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                                                                EXHIBIT 10.16

NEITHER THESE WARRANTS NOR THE SHARES UNDERLYING THESE WARRANTS HAVE BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933 OR THE LAWS OF ANY STATE. THEY MAY
NOT BE SOLD OR OTHERWISE TRANSFERRED UNLESS THEY ARE REGISTERED UNDER SUCH ACT
AND APPLICABLE STATE SECURITIES LAWS OR THE COMPANY HAS RECEIVED THE OPINION OF
COUNSEL REASONABLY SATISFACTORY TO IT TO THE EFFECT THAT AN EXEMPTION FROM
REGISTRATION IS AVAILABLE.

15,384 Warrants                                                December 18, 1997

                                 INTRALINKS INC.

                               WARRANT CERTIFICATE

            This warrant certificate ("Warrant Certificate") certifies that for
value received, Landwell Financial Services, Inc. or its assigns or designees
(the "Holder") is the owner of the number of warrants ("Warrants") specified
above, each of which entitles the Holder thereof to purchase, at the time
specified herein but in any event no later than the close of business on or
before December 18, 2005 (the "Final Expiration Date") one fully paid and
non-assessable share of Common Stock, $.01 par value ("Common Stock"), of
IntraLinks Inc., a Delaware corporation (the "Company"), at the Exercise Price
(as hereinafter defined) per share of Common Stock in lawful money of the United
States of America in cash or by certified or cashier's check or a combination of
cash and certified or cashier's check (subject to adjustment as hereinafter
provided).

      1.    Warrant; Exercise Event

            Each Warrant shall entitle the Holder to purchase one Warrant Share
(as hereinafter defined) of the Company upon the occurrence of an Exercise
Event. An "Exercise Event" is herein defined as the earlier to occur of (i) the
consummation by the Company of an equity financing in which the Company receives
gross proceeds of at least $3,000,000 (the "Subsequent Financing"); (ii) the
Company's initial public offering of its securities ("IPO"); or (iii) a Change
in Control of the Company. A "Change in Control" means an event or series of
events as a result of which (i) any "person" or "group" (as such terms are used
in Sections 13(d) or 14(d) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act")) who is not currently a shareholder of the Company acquires
"beneficial ownership" (as determined in accordance with Rule 13d-3 under the
Exchange Act), directly or indirectly, of more than 50% of the total voting
power of the outstanding Voting Stock (as defined below) of the Company;
provided, however, that any such person or group shall not be deemed to be the
beneficial owner of, or to beneficially own, any Voting Stock tendered in a
tender or exchange offer until such Voting Stock is accepted for purchase or
exchange under such tender or exchange offer. For purposes hereof,
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Voting Stock means stock of any class or classes (or equivalent interests) if
the holders of the stock of such class or classes (or equivalent interests) are
ordinarily, in the absence of contingencies, entitled to vote for the election
of a majority of the directors (or Persons (as defined herein) performing
similar functions) of the corporation, association or other such business entity
involved, even though the right so to vote has been suspended by the happening
of a contingency. Persons means any individual, corporation, partnership, trust,
unincorporated association, business, or other legal entity, and any government
or any governmental agency or political subdivision thereof. The shares of
Common Stock issuable upon exercise of the Warrants (and/or other shares of
Common Stock so issuable by reason of any adjustments pursuant to Section 7) are
sometimes referred to herein as the "Warrant Shares."

      2.    Exercise Price

            The exercise price payable upon exercise of the Warrants (the
"Exercise Price") shall be (i) if exercised upon consummation of the Subsequent
Financing, equal to a ten percent (10%) discount to the purchase price per share
of the Company's Common Stock, or equivalent share, purchased in the Subsequent
Financing; (ii) if exercised upon the IPO, equal to a ten percent (10%) discount
to the purchase price per share of the shares of the Company's Common Stock, or
equivalent shares, sold in the IPO; and (iii) if exercised upon a Change in
Control, equal to $6.50 per share, as adjusted pursuant to Section 7 hereof.

      3.    Manner of Exercise; Expiration

            The Company shall provide the Holder with Notice of an Exercise
Event at least ten (10) days before the occurrence of the Exercise Event
("Exercise Event Notice"). The Warrants will be exercisable, at the option of
the Holder, in whole or in part at any time from the time the Holder receives
the Exercise Event Notice until 12:00 p.m. on the day of the Exercise Event
("Expiration Time") and upon surrender of this Warrant Certificate to the
Company, together with a duly completed Notice of Exercise in the form attached
hereto as Exhibit A, and payment of an amount equal to the Exercise Price times
the number of Warrants to be exercised. These Warrants will expire at the
Expiration Time. In the case of exercise of less than all the Warrants
represented by this Warrant Certificate, the Holder shall forfeit the balance of
such Warrants. If an Exercise Event does not occur on or prior to the Final
Expiration Date, this Warrant shall expire on the Final Expiration Date and the
Holder shall have no rights hereunder.


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      4.    Registration and Transfer on Company Books

            4.1 The Company shall maintain books for the registration and
transfer of the Warrants and the registration and transfer of the Warrant
Shares.

            4.2 Prior to due presentment for registration of transfer of this
Warrant Certificate or the Warrant Shares, the Company may deem and treat the
registered Holder as the absolute owner thereof.

            4.3 The Company shall register upon its books any transfer of a
Warrant Certificate upon surrender of same to the Company with a written
instrument of transfer duly executed by the registered Holder or by a duly
authorized attorney. Upon any such registration of transfer, new Warrant
Certificate(s) shall be issued to the transferee(s) and the surrendered Warrant
Certificate shall be canceled by the Company. A Warrant Certificate may also be
exchanged, at the option of the Holder, for new Warrant Certificates of
different denominations representing in the aggregate the number of Warrants
evidenced by the Warrant Certificate surrendered.

      5.    Reservation of Shares

            The Company covenants that it will at all times reserve and keep
available out of its authorized capital stock, solely for the purpose of issue
upon exercise of the Warrants, such number of shares of Common Stock as shall
then be issuable upon the exercise of all outstanding Warrants. The Company
covenants that all Warrant Shares shall be duly and validly issued and fully
paid and non-assessable and free from all taxes, liens and charges with respect
to the issue thereof and that upon issuance, such Warrant Shares shall be listed
on each national securities exchange, if any, on which the other shares of such
outstanding capital stock of the Company are then listed.

      6.    Loss or Mutilation

            Upon receipt by the Company of reasonable evidence of the ownership
of and the loss, theft, destruction or mutilation of any Warrant Certificate
and, in the case of loss, theft or destruction, an indemnity reasonably
satisfactory to the Company, or, in the case of mutilation, upon surrender and
cancellation of the mutilated Warrant Certificate, the Company shall execute and
deliver in lieu thereof a new Warrant Certificate representing an equal number
of Warrants.


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      7.    Adjustment of Exercise Price and Number of Shares Deliverable

            7.1 The number of Warrant Shares purchasable upon the exercise of
each Warrant and the Exercise Price with respect to the Warrant Shares shall be
subject to adjustment as follows:

                  (a) In case the Company shall (i) declare a dividend or make a
      distribution on its Common Stock payable in shares of its capital stock,
      (ii) subdivide its outstanding shares of Common Stock through stock split
      or otherwise, (iii) combine its outstanding shares of Common Stock into a
      smaller number of shares of Common Stock, or (iv) issue by
      reclassification of its Common Stock (including any such reclassification
      in connection with a consolidation or merger in which the Company is the
      continuing corporation) other securities of the Company, the number and/or
      nature of Warrant Shares purchasable upon exercise of each Warrant
      immediately prior thereto shall be adjusted so that the Holder shall be
      entitled to receive the kind and number of Warrant Shares or other
      securities of the Company which he would have owned or have been entitled
      to receive after the happening of any of the events described above had
      such Warrant been exercised immediately prior to the happening of such
      event or any record date with respect thereto. An adjustment made pursuant
      to this Paragraph (a) shall become effective retroactively as of the
      record date of such event.

                  (b) In the event of any capital reorganization or any
      reclassification of the capital stock of the Company or in case of the
      consolidation or merger of the Company with another corporation (other
      than a consolidation or merger in which the outstanding shares of the
      Company's Common Stock are not converted into or exchanged for other
      rights or interests), or in the case of any sale, transfer or other
      disposition to another corporation of all or substantially all the
      properties and assets of the Company, the Holder of each Warrant shall
      thereafter be entitled to purchase (and it shall be a condition to the
      consummation of any such reorganization, reclassification, consolidation,
      merger, sale, transfer or other disposition that appropriate provisions
      shall be made so that such Holder shall thereafter be entitled to
      purchase) the kind and amount of shares of stock and other securities and
      property (including cash) which the Holder would have been entitled to
      receive had such Warrants been exercised immediately prior to the
      effective date of such reorganization, reclassification, consolidation,
      merger, sale, transfer or other disposition; and in any such case,
      appropriate adjustments shall be made in the application of the provisions
      of this Section 7 with respect to rights and interest thereafter of the
      Holder of the Warrants so that the provisions of this Section 7 shall
      thereafter be applicable,


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      as near as reasonably may be, in relation to any shares or other property
      thereafter purchasable upon the exercise of the Warrants. The provisions
      of this Section 7.1(b) shall similarly apply to successive
      reorganizations, reclassifications, consolidations, mergers, sales,
      transfers or other dispositions.

                  (c) Whenever the number of Warrant Shares purchasable upon the
      exercise of each Warrant is adjusted, as provided in this Section 7.1, the
      Exercise Price with respect to the Warrant Shares shall be adjusted by
      multiplying such Exercise Price immediately prior to such adjustment by a
      fraction, of which the numerator shall be the number of Warrant Shares
      purchasable upon the exercise of each Warrant immediately prior to such
      adjustment, and of which the denominator shall be the number of Warrant
      Shares so purchasable immediately thereafter.

            7.2 No adjustment in the number of Warrant Shares purchasable under
the Warrants, or in the Exercise Price with respect to the Warrant Shares, shall
be required unless such adjustment would require an increase or decrease of at
least 1% in the number of Warrant Shares issuable upon the exercise of such
Warrant, or in the Exercise Price thereof; provided, however, that any
adjustments which by reason of this Section 7.2 are not required to be made
shall be carried forward and taken into account in any subsequent adjustment.

            7.3 Whenever the number of Warrant Shares purchasable upon the
exercise of each Warrant or the Exercise Price of such Warrant Shares is
adjusted, as herein provided, the Company shall mail to the Holder, at the
address of the Holder shown on the books of the Company, a notice of such
adjustment or adjustments, prepared and signed by an officer of the Company,
which sets forth the number of Warrant Shares purchasable upon the exercise of
each Warrant and the Exercise Price of such Warrant Shares after such
adjustment, and a brief, statement of the facts requiring such adjustment.

            7.4 The form of Warrant Certificate need not be changed because of
any change in the Exercise Price, the number of Warrant Shares issuable upon the
exercise of a Warrant or the number of Warrants outstanding pursuant to this
Section 7, and Warrant Certificates issued before or after such change may state
the same Exercise Price, the same number of Warrants and the same number of
Warrant Shares issuable upon exercise of Warrants as are stated in the Warrant
Certificates theretofore issued pursuant to this Agreement. The Company may,
however, at any time, in its sole discretion, make any change in the form of
Warrant Certificate that it may deem appropriate and that does not affect the
substance thereof, and any Warrant Certificates thereafter issued or
countersigned, whether in exchange or substitution for an


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outstanding Warrant Certificate or otherwise, may be in the form as so changed.

      8.    Voluntary Adjustment by the Company

            The Company may, at its option, at any time during the term of the
Warrants, extend the date of the expiration of the Warrants.

      9.    Fractional Shares and Warrants; Determination of Market Price Per
            Share

            9.1 Anything contained herein to the contrary notwithstanding, the
Company shall not be required to issue any fraction of a share of Common Stock
in connection with the exercise of Warrants. Warrants may not be exercised in
such number as would result (except for the provisions of this paragraph) in the
issuance of a fraction of a share of Common Stock unless the Holder is
exercising all Warrants then owned by the Holder. In such event, the Company
shall, upon the exercise of all of such Warrants, issue to the Holder the
largest aggregate whole number of shares of Common Stock called for thereby upon
receipt of the Exercise Price for all of such Warrants and pay a sum in cash
equal to the remaining fraction of a share of Common Stock, multiplied by its
Market Price Per Share (as determined pursuant to Section 9.2 below) as of the
last business day preceding the date on which the Warrants are presented for
exercise.

            9.2 As used herein, the "Market Price Per Share" with respect to any
class or series of Common Stock on any date shall mean the closing price per
share of such class or series of Common Stock for the trading day immediately
preceding such date. The closing price for each such day shall be the last sale
price regular way or, in case no such sale takes place on such day, the average
of the closing bid and asked prices regular way, in either case on the principal
securities exchange on which the shares of such Common Stock of the Company are
listed or admitted to trading, the last sale price, or in case no sale takes
place on such day, the average of the closing bid and asked prices of such
Common Stock on NASDAQ or any comparable system, or if such Common Stock is not
reported on NASDAQ or a comparable system, the average of the closing bid and
asked prices as furnished by two members of the National Association of
Securities Dealers, Inc. selected from time to time by the Company for that
purpose. If such bid and asked prices are not available, then "Market Price Per
Share" shall be equal to the fair market value of such Common Stock as
determined in good faith by the Board of Directors of the Company.


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      10.   Issue Tax

            The issuance of certificates for shares of Common Stock upon
exercise of the Warrants shall be made without charge to the holders of such
Warrants for any issuance tax in respect thereof provided that the Company shall
not be required to pay any tax which may be payable in respect of any transfer
involved in the issuance and delivery of any certificate in a name other than
that of any holder of the Warrants.

      11.   Registration Rights

            The rights of the holder hereof with respect to the registration
under the Securities Act of 1933, as amended, of the Warrant Shares are set
forth in the Registration Rights Agreement, of even date herewith by and among
the Company and the several parties to such agreement.

      12.   Governing Law

            This Warrant Certificate shall be governed by and construed in
accordance with the laws of the State of Delaware.

            IN WITNESS WHEREOF, the Company has caused this Warrant Certificate
to be duly executed by its officers thereunto duly authorized and its corporate
seal to be affixed hereon, as of this 18th day of December, 1997.


[SEAL]                                     INTRALINKS INC.


                                           By:
                                               ---------------------------
                                               Name:
                                               Title:


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                                                                       EXHIBIT A

                               NOTICE OF EXERCISE

            The undersigned hereby irrevocably elects to exercise, pursuant to
Section 3 of the Warrant Certificate accompanying this Notice of Exercise,
_______ Warrants of the total number of Warrants owned by the undersigned
pursuant to the accompanying Warrant Certificate, and herewith makes payment of
the Exercise Price of such shares in full.


                                     ---------------------------------------
                                     Name of Holder


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

                                     Address:

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

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

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


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