limited

                                    By: /s/ Jeffrey H. Porter
                                       -----------------------------
                                       Name: Jeffrey H. Porter
                                       Title: Investment Advisor

                                       Fax #: 415-332-8223
                                       Address:
                                               100 Shoreline, Suite 2118
                                               Mill Valley, CA 94965

                                      -30-
<PAGE>   32

                              Schedule B Purchaser

                                    Verita SG Investment Trust

                                    By: /s/ V. Ziegesar
                                       ------------------------------
                                       Name: V. Ziegesar
                                       Title: CEO

                                       Fax #: 011-49-69-97574-330
                                       Address:
                                               Bettinastr. 62
                                               60325 Frankfurt
                                               Germany

                                      -31-
<PAGE>   33

                              Schedule B Purchaser

                                    Wentworth Hauser & Violich, Inc.
                                    FBO Stichting Pensioenfonds ABP

                                    By: /s/ Phil Fox
                                       ------------------------------
                                       Name: Phil Fox
                                       Title: Managing Director

                                       Fax #:415-788-7281
                                       Address:
                                                333 Sacramento St.
                                                San Francisco, CA 94111

                                      -32-
<PAGE>   34

                              Schedule B Purchaser

                                    Clarion Capital Corporation

                                    By: /s/ Thomas Wieham
                                       ------------------------------
                                       Name: Thomas Wieham
                                       Title: Treasurer

                                       Fax #: 216-694-3545
                                       Address:
                                               20 Redground Rd.
                                               Old Westbury, NY 11568

                                      -33-<PAGE>   1

                                                                     EXHIBIT 4.1

COMMON STOCK                                    THIS CERTIFICATE IS TRANSFERABLE
                          [EMBLEM]                  IN NEW YORK, NEW YORK OR
[NOVA LOGO]                                         CHARLOTTE, NORTH CAROLINA

                                                     INCORPORATED UNDER THE LAWS
                                                       OF THE STATE OF GEORGIA

                                                               CUSIP 669784 10 0
                                                               SEE REVERSE FOR
                                                             CERTAIN DEFINITIONS

                           NOVA CORPORATION (GEORGIA)
                               [NOVA CERTIFICATE]

            FULLY PAID AND NONASSESSABLE SHARES OF THE COMMON STOCK
                          PAR VALUE $.01 PER SHARE OF

     NOVA Corporation, transferable on the books of the Corporation in person
     or by duly authorized attorney upon surrender of this Certificate properly
     endorsed.

     This Certificate and the shares of stock represented hereby are issued
     and shall be held subject to all of the provisions of the Articles of
     Incorporation of the Corporation and all amendments thereto (copies of
     which are on file with the Transfer Agent), to all of which the holder by
     acceptance hereof assents. This Certificate is not valid until
     countersigned by the Transfer Agent and registered by the Registrar.

     Witness the facsimile seal of the Corporation and the facsimile signatures
     of its duly authorized officers.

COUNTERSIGNED AND REGISTERED:                 /s/ xxxxxxxxxxxxxxxxxxxxxxxxx
FIRST UNION NATIONAL BANK                        ------------------------------
(CHARLOTTE, NC)        TRANSFER AGENT               Chairman, President and
                        AND REGISTRAR                 Chief Executive Officer

BY                                            /s/ xxxxxxxxxxxxxxxxxxxxxxxxx
                                                 -------------------------------
                 AUTHORIZED SIGNATURE                Senior Vice President,
                                                  General Counsel and Secretary

<PAGE>   2
         This certificate also evidences and entitles the holder hereof to
certain Rights as set forth in the Rights Agreement between NOVA Corporation
(the "Company") and First Union National Bank (the "Rights Agent") dated as
of July 9, 1999 (the "Rights Agreement"), the terms of which are hereby
incorporated herein by reference and a copy of which is on file at the principal
offices of the Company. Under certain circumstances, as set forth in the Rights
Agreement, such Rights will be evidenced by separate certificates and will no
longer be evidenced by this certificate. The Company will mail to the holder of
this certificate a copy of the Rights Agreement, as in effect on the date of
mailing, without charge promptly after receipt of a written request therefor.
Under certain circumstances set forth in the Rights Agreement, Rights issued to,
or held by, any Person who is, was or becomes an Acquiring Person, or any
Affiliate or Associate thereof (as such terms are defined in the Rights
Agreement), whether currently held by or on behalf of such Person or by any
subsequent holder, may become null and void.

THE CORPORATION WILL FURNISH TO ANY SHAREHOLDER, UPON REQUEST AND WITHOUT
CHARGE, A FULL STATEMENT OF THE DESIGNATIONS, PREFERENCES, LIMITATIONS AND
RELATIVE RIGHTS OF THE SHARES OF EACH CLASS AUTHORIZED TO BE ISSUED AND THE
VARIATIONS IN THE RELATIVE RIGHTS AND PREFERENCES BETWEEN THE SHARES OF EACH
SUCH SERIES SO FAR AS THE SAME HAVE BEEN FIXED AND DETERMINED. THE ARTICLES OF
INCORPORATION OF THE CORPORATION PROVIDE THAT THE PREFERRED STOCK MAY BE ISSUED,
IN ONE OR MORE SERIES, THE RELATIVE RIGHTS AND PREFERENCES OF WHICH MAY BE FIXED
AND DETERMINED BY THE BOARD OF DIRECTORS FROM TIME TO TIME.

                                NOVA CORPORATION

     The following abbreviations, when used in the inscription on the face of
this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

<TABLE>
<C>                                          <C>
TEN COM - as tenants in common               UNIF GIFT MIN ACT -           Custodian
TEN ENT - as tenants by the entireties                           ---------           ----------
JT TEN  - as joint tenants with right of                          (Cust)              (Minor)
          survivorship and not as tenants                        under Uniform Gifts to Minors
          in common                                              Act
                                                                     --------------------------
                                                                             (State)
</TABLE>
    Additional abbreviations may also be used though not in the above list.

For value received,                        hereby sell, assign and transfer unto
                    ----------------------

PLEASE INSERT SOCIAL SECURITY OR OTHER
    IDENTIFYING NUMBER OF ASSIGNEE
[                                 ]

------------------------------------------------------------------------------
 (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE OF ASSIGNEE)

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

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

------------------------------------------------------------------------------
shares of the capital stock represented by the within Certificate, and do
hereby irrevocably constitute and appoint

--------------------------------------------------------------------  Attorney
to transfer the said stock on the books of the within named Corporation with
full power of substitution in the premises.

Dated
      ----------------------

                       NOTICE:
                               -------------------------------------------------
                               THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND
                               WITH THE NAME AS WRITTEN UPON THE FACE OF THE
                               CERTIFICATE IN EVERY PARTICULAR, WITHOUT
                               ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.

                       SIGNATURE(S) GUARANTEED:

                               -------------------------------------------------
                               THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN
                               ELIGIBLE GUARANTOR INSTITUTION (BANKS,
                               STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND
                               CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED
                               SIGNATURE GUARANTEE MEDALLION PROGRAM). PURSUANT
                               TO S.E.C. RULE 17Ad-15.

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00006-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00006-of-00352.parquet"}]]