<PAGE>

                                                                  EXHIBIT 4.3(i)

NEITHER THIS WARRANT NOR THE SHARES ISSUABLE UPON EXERCISE HEREOF HAVE BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT")
OR ANY OTHER APPLICABLE STATE SECURITIES LAWS IN RELIANCE UPON AN EXEMPTION FROM
THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND SUCH OTHER SECURITIES
LAWS. NEITHER THIS WARRANT NOR THE SHARES ISSUABLE UPON EXERCISE HEREOF MAY BE
SOLD, PLEDGED, TRANSFERRED, ENCUMBERED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT
TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR IN A
TRANSACTION WHICH IS EXEMPT FROM REGISTRATION UNDER THE PROVISIONS OF THE
SECURITIES ACT OR ANY APPLICABLE STATE LAWS.

                             STOCK PURCHASE WARRANT

                 To Purchase 1,123,125 Shares of Common Stock of

                                RAZORFISH, INC.

             THIS CERTIFIES that, for value received, Ladenburg Thalmann & Co.
Inc. (the "Holder"), is entitled, upon the terms and subject to the limitations
on exercise and the conditions hereinafter set forth, at any time on or after
the date hereof (the "Initial Exercise Date") and on or prior to the close of
business on April 30, 2005 (the earlier of such date or such other date as this
Warrant shall expire pursuant to the terms hereof, the "Termination Date") but
not thereafter, to subscribe for and purchase from RAZORFISH, INC., a
corporation incorporated in the State of Delaware (the "Company"), up to
1,123,125 shares (the "Warrant Shares") of Common Stock, $0.01 par value, of the
Company (the "Common Stock"). The purchase price of one share of Common Stock
(the "Exercise Price") under this Warrant shall be $0.54. The Exercise Price and
the number of shares for which the Warrant is exercisable shall be subject to
adjustment as provided herein. In the event of any conflict between the terms of
this Warrant and the Common Stock and Warrants Purchase Agreement dated as of
April 18, 2002 pursuant to which this Warrant shall be deemed to have been
issued (the "Purchase Agreement"), the Purchase Agreement shall control.
Capitalized terms used and not otherwise defined herein shall have the meanings
set forth for such terms in the Purchase Agreement.

             1. Title to Warrant. Prior to the Termination Date and subject to
                ----------------
compliance with applicable laws and the terms hereof, this Warrant and all
rights hereunder are transferable, in whole or in part, at the office or agency
of the Company by the holder hereof in person or by duly authorized attorney,
upon surrender of this Warrant together with the Assignment Form annexed hereto
properly endorsed.

             2. Authorization of Shares. The Company covenants that all shares
                -----------------------
of Common Stock which may be issued upon the exercise of the purchase rights
represented by this Warrant will, upon exercise of the purchase rights
represented by this Warrant, be duly authorized, validly issued, fully paid and
nonassessable and free from all taxes, liens and charges


                                       1

<PAGE>

in respect of the issue thereof (other than taxes in respect of any transfer
occurring contemporaneously with such issue).

             3. Exercise of Warrant.
                -------------------

                (a) Except as provided in Section 4 herein, exercise of the
purchase rights represented by this Warrant may be made at any time or times on
or after the Initial Exercise Date, and before the close of business on the
Termination Date by the surrender of this Warrant and the Notice of Exercise
Form annexed hereto duly executed, at the office of the Company (or such other
office or agency of the Company as it may designate by notice in writing to the
registered holder hereof at the address of such holder appearing on the books of
the Company) and upon payment of the Exercise Price of the shares thereby
purchased by wire transfer or cashier's check drawn on a United States bank, the
holder of this Warrant shall be entitled to receive a certificate for the number
of shares of Common Stock so purchased. Certificates for shares purchased
hereunder shall be delivered to the holder hereof within three (3) Trading Days
after the date on which this Warrant shall have been exercised as aforesaid.
This Warrant shall be deemed to have been exercised and such certificate or
certificates shall be deemed to have been issued, and Holder or any other person
so designated to be named therein shall be deemed to have become a holder of
record of such shares for all purposes, as of the date the Warrant has been
exercised by payment to the Company of the Exercise Price and all taxes required
to be paid by Holder, if any, pursuant to Section 5 prior to the issuance of
such shares, have been paid.

                (b) If this Warrant shall have been exercised in part, the
Company shall, at the time of delivery of the certificate or certificates
representing Warrant Shares, deliver to Holder a new Warrant evidencing the
rights of Holder to purchase the unpurchased shares of Common Stock called for
by this Warrant, which new Warrant shall in all other respects be identical with
this Warrant.

                (c) If the Registration Statement is not effective at any time
when it is required to be effective pursuant to the Registration Rights
Agreement, then this Warrant shall also be exercisable by means of a "cashless
exercise" in which the holder shall be entitled to receive a certificate for the
number of shares equal to the quotient obtained by dividing [(A-B) (X)] by (A),
where:

(A) = the volume weighted average price per share of Common Stock on the Trading
Day preceding the date of such election on the Nasdaq Stock Market, or if the
Common Stock is not traded on the Nasdaq Stock Market, then the Principal Market
in terms of volume, and converted into US Dollars;

(B) =  the Exercise Price of the Warrants; and

(X) = the number of shares issuable upon exercise of the Warrants in accordance
with the terms of this Warrant.

             4. No Fractional Shares or Scrip. No fractional shares or scrip
                -----------------------------
representing fractional shares shall be issued upon the exercise of this
Warrant. As to any fraction of a share



                                       2

<PAGE>

which Holder would otherwise be entitled to purchase upon such exercise, the
Company shall pay a cash adjustment in respect of such final fraction in an
amount equal to such fraction multiplied by the Exercise Price.

             5. Charges, Taxes and Expenses. Issuance of certificates for shares
                ---------------------------
of Common Stock upon the exercise of this Warrant shall be made without charge
to the holder hereof for any issue or transfer tax or other incidental expense
in respect of the issuance of such certificate, all of which taxes and expenses
shall be paid by the Company, and such certificates shall be issued in the name
of the holder of this Warrant or in such name or names as may be directed by the
holder of this Warrant; provided, however, that in the event certificates for
shares of Common Stock are to be issued in a name other than the name of the
holder of this Warrant, this Warrant when surrendered for exercise shall be
accompanied by the Assignment Form attached hereto duly executed by the holder
hereof; and the Company may require, as a condition thereto, the payment of a
sum sufficient to reimburse it for any transfer tax incidental thereto.

             6. Closing of Books. The Company will not close its stockholder
                ----------------
books or records in any manner which prevents the timely exercise of this
Warrant.

             7. Transfer, Division and Combination. (a) Subject to compliance
                ----------------------------------
with any applicable securities laws, transfer of this Warrant and all rights
hereunder, in whole or in part, shall be registered on the books of the Company
to be maintained for such purpose, upon surrender of this Warrant at the
principal office of the Company, together with a written assignment of this
Warrant substantially in the form attached hereto duly executed by Holder or its
agent or attorney and funds sufficient to pay any transfer taxes payable upon
the making of such transfer. Upon such surrender and, if required, such payment,
the Company shall execute and deliver a new Warrant or Warrants in the name of
the assignee or assignees and in the denomination or denominations specified in
such instrument of assignment, and shall issue to the assignor a new Warrant
evidencing the portion of this Warrant not so assigned, and this Warrant shall
promptly be cancelled. A Warrant, if properly assigned, may be exercised by a
new holder for the purchase of shares of Common Stock without having a new
Warrant issued.

                (b) This Warrant may be divided or combined with other Warrants
upon presentation hereof at the aforesaid office of the Company, together with a
written notice specifying the names and denominations in which new Warrants are
to be issued, signed by Holder or its agent or attorney. Subject to compliance
with Section 7(a), as to any transfer which may be involved in such division or
combination, the Company shall execute and deliver a new Warrant or Warrants in
exchange for the Warrant or Warrants to be divided or combined in accordance
with such notice.

                (c) The Company shall prepare, issue and deliver at its own
expense (other than transfer taxes) the new Warrant or Warrants under this
Section 7.

                (d) The Company agrees to maintain, at its aforesaid office,
books for the registration and the registration of transfer of the Warrants.

             8. No Rights as Shareholder until Exercise. This Warrant does not
                ---------------------------------------
entitle the holder hereof to any voting rights or other rights as a shareholder
of the Company prior to the



                                       3

<PAGE>

exercise hereof. Upon the surrender of this Warrant and the payment of the
aggregate Exercise Price, the Warrant Shares so purchased shall be deemed to be
issued to such holder as the record owner of such shares as of the close of
business on the later of the date of such surrender or payment.

             9. Loss, Theft, Destruction or Mutilation of Warrant. The Company
                -------------------------------------------------
covenants that upon receipt by the Company of evidence reasonably satisfactory
to it of the loss, theft, destruction or mutilation of this Warrant certificate
or any stock certificate relating to the Warrant Shares, and in case of loss,
theft or destruction, of indemnity or security reasonably satisfactory to it
(which shall not include the posting of any bond), and upon surrender and
cancellation of such Warrant or stock certificate, if mutilated, the Company
will make and deliver a new Warrant or stock certificate of like tenor and dated
as of such cancellation, in lieu of such Warrant or stock certificate.

             10. Saturdays, Sundays, Holidays, etc. If the last or appointed day
                 ---------------------------------
for the taking of any action or the expiration of any right required or granted
herein shall be a Saturday, Sunday or a legal holiday, then such action may be
taken or such right may be exercised on the next succeeding day not a Saturday,
Sunday or legal holiday.

             11. Adjustments of Exercise Price and Number of Warrant Shares;
                 -----------------------------------------------------------
Stock Splits, etc. The number and kind of securities purchasable upon the
-----------------
exercise of this Warrant and the Exercise Price shall be subject to adjustment
from time to time upon the happening of any of the following. In case the
Company shall (i) pay a dividend in shares of Common Stock or make a
distribution in shares of Common Stock to holders of its outstanding Common
Stock, (ii) subdivide its outstanding shares of Common Stock into a greater
number of shares of Common Stock, (iii) combine its outstanding shares of Common
Stock into a smaller number of shares of Common Stock or (iv) issue any shares
of its capital stock in a reclassification of the Common Stock (including,
without limitation, any spin-off of any subsidiary), then the number of Warrant
Shares purchasable upon exercise of this Warrant immediately prior thereto shall
be adjusted accordingly. Upon each such adjustment of the kind and number of
Warrant Shares or other securities of the Company which are purchasable
hereunder, the holder of this Warrant shall thereafter be entitled to purchase
the number of Warrant Shares or other securities resulting from such adjustment
at an Exercise Price per Warrant Share or other security obtained by multiplying
the Exercise Price in effect immediately prior to such adjustment by the number
of Warrant Shares purchasable pursuant hereto immediately prior to such
adjustment and dividing by the number of Warrant Shares or other securities of
the Company resulting from such adjustment. An adjustment made pursuant to this
paragraph shall become effective immediately after the effective date of such
event retroactive to the record date, if any, for such event.

             12. Reorganization, Reclassification, Merger, Consolidation or
                 ----------------------------------------------------------
Disposition of Assets. In case the Company shall reorganize its capital,
---------------------
reclassify its capital stock, consolidate or merge with or into another
corporation (where the Company is not the surviving corporation or where there
is a change in or distribution with respect to the Common Stock of the Company),
or sell, transfer or otherwise dispose of all or substantially all its property,
assets or business to another corporation and, pursuant to the terms of such
reorganization, reclassification, merger, consolidation or disposition of
assets, shares of common stock of the successor or acquiring corporation, or any
cash, shares of stock or other securities or property of any nature whatsoever


                                       4

<PAGE>

(including warrants or other subscription or purchase rights) in addition to
or in lieu of common stock of the successor or acquiring corporation ("Other
Property"), are to be received by or distributed to the holders of Common Stock
of the Company, then Holder shall have the right thereafter to receive, upon
exercise of this Warrant, the number of shares of common stock of the successor
or acquiring corporation or of the Company, if it is the surviving corporation,
and Other Property receivable upon or as a result of such reorganization,
reclassification, merger, consolidation or disposition of assets by a holder of
the number of shares of Common Stock for which this Warrant is exercisable
immediately prior to such event. For the avoidance of doubt, in the event of any
transaction referred to in the previous sentence in which the Company is not the
surviving company, the Holder shall be required to exercise this Warrant in
order to receive the consideration to be received by or distributed to the
holders of the Common Stock of the Company and if the Holder fails to so
exercise this Warrant within one week of the closing of such transaction, this
Warrant shall terminate. The foregoing provisions of this Section 12 shall
similarly apply to successive reorganizations, reclassifications, mergers,
consolidations or disposition of assets.

             13. Voluntary Adjustment by the Company. The Company may at any
                 -----------------------------------
time during the term of this Warrant reduce the then current Exercise Price to
any amount and for any period of time deemed appropriate by the Board of
Directors of the Company.

             14. Notice of Adjustment. Whenever the number of Warrant Shares or
                 --------------------
number or kind of securities or other property purchasable upon the exercise of
this Warrant or the Exercise Price is adjusted, as herein provided, the Company
shall promptly mail by registered or certified mail, return receipt requested,
to the holder of this Warrant notice of such adjustment or adjustments setting
forth the number of Warrant Shares (and other securities or property)
purchasable upon the exercise of this Warrant and the Exercise Price of such
Warrant Shares (and other securities or property) after such adjustment, setting
forth a brief statement of the facts requiring such adjustment and setting forth
the computation by which such adjustment was made. Such notice, in the absence
of manifest error, shall be conclusive evidence of the correctness of such
adjustment.

             15. Notice of Corporate Action. If at any time:
                 --------------------------

                 (a) the Company shall take a record of the holders of its
Common Stock for the purpose of entitling them to receive a dividend or other
distribution, or any right to subscribe for or purchase any evidences of its
indebtedness, any shares of stock of any class or any other securities or
property, or to receive any other right, or

                 (b) there shall be any capital reorganization of the Company,
any reclassification or recapitalization of the capital stock of the Company or
any consolidation or merger of the Company with, or any sale, transfer or other
disposition of all or substantially all the property, assets or business of the
Company to, another corporation or,

                 (c) there shall be a voluntary or involuntary dissolution,
liquidation or winding up of the Company;



                                        5

<PAGE>

then, in any one or more of such cases, the Company shall give to Holder (i) at
least 20 days' (or as many days as is reasonably practicable) prior written
notice of the date on which a record date shall be selected for such dividend,
distribution or right or for determining rights to vote in respect of any such
reorganization, reclassification, merger, consolidation, sale, transfer,
disposition, liquidation or winding up, and (ii) in the case of any such
reorganization, reclassification, merger, consolidation, sale, transfer,
disposition, dissolution, liquidation or winding up, at least 20 days' prior
written notice of the date when the same shall take place. Such notice in
accordance with the foregoing clause also shall specify (i) the date on which
any such record is to be taken for the purpose of such dividend, distribution or
right, the date on which the holders of Common Stock shall be entitled to any
such dividend, distribution or right, and the amount and character thereof, and
(ii) the date on which any such reorganization, reclassification, merger,
consolidation, sale, transfer, disposition, dissolution, liquidation or winding
up is to take place and the time, if any such time is to be fixed, as of which
the holders of Common Stock shall be entitled to exchange their shares of Common
Stock for securities or other property deliverable upon such disposition,
dissolution, liquidation or winding up. Each such written notice shall be
sufficiently given if addressed to Holder at the last address of Holder
appearing on the books of the Company and delivered in accordance with Section
17(c).

             16. Authorized Shares. The Company covenants that during the period
                 -----------------
the Warrant is outstanding, it will reserve from its authorized and unissued
Common Stock a sufficient number of shares to provide for the issuance of the
Warrant Shares upon the exercise of any purchase rights under this Warrant. The
Company further covenants that its issuance of this Warrant shall constitute
full authority to its officers who are charged with the duty of executing stock
certificates to execute and issue the necessary certificates for the Warrant
Shares upon the exercise of the purchase rights under this Warrant. The Company
will take all such reasonable action as may be necessary to assure that such
Warrant Shares may be issued as provided herein without violation of any
applicable law or regulation, or of any requirements of the Principal Market
upon which the Common Stock may be listed.

             The Company shall not by any action, including, without limitation,
amending its articles of incorporation or through any reorganization, transfer
of assets, consolidation, merger, dissolution, issue or sale of securities or
any other voluntary action, avoid or seek to avoid the observance or performance
of any of the terms of this Warrant, but will at all times in good faith assist
in the carrying out of all such terms and in the taking of all such actions as
may be necessary or appropriate to protect the rights of Holder against
impairment. Without limiting the generality of the foregoing, the Company will
(a) not increase the par value of any shares of Common Stock receivable upon the
exercise of this Warrant above the amount payable therefor upon such exercise
immediately prior to such increase in par value, (b) take all such action as may
be necessary or appropriate in order that the Company may validly and legally
issue fully paid and nonassessable shares of Common Stock upon the exercise of
this Warrant, and (c) use commercially reasonable efforts to obtain all such
authorizations, exemptions or consents from any public regulatory body having
jurisdiction thereof as may be necessary to enable the Company to perform its
obligations under this Warrant.

             Before taking any action which would result in an adjustment in the
number of shares of Common Stock for which this Warrant is exercisable or in the
Exercise Price, the Company shall obtain all such authorizations or exemptions
thereof, or consents


                                       6

<PAGE>

thereto, as may be necessary from any public regulatory body or bodies having
jurisdiction thereof.

             17. Miscellaneous.
                 -------------

                 (a) Jurisdiction. This Warrant shall be binding upon any
successors or assigns of the Company. This Warrant shall constitute a contract
under the laws of New York, without regard to its conflict of law, principles or
rules that would result in the application of the laws of any other
jurisdiction, and be subject to arbitration pursuant to the terms set forth in
the Purchase Agreement.

                 (b) Restrictions. The holder hereof acknowledges that the
Warrant Shares acquired upon the exercise of this Warrant, if not registered,
will have restrictions upon resale imposed by state and federal securities laws.

                 (c) Notices. Any notice, request or other document required or
permitted to be given or delivered to the holder hereof by the Company shall be
delivered in accordance with the notice provisions of the Purchase Agreement.

                 (d) Remedies. Holder, in addition to being entitled to exercise
all rights granted by law, including recovery of damages, will be entitled to
specific performance of its rights under this Warrant. The Company agrees that
monetary damages would not be adequate compensation for any loss incurred by
reason of a breach by it of the provisions of this Warrant and hereby agrees to
waive the defense in any action for specific performance that a remedy at law
would be adequate.

                 (e) Successors and Assigns. Subject to applicable securities
laws and the terms of the Purchase Agreement, this Warrant and the rights and
obligations evidenced hereby shall inure to the benefit of and be binding upon
the successors of the Company and the successors and permitted assigns of
Holder. The provisions of this Warrant are intended to be for the benefit of all
Holders from time to time of this Warrant and shall be enforceable by any such
Holder or holder of Warrant Shares.

                 (f) Amendment. This Warrant may be modified or amended or the
provisions hereof waived with the written consent of the Company --------- and
the Holder.

                 (g) Severability. Wherever possible, each provision of this
Warrant shall be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Warrant shall be prohibited by or
invalid under applicable law, such provision shall be ineffective to the extent
of such prohibition or invalidity, without invalidating the remainder of such
provisions or the remaining provisions of this Warrant.

                 (h) Headings. The headings used in this Warrant are for the
                     --------
convenience of reference only and shall not, for any purpose, be deemed a part
of this Warrant.

                 (i) Integration. This Warrant, and the Purchase Agreement and
                     -----------
the Registration Rights Agreement pursuant to which this Warrant was issued, set
forth the entire agreement and understanding of the parties relating to the
subject matter hereof and supersede all


                                        7

<PAGE>

prior and contemporaneous agreements, negotiations and understandings between
the parties, both oral and written relating to the subject matter hereof.



                                       8

<PAGE>

             IN WITNESS WHEREOF, the Company has caused this Warrant to be
executed by its officer thereunto duly authorized.

Dated: ________ __, 2002
                                  RAZORFISH, INC.


                                  By:
                                         ------------------------------------

                                  Name:
                                         ------------------------------------

                                  Title:
                                         ------------------------------------


                                       9

<PAGE>


                               NOTICE OF EXERCISE



To:      [________________________]


             (1)______The undersigned hereby elects to purchase ________ shares
of Common Stock (the "Common Stock"), of [______________________] pursuant to
the terms of the attached Warrant, and tenders herewith payment of the exercise
price in full, together with all applicable transfer taxes, if any.

             (2)______Please issue a certificate or certificates representing
said shares of Common Stock in the name of the undersigned or in such other name
as is specified below:

                      -------------------------------
                      (Name)

                      -------------------------------
                      (Address)

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




Dated:


                                            ------------------------------
                                            Signature



<PAGE>

                                 ASSIGNMENT FORM

                    (To assign the foregoing warrant, execute
                   this form and supply required information.
                 Do not use this form to exercise the warrant.)

             FOR VALUE RECEIVED, the foregoing Warrant and all rights evidenced
thereby are hereby assigned to


                                                whose address is
------------------------------------------------


---------------------------------------------------------------.

                                       Dated:  ______________, _______


                           Holder's Signature:
                                               -----------------------------

                           Holder's Address:
                                               -----------------------------

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



Signature Guaranteed:  ___________________________________________




NOTE: The signature to this Assignment Form must correspond with the name as it
appears on the face of the Warrant, without alteration or enlargement or any
change whatsoever, and must be guaranteed by a bank or trust company. Officers
of corporations and those acting in an fiduciary or other representative
capacity should file proper evidence of authority to assign the foregoing
Warrant.