Stockholders Agreement

STOCKHOLDERS AGREEMENT


STOCKHOLDERS AGREEMENT dated as of August 22, 1997 among Cambrex Corporation, a Delaware corporation ("Parent"), BW Acquisition Corporation, a Delaware corporation ("Purchaser") and ANASCO GmbH, a German limited liability company ("Stockholder").


WHEREAS, concurrently herewith Parent, the Purchaser, and BioWhittaker, Inc., a Delaware corporation (the "Company"), are entering into an Agreement and Plan of Merger of even date herewith (as such agreement may be amended from time to time, the "Merger Agreement"; capitalized terms used but not otherwise defined herein shall have the respective meanings ascribed to them in the Merger Agreement) pursuant to which the Purchaser will be merged with and into the Company (the "Merger"); and


WHEREAS, in furtherance thereof, the Parent proposes that the Purchaser make an offer (the "Offer") to purchase for cash all of the issued and outstanding shares of common stock of the Company, and all associated rights to purchase preferred stock, at a price of $11.625 per share net to the seller;


WHEREAS, Parent has required, as a condition to its entering into the Merger Agreement and commencing the Offer, that Stockholder enter into, and Stockholder has agreed to enter into, this Agreement.


NOW, THEREFORE, to satisfy this condition and in consideration of Parent's entering into the Merger Agreement and causing the Offer to be commenced, respectively, and in consideration of the premises and the representations, warranties and covenants contained herein, the parties agree as follows:


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1. Representations and Warranties of Stockholder. Stockholder hereby represents and warrants to Parent as follows:


(a) Ownership of Shares. (i) Stockholder is the record holder
and beneficial owner of the number of shares of the common stock of the
Company, par value $.01 per share (the "Company Common Stock"), set
forth opposite Stockholder's name on Schedule A hereto (the "Existing
Shares", and together with any shares of Company Common Stock acquired
by Stockholder after the date hereof and prior to the termination
hereof, whether upon exercise of options or warrants, conversion of
convertible securities, purchase, exchange or otherwise, the "Shares").


(ii) On the date hereof, the Existing Shares set forth
opposite Stockholder's name on Schedule A constitute all of the shares
of Company Common Stock owned by Stockholder.


(iii) Stockholder has (A) sole power of disposition; (B) sole
voting power; and (C) sole power to demand dissenter's or appraisal
rights, in each case with respect to all of Stockholder's Existing
Shares and with no restrictions on such rights, subject to applicable
federal securities laws and the terms of this Agreement.


(b) Power; Binding Agreement. Stockholder has all requisite
legal capacity, power and authority to enter into and perform all of
Stockholder's obligations under this Agreement. The execution, delivery
and performance of this Agreement by Stockholder will not violate any
other agreement to which Stockholder is a party or by which Stockholder
is bound including, without limitation, any voting agreement,
stockholders agreement, voting trust or other agreement. This Agreement
has been duly and validly authorized, executed and delivered by
Stockholder and constitutes a valid and binding agreement of
Stockholder, enforceable


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against Stockholder in accordance with its terms, except as such
enforceability may be limited by bankruptcy, insolvency, moratorium or
other similar laws affecting or relating to the enforcement of
creditors' rights generally or by general principles of equity. There
is no beneficiary of or holder of a voting trust certificate whose
consent is required for the execution and delivery of this Agreement or
the consummation of the transactions contemplated hereby.


(c) No Conflicts. Except for filing under the
Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the
"HSR Act"), if applicable, (i) no filing with, and no permit,
authorization, consent or approval of, any state or federal public body
or authority is necessary for the execution of this Agreement by
Stockholder and the consummation by Stockholder of the transactions
contemplated hereby and (ii) neither the execution and delivery of this
Agreement by Stockholder nor the consummation by Stockholder of the
transactions contemplated hereby nor compliance by Stockholder with any
of the provisions hereof shall (A) conflict with or result in any
breach of the applicable organization documents applicable to
Stockholder, (B) result in a material violation or breach of, or
constitute (with or without notice or lapse of time or both) a default
(or give rise to any third party right of termination, cancellation,
modification, prepayment or acceleration) under any of the terms,
conditions or provisions of any material note, bond, mortgage,
indenture, license, contract, commitment, arrangement, understanding,
agreement or other instrument or obligation of any kind to which
Stockholder is a party or by which such Stockholder or any of such
Stockholder's properties or assets may be bound or (C) violate any
order, writ, injunction, decree, judgment, statute, rule, regulation or
governmental permit or license (collectively, "Laws") applicable to
Stockholder or any of such Stockholder's properties or assets.


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(d) Stockholder's Shares and the certificates representing
Shares are now and at all times during the term hereof will be held by
Stockholder, or by a nominee or custodian for the benefit of
Stockholder, free and clear of all liens, claims, security interests,
proxies, voting trusts or agreements, understandings, arrangements or
any other encumbrances whatsoever, except for any such encumbrances or
proxies arising hereunder.


(e) No broker, investment banker, financial adviser or other
Person is entitled to any broker's, finder's, financial adviser's or
other similar fee or commission payable by Parent or Purchaser in
connection with the transactions contemplated hereby based upon
arrangements made by or on behalf of Stockholder.


(f) Stockholder understands and acknowledges that Parent is
entering into the Merger Agreement in reliance upon Stockholder's
execution and delivery of this Agreement.


2. Agreement to Tender. Stockholder hereby irrevocably agrees to duly tender all of the Shares of Stockholder pursuant to the terms of the Offer and not to withdraw such Shares prior to the expiration of the Offer.


3. Agreement to Vote; Proxy.


(a) Voting. Stockholder hereby agrees that, during the time this Agreement is in effect, at any meeting of the stockholders of the Company, however called, or in connection with any written consent of the stockholders of the Company, Stockholder shall vote (or cause to be voted) the Shares of Stockholder (i) in favor of the Merger, the execution and delivery by the Company of the Merger Agreement and the approval of the terms thereof and each of the other actions contemplated by the Merger Agreement and this Agreement and any actions required in furtherance hereof and thereof; (ii) against any action or agreement that would result in a breach of any covenant, representa-


4 5 tion or warranty or any other obligation or agreement of the Company under the Merger Agreement, the Offer or this Agreement; and (iii) except as specifically requested in writing by Parent in advance, against the following actions (other than the Merger and the transactions contemplated by the Merger Agreement): (A) any extraordinary corporate transaction, such as a merger, consolidation or other business combination involving the Company or its subsidiaries; (B) a sale, lease or transfer of a material amount of assets of the Company or its subsidiaries or a reorganization, recapitalization, dissolution, liquidation or winding up of the Company or any of its subsidiaries; (C) any change in the majority of the board of directors of the Company; (D) any material change in the present capitalization of the Company or any amendment of the Company's Certificate of Incorporation; (E) any other material change in the Company's corporate structure or business; and (F) any other action which is intended or could reasonably be expected to impede, interfere with, delay, postpone, ...