<PAGE>
Exhibit 4.2
THESE SECURITIES AND THE SECURITIES ISSUABLE UPON EXERCISE OF THESE SECURITIES
HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
"ACT"), AND THEY MAY NOT BE OFFERED, SOLD, PLEDGED, HYPOTHECATED, ASSIGNED OR
TRANSFERRED EXCEPT (i) PURSUANT TO A REGISTRATION STATEMENT UNDER THE ACT WHICH
HAS BECOME EFFECTIVE AND IS CURRENT WITH RESPECT TO THESE SECURITIES, OR (ii)
PURSUANT TO A SPECIFIC EXEMPTION FROM REGISTRATION UNDER THE ACT BUT ONLY UPON A
HOLDER HEREOF FIRST HAVING OBTAINED THE WRITTEN OPINION OF COUNSEL TO THE
COMPANY, OR OTHER COUNSEL REASONABLY ACCEPTABLE TO THE COMPANY, THAT THE
PROPOSED DISPOSITION IS CONSISTENT WITH ALL APPLICABLE PROVISIONS OF THE ACT AS
WELL AS ANY APPLICABLE "BLUE SKY" OR SIMILAR STATE SECURITIES LAW.
December 1, 1999
BOSTON LIFE SCIENCES, INC.
Warrant for the Purchase of Shares of
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Common Stock
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No. BLSI - [INSERT NUMBER] [INSERT NUMBER] Shares
FOR VALUE RECEIVED, BOSTON LIFE SCIENCES, INC., A Delaware corporation (the
"Company"), hereby certifies that [INSERT NAME] or its permitted assigns, is
entitled to purchase from the Company, at any time or from time to time
commencing on the date hereof (the "Initial Exercise Date") and prior to 5:00 P.
M., New York City time, on December 1, 2004 (the "Termination Date", such date
to be 5 years subsequent to the Initial Exercise Date), [INSERT NUMBER] fully
paid and non-assessable shares of the Common Stock, $.01 par value per share, of
the Company for an aggregate purchase price of [INSERT PRICE]computed on the
basis of $6.00 per share. (Hereinafter, (i) said Common Stock, together with any
other equity securities which may be issued by the Company with respect thereto
or in substitution therefor, is referred to as the "Common Stock", (ii) the
shares of the Common Stock purchasable hereunder or under any other Warrant (as
hereinafter defined) are referred to as the "Warrant Shares", (iii) the
aggregate purchase price payable for the Warrant Shares hereunder is referred to
as the "Aggregate Warrant Price", (iv) the price payable for each of the Warrant
Shares hereunder is referred to as the "Per Share Warrant Price", (v) this
Warrant, all similar Warrants issued on the date hereof and all warrants
hereafter issued in exchange or substitution for this Warrant or such similar
Warrants are referred to as the "Warrants" and (vi) the holder of this Warrant
is referred to as the "Holder" and the holder of this Warrant and all other
Warrants or Warrant Shares issued upon the exercise of any Warrant are referred
to as the "Holders"). The Aggregate Warrant Price is not subject to adjustment.
The Per Share Warrant Price is subject to adjustment as hereinafter provided; in
the event of any such adjustment, the number of Warrant Shares shall be adjusted
by dividing the Aggregate Warrant Price by the Per Share Warrant Price in effect
immediately after such adjustment.
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1. Exercise of Warrant
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(a) This Warrant may be exercised, in whole at any time or in part
from time to time, commencing on the Initial Exercise Date and prior to 5:00 P.
M. New York City time, on the Termination Date by the holder by the surrender of
this Warrant (with the subscription form at the end hereof duly executed) at the
address set forth in Subsection 10(a) hereof, together with proper payment of
the Aggregate Warrant Price, or the proportionate part thereof if this Warrant
is exercised in part, with payment for Warrant Shares made by certified or
official bank check payable to the order of the Company.
(b) If this Warrant is exercised in part, this Warrant must be
exercised for a number of whole shares of the Common Stock and the Holder is
entitled to receive a new Warrant covering the Warrant Shares which have not
been exercised and setting forth the proportionate part of the Aggregate Warrant
Price applicable to such Warrant Shares. Upon surrender of this Warrant, the
Company will instruct its transfer agent to (i) issue a certificate or
certificates in the name of the Holder for the largest number of whole shares of
the Common Stock to which the Holder shall be entitled and, if this Warrant is
exercised in whole, in lieu of any fractional share of the Common Stock to which
the Holder shall be entitled, pay to the Holder cash in an amount equal to the
fair value of such fractional share (determined in such reasonable manner as the
Board of Directors of the Company shall determine), and (ii) deliver the other
securities and properties receivable upon the exercise of this Warrant, if any,
or the proportionate part thereof if this Warrant is exercised in part, pursuant
to the provisions of this Warrant.
2. Reservation of Warrant Shares; Listing. The Company agrees that,
--------------------------------------
prior to the expiration of this Warrant, the Company will at all times (a) have
authorized and in reserve, and will keep available, solely for issuance or
delivery upon the exercise of this Warrant, the shares of the Common Stock,
including other securities and properties as from time to time shall be
receivable upon the exercise of this Warrant, free and clear of all restrictions
on sale or transfer, except for the restrictions on sale or transfer set forth
in the Securities Act of 1933, as amended (the "Act"), and free and clear of all
preemptive rights and rights of first refusal; and (b) if the Company prepares
and files a registration statement covering the shares of Common Stock issued or
issuable upon exercise of this Warrant with the Securities and Exchange
Commission (the "SEC") which registration statement is declared effective by the
SEC under the Act and the Company lists its Common Stock on any national
securities exchange, it will use its best efforts to cause the shares of Common
Stock to this Warrant to be listed on such exchange.
3. Restriction on Transfer; Registration Under the Securities Act of
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1933, as amended.
-----------------
(a) Neither this Warrant nor any Shares issuable upon exercise hereof
has been registered under the Securities Act of 1933, as amended (the "Act"),
and none of such securities may be offered, sold, pledged, hypothecated,
assigned or transferred except (i) pursuant to a registration statement under
the Act which has become effective and is current with respect to such
securities, or (ii) pursuant to a specific exemption from registration under the
Act but only upon a Holder hereof first having obtained the written opinion of
counsel to the Company, or other counsel reasonably acceptable to the Company,
that the proposed disposition is consistent with all applicable provisions of
the Act as well as any applicable "Blue Sky" or similar state securities law.
Upon exercise, in part or in whole, of this Warrant, each certificate issued
representing the Shares underlying this Warrant shall bear a legend to the
foregoing effect.
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(b) Within one hundred eighty (180) days following the issuance of
this Warrant, the Company shall prepare and file with the SEC, a registration
statement and such other documents, including a prospectus, as may be necessary
in the opinion of counsel for the Company in order to comply with the provisions
of the Act so as to permit a public offering and sale of the Warrant Shares by
the Holder(s) for a consecutive period of two years or until the distribution
described in the registration statement has been completed, whichever is
shorter, provided that, for not more than thirty (30) consecutive Trading Days
(or not more than sixty (60) consecutive Trading Days if the event giving rise
thereto is an acquisition required to be reported in a Current Report on Form 8-
K pursuant to Item 2 thereof) or for a total of not more than ninety (90)
Trading Days in any twelve (12) month period, the Company may delay the
disclosure of material non-public information concerning the Company (as well as
prospectus or registration statement updating) the disclosure of which at the
time is not, in the good faith opinion of the Company, in the best interests of
the Company (an "Allowed Delay"); provided, further, that the Company shall
promptly (i) notify the undersigned in writing of the existence of (but in no
event, without the prior written consent of the undersigned, shall the Company
disclose to such undersigned any of the facts or circumstances regarding)
material non-public information giving rise to an Allowed Delay and (ii) advise
the undersigned in writing to cease all sales under such registration statement
until the end of the Allowed Delay. The Company shall use its best efforts to
cause the registration statement to become effective at the earliest possible
time. "Trading Day" shall mean a day on which the national securities exchange
or NASDAQ used to determine the Closing Bid Price is open for the transaction of
business or the reporting of trades or, if the Closing Bid Price is not so
determined, a day on which NASDAQ is open for the transaction of business.
(c) The Company agrees that if, at any time during the period
commencing on the date hereof and ending on the Termination Date, the Holder
and/or the Holders of any other Warrants and Warrant Shares which have not
previously been registered under the Act or which are not freely transferable
without registration under the Act due to the lapse of time or otherwise and who
or which shall hold greater than 65% of the Warrant Shares issued or issuable
upon the exercise of the Warrants, shall request that the Company file a
registration statement under the Act covering not less than 65% of the shares of
the Warrant Shares issued or issuable upon the exercise of the Warrants, the
Company will (i) promptly notify each Holder of the Warrants and each holder of
Warrant Shares that such registration statement will be filed and that the
Warrant Shares which are then held, and/or may be acquired upon exercise of the
Warrants by the Holder and such holders will be included in such registration
statement at the Holder's and such holders' request, (ii) cause such
registration statement to cover all such Warrant Shares which it has been so
requested to include, (iii) use its best efforts to cause such registration
statement to become effective as soon as practicable and (iv) take all other
action necessary under any Federal or state law or regulation of any
governmental authority to permit all such Common Stock which it has been so
requested to include in such registration statement to be sold or otherwise
disposed of, and will use its best efforts to maintain such compliance with each
such Federal and state law and regulation of any governmental authority for the
period necessary for such Holders to effect the proposed sale of other
disposition; provided, however, that such period and the period during which the
Company is required to keep the registration statement effective in connection
with this Section shall not exceed the earlier of (A) 120 days from the date of
effectiveness of such registration statement under the Act and (B) the date upon
which the Holders have completed the sale or other disposition of the Warrant
Shares. The Company shall be required to effect a registration or qualification
pursuant to this Subsection on one occasion only.
(d) The Company agrees that if, at any time and from time to time
during the period commencing on the date hereof and ending on the Termination
Date, the Board of
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<PAGE>
Directors of the Company shall authorize the filing of a registration statement
under the Act, other than a registration statement on Form S-8, S-4 or other
form which does not include substantially the same information as would be
required in a form for the general registration of securities) in connection
with the proposed offer of any of its securities by it or any of its
stockholders, the Company will (i) promptly notify each Holder of the Warrants
and each holder of Warrant Shares that such registration statement will be filed
and that the Warrant Shares which are then held, and/or may be acquired upon
exercise of the Warrants by the Holder and such holders will be included in such
registration statement at the Holder's and such holders' request, (ii) cause
such registration statement to cover all of such Common Stock which it has been
so requested to include, (iii) use its best efforts to cause such registration
statement to become effective as soon as practicable and (iv) take all other
action necessary under any Federal or state law or regulation of any
governmental authority to permit all such Common Stock which it has been so
requested to include in such registration statement to be sold or otherwise
disposed of, and will use its best efforts to maintain such compliance with each
such Federal and state law and regulation of any governmental authority for the
period necessary for the Holder and such Holders to effect the proposed sale or
other disposition; provided, however, that such period and the period during
which the Company is required to keep the registration statement effective in
connection with this Section shall not exceed the earlier of (A) 120 days from
the date of effectiveness of such registration statement under the Act and (B)
the date upon which the Holders have completed the sale or other disposition of
the Warrant Shares; provided, further, however that such period shall be
extended for a period of time, not to exceed 120 days, equal to the period the
Holders refrain from selling or disposing of any Warrant Shares in such
registration at the request of the underwriter.
Whenever the Company is required pursuant to the provisions of this Section
3 to include in a registration statement Warrant Shares, the Company shall (i)
furnish each Holder of any such Warrant Shares and each underwriter of such
Common Stock with such copies of the prospectus, including the preliminary
prospectus, conforming to the Act (and such other documents as each such Holder
or each such underwriter may reasonably request) in order to facilitate the sale
or distribution of such Common Stock, (ii) use its best efforts to register or
qualify such Common Stock under the blue sky laws (to the extent applicable) of
such jurisdiction or laws (to the extent applicable) of such jurisdiction or
jurisdictions as the Holders of any Common Stock and each underwriter of such
Common Stock being sold by such Holders shall reasonably request and (iii) take
such other actions as may be reasonably necessary or advisable to enable such
Holders and such underwriters to consummate the sale or distribution in such
jurisdiction or jurisdictions in which such Holders shall have reasonably
requested that such Common Stock be sold; provided, however that the foregoing
"piggyback" registration right shall be subject to the cutback in the sole
discretion of the underwriter for the Company.
(e) In connection with any registration under Section 3 hereof, the
Company covenants and agrees as follows:
(i) The Company shall furnish each Holder desiring to sell its
securities such number of prospectuses as shall reasonably be requested.
(ii) The Company shall pay all costs (excluding fees and expenses
of Holder(s)' counsel and any underwriting or selling commissions or other
charges of any broker-dealer acting on behalf of Holder(s)), fees and
expenses in connection with all registration statements filed pursuant to
Sections 3 hereof including, without limitation, the Company's legal and
accounting fees, printing expenses, and blue sky fees and expenses.
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(iii) The Company will take all necessary action which may be
required in qualifying or registering the Warrant Shares and any other
securities issuable upon exercise of the Warrants included in a
registration statement for offering and sale under the securities or blue
sky laws of such states as are reasonably requested by the Holder(s),
provided that the Company shall not be obligated to qualify as a foreign
corporation to do business under the laws of any such jurisdiction.
(iv) The Company shall indemnify the Holder(s) of the Warrant
Shares to be sold pursuant to any registration statement and each person,
if any, who controls such Holders within the meaning of Section 15 of the
Act or Section 20(a) of the Securities and Exchange Act of 1934, as amended
("Exchange Act"), against all loss, claim, damage, expense or liability
(including all expenses reasonably incurred in investigating, preparing or
defending against any claim whatsoever) to which any of them may become
subject under the Act, the Exchange Act or any other statute, common law or
otherwise, arising out of or based upon any untrue statement or alleged
untrue statement of a material fact contained (x) in such registration
statement (as from time to time amended or supplemented); (y) in any post-
effective amendment or amendments; or (z) in any application or other
document or written communication (in this Section 3 collectively called an
application) executed by the Company or based upon written information
furnished by the Company filed in any jurisdiction in order to qualify the
Warrant Shares under the securities laws thereof or filed with the
Commission, any state securities commission or agency, the American Stock
Exchange, the National Association of Securities Dealers, Inc., The Nasdaq
Stock Market or any securities exchange, or the omission or alleged
omission therefrom of a material fact required to be stated therein or
necessary to make the statements contained therein not misleading, unless
such statement or omission was made in reliance upon and in conformity with
written information furnished to the Company by the Holder(s) expressly for
use in such registration statement, any amendment or supplement thereto or
any application, as the case may be. If any action is brought against the
Holder(s) or any controlling person of the Holder(s) in respect of which
indemnity may be sought against the Company pursuant to this Section
3.e.(iv), the Holder(s) or such controlling person shall within thirty (30)
days after the receipt thereby of a summons or complaint notify the Company
in writing of the institution of such action and the Company shall assume
the defense of such action, including the employment and payment of
reasonable fees and expenses of counsel (which counsel shall be reasonably
satisfactory to the Holder(s) or such controlling person), but the failure
to give such notice shall not affect such indemnified person's right to
indemnification hereunder except to the extent that the Company's defense
of such action was materially adversely affected thereby. The Holder(s) or
such controlling person shall have the right to employ its or their own
counsel in any such case, but the fees and expenses shall be at the expense
of the Holder(s) or such controlling person unless the employment of such
counsel shall have been authorized in writing by the Company. Except as
expressly provided above, in the event that the Company shall not
previously have assumed the defense of any such action or claim, the
Company shall not thereafter be liable to the Holder(s) or such controlling
person in investigating, preparing or defending any such action or claim.
The Company agrees promptly to notify the Holder(s) of the commencement of
any litigation or proceedings against the Company or any of its officers,
directors or controlling persons in connection with the resale of the
Warrant Securities or in connection with such registration statement.
(v) The Holder(s) of the Warrant Shares to be sold pursuant to
a registration statement, and their successors and assigns, shall
severally, and not jointly, indemnify the Company, its officers and
directors and each person, if any, who controls the Company
5
<PAGE>
within the meaning of Section 15 of the Act or Section 20(a) of the
Exchange Act, against all loss, claim, damage or expense or liability
(including all expenses reasonably incurred in investigating, preparing or
defending against any claim whatsoever) to which they may become subject
under the Act, the Exchange Act or otherwise, arising from information
furnished in writing by or on behalf of such Holders, or their successors
or assigns, for specific inclusion in such registration statement. The
Holder(s) further agree(s) that upon demand by an indemnified person, at
any time or from time to time, they will promptly reimburse such
indemnified person for any loss, claim, damage, liability, cost or expense
actually and reasonably paid by the indemnified person as to which the
Holder(s) have indemnified such person pursuant hereto. Notwithstanding the
foregoing provisions of this Section 3.e.(v), any such payment or
reimbursement by the Holder(s) of fees, expenses or disbursements incurred
by an indemnified person in any proceeding in which a final judgment by a
court of competent jurisdiction (after all appeals or the expiration of
time to appeal) is entered against the Company or such indemnified person
as a direct result of the Company or such person's gross negligence or
willful misfeasance will be promptly repaid to the Holder(s).
(vi) Nothing contained in this Agreement shall be construed as
requiring the Holder(s) to exercise their Warrants prior to the initial
filing of any registration statement or the effectiveness thereof.
(vii) If the offering in which these securities were acquired is
an underwritten public offering, and the underwriter so requests, the
Company shall furnish to each holder of shares participating in the
offering and to each underwriter, if any, and the Placement Agent, a signed
counterpart, addressed to such holder or underwriter, if any, and the
Placement Agent, of (i) an opinion of counsel to the Company dated the date
of the closing under the underwriting agreement, and (ii) a "cold comfort"
letter dated the date of the closing under the underwriting agreement
signed by the independent public accountants who have issued a report on
the company's financial statements included in such registration statement,
in each case covering substantially the same matters with respect to such
registration statement (and the prospectus included therein) and, in the
case of such accountants' letter with respect to events subsequent to the
date of such financial statements, as are customarily covered in opinions
of issuer's counsel and in accountants' letters delivered to underwriters
in underwritten public offerings of securities.
4. Fully Paid Stock; Taxes. The Company agrees that the shares of the
-----------------------
Common Stock represented by each and every certificate of Warrant Shares on the
exercise of this Warrant shall be validly issued and outstanding, fully paid and
nonassessable, and not subject to preemptive rights or rights of first refusal,
and the Company will take all such actions as may be necessary to assure that
the par value or stated value, if any, per share of the Common Stock is at all
times equal to or less than the then Per Share Warrant Price. The Company
further covenants and agrees that it will pay, when due and payable, any and all
Federal and State stamp, original issue or similar taxes which may be payable in
respect of the issue of any Warrant Share or any certificate thereof.
5. Adjustments for Purchase Price and Number of Shares.
---------------------------------------------------
In the event that, prior to the issuance by the Company of all the Warrant
Shares issuable upon exercise of this Warrant, there shall be any change in the
outstanding common stock of the Company by reason of the declaration of stock
dividends, or through stock splits or combinations, the remaining Warrant Shares
still subject to this Warrant and the purchase price
6
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thereof (i.e. per Share Warrant Price) shall be appropriately adjusted (but
without regard to fractions) by the Board of Directors of the Company to reflect
such change.
6. Merger or Consolidation.
-----------------------
In case of any consolidation of the Company with, or merger of the Company
with, or merger of the Company into, another corporation (other than a
consolidation or merger which does not result in any reclassification or change
of the outstanding common stock of the Company), the corporation formed by such
consolidation or merger shall execute and deliver to the Holder a supplemental
warrant agreement providing that the Holder shall have the right thereafter
(until the expiration of such Warrant) to receive, upon exercise of his Warrant,
the kind and amount of shares of stock and other securities and property
receivable upon such consolidation or merger by a holder of the number of shares
of common stock of the Company for which his Warrant might have been exercised
immediately prior to such consolidation, merger, sale or transfer. Such
supplemental warrant agreement shall provide for adjustments which shall be
identical to the adjustments provided in Section 5. The above provisions of this
Section 6 shall similarly apply to successive consolidations or mergers.
7. Limited Transferability; Successors. This Warrant may not be sold,
------------------------------------
transferred, assigned or hypothecated by the Holder except in compliance with
the provisions of the Act and the applicable state securities "blue sky" laws.
The Company may treat the registered Holder of this Warrant as he or it appears
on the Company's books at any time as the Holder for all purposes. All warrants
issued upon the transfer or assignment of this Warrant will be dated the same
date as this Warrant, and all rights of the holder thereof shall be identical to
those of the Holder. All the covenants, agreements, representations and
warranties contained in this Warrant shall bind the parties hereto and their
respective heirs, executors, administrators, distributees, successors and
assigns.
8. Loss, Etc., of Warrant. Upon receipt of evidence satisfactory to the
----------------------
Company of the loss, theft, destruction or mutilation of this Warrant, and of
indemnity reasonably satisfactory to the Company, if lost, stolen or destroyed,
and upon surrender and cancellation of this Warrant, if mutilated, the Company
shall execute and deliver to the Holder a new Warrant of like date, tenor and
denomination.
9. Warrant Holder Not Shareholder. Except as otherwise provided herein,
------------------------------
this Warrant does not confer upon the Holder any right to vote or to consent to
or receive notice as a stockholder of the Company, as such, in respect of any
matters whatsoever, or any other rights or liabilities as a stockholder, prior
to the exercise hereof.
10. Communication. No notice or other communication under this Warrant
-------------
shall be effective unless, but any notice or other communication shall be
effective and shall be deemed to have been given if, the same is in writing and
is delivered personally, mailed by certified or registered first-class mail,
postage prepaid, or sent via overnight courier addressed to:
(a) The Company at 137 Newbury Street, 8th Floor, Boston, MA 02116 or
other address as the Company has designated in writing to the Holder, or
(b) the Holder at such address as the Holder designates in writing to
the Company.
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11. Headings. The headings of this Warrant have been inserted as a matter
--------
of convenience and shall not affect the construction hereof.
12. Applicable Law. This Warrant shall be governed by and construed in
--------------
accordance with the law of the State of Delaware without giving effect to the
principles of conflicts of law thereof.
IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its
President and attested by its Secretary on the date indicated below.
BOSTON LIFE SCIENCES, INC.
By: ______________________
David Hillson
President
Date: December 1, 1999
ATTEST:
_______________________
Joseph Hernon
Secretary
Date: December 1, 1999
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SUBSCRIPTION
------------
The undersigned, _______________________, pursuant to the provisions
of the foregoing Warrant, hereby agrees to Subscribe for and purchase
________________ shares of the Common Stock, par value $.01 per share, of Boston
Life Sciences, Inc. covered by said Warrant, and makes payment therefor in full
at the price per share provided by said Warrant.
Dated:__________________ Signature:_________________________
Address:___________________________
___________________________
ASSIGNMENT
----------
FOR VALUE RECEIVED______________ hereby sells, assigns and transfers
unto ______________________the foregoing Warrant and all right evidenced
thereby, and does irrevocably constitute and appoint
____________________________, attorney, to transfer said Warrant on the books of
Boston Life Sciences, Inc.
Dated:__________________ Signature:_________________________
Address:___________________________
___________________________
PARTIAL ASSIGNMENT
------------------
FOR VALUE RECEIVED __________________ hereby assigns and transfers
unto ________________________ the right to purchase ___________ shares of the
Common Stock, par value $.01 per share, of Boston Life Sciences, Inc. covered by
the foregoing Warrant, and a proportionate part of said Warrant and the rights
evidenced thereby, and does irrevocably constitute and appoint
____________________________, attorney, to transfer that part of said Warrant on
the books of Boston Life Sciences, Inc.
Dated:__________________ Signature:_________________________
Address:___________________________
___________________________
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