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                                                                   Exhibit 10.13


                             SECURED PROMISSORY NOTE

$1,000,000                                                         April 5, 2000


     FOR VALUE RECEIVED, the undersigned, MARK CULHANE ("Borrower"), hereby
promises to pay to iManage, Inc., a Delaware corporation ("Lender"), or order,
the principal sum of One Million Dollars ($1,000,000), and accrued interest
thereon, as provided herein.

A.   Payments.

     1.   Interest. Interest shall accrue with respect to the outstanding
principal indebtedness under this Secured Promissory Note (this "Note") at the
per annum rate of 5.00%. Interest payable under this Note shall be calculated on
the basis of a three hundred sixty (360) day year for actual days elapsed.

     2.   Maturity Date.

          (a)  Except as set forth in Sections 2(b) and 2(c) below, the
principal amount and all accrued and unpaid interest due under this Note
(collectively, the "Borrower's Obligations") shall be due and payable in full
without any further notice or demand on the earlier of the following dates (the
"Maturity Date") (i) December 31, 2008; or (ii) three (3) trading days after the
first date upon which Borrower has the ability to sell the Pledged Collateral
(as defined in Paragraph A.6 below), subject to the Lender's trading window and
insider trading policy, as applicable, at a price equal to or greater than
Twenty Dollars ($20.00) per share.

          (b)  If there is a Constructive Termination (defined below) within two
(2) years following a Transfer in Control occurring before the Maturity Date,
then the Borrower's Obligations, as adjusted under Section 2(c) below, shall
become immediately due and payable on the first day after the fifth (5th)
trading day after the expiration of the period fixed by Lender's Amended 1997
Stock Option Plan as then in effect for Borrower's exercise of the Options (as
defined in the Pledge Agreement) on which borrower has the ability to sell the
Pledged Collateral subject to any restrictions due to trading windows, insider
trading policies, lock-ups or applicable law.

          (c)  If the events described in Section 2(b) occur and if the Net Cash
Realizable is less than the Borrower's Obligations, then only the amount of the
Borrower's Obligations equal to the Net Cash Realizable shall be due and payable
under Section 2(b) and the remaining amount of the Borrower's Obligations shall
be forgiven. For purposes of this Note, "Net Cash Realizable" shall mean the net
proceeds realizable from the sale of the Pledged Collateral less Applicable
Taxes, and "Applicable Taxes" shall mean (i) any and all taxes incurred by
Borrower as a result of the sale of the Pledged Collateral (or that would have
been incurred by the Borrower if the Pledged Collateral had been sold) and (ii)
any excise tax described in Section 4999 of the Internal Revenue Code of 1986,
as amended, incurred by Borrower (or that would have been incurred by the
Borrower if the Pledged Collateral had been sold) relating to acceleration and
vesting of stock options by reason of the Constructive Termination if any or all
benefits provided to Borrower on a Transfer of Control cause Borrower to be
subject to the excise tax.

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     3.   Application of Payments. Any payment received from Borrower shall be
first applied to accrued but unpaid interest and then to the principal amount
then outstanding under this Note.

     4.   Optional and Mandatory Prepayment.

          (a)  Borrower shall have the right at any time and from time to time
to prepay, in whole or in part, the principal amount of this Note, without
payment of any premium or penalty. Any principal prepayment must be accompanied
by a payment of all interest accrued but unpaid through the date of such
prepayment.

          (b)  Borrower shall pay over to Lender any cash or non-cash proceeds
realized on the sale or other disposition of any of the Pledged Collateral, net
of Applicable Taxes, with all such proceeds to be applied as a mandatory
prepayment of Borrower's obligations under this Note no later than three (3)
trading days after such sale or other disposition.

     5.   Form of Payment. The Borrower's Obligations are to be paid in lawful
money of the United States of America in immediately available funds.

     6.   Security. Pursuant to that certain Stock Pledge Agreement (the "Pledge
Agreement") of even date herewith, Borrower has granted Lender a security
interest in the Pledged Collateral (as defined therein) to secure the payment of
all of the Borrower's Obligations. Notwithstanding the foregoing, Borrower
acknowledges and agrees that this Note is a full recourse note and that Borrower
is liable for full payment of the Borrower's Obligations without regard to the
value at any time or from time to time of the Pledged Collateral.

B.   Events of Default.

     1.   The occurrence of any one or more of the following events shall
constitute an "Event of Default" under this Note:

          (a)  Borrower's breach of the obligation to pay any amount payable
under this Note on the date that it is due and payable;

          (b)  The occurrence of an Event of Default under the Pledge Agreement;
or

          (c)  Borrower's institution of proceedings against it, or Borrower's
filing of a petition or answer or consent seeking reorganization or release,
under the federal Bankruptcy Code, or any other applicable federal or state law
relating to Lender's rights and remedies, or Borrower's consent to the filing of
any such petition or the appointment of a receiver, liquidator, assignee,
trustee or other similar official of Borrower or of any substantial part of
Borrower's property, or Borrower's making of an assignment for the benefit of
creditors.

     2.   Rights and Remedies on Event of Default. On the occurrence of an Event
of Default, all principal, interest and charges owing under this Note shall
immediately and without the requirement of further notice or other action by
Lender become due and payable and Lender

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shall have the right to enforce this Note by exercise of the rights and remedies
granted to it by applicable law and to such remedies as are specified in the
Pledge Agreement.

C.   Other Provisions.

     1.   Definitions.

          (a)  For the purposes hereof, a "Transfer of Control" shall mean an
Ownership Change Event (defined below) or a series of related Ownership Change
Events (collectively, the "Transaction") wherein the stockholders of the Lender
immediately before the Transaction do not retain immediately after the
Transaction, in substantially the same proportions as their ownership of shares
of the Lender's voting stock immediately before the Transaction, direct or
indirect beneficial ownership of more than fifty percent (50%) of the total
combined voting power of the outstanding voting stock of the Lender or the
corporation or corporations to which the assets of the Lender were transferred
(the "Transferee Corporation(s)"), as the case may be. For purposes of the
preceding sentence, indirect beneficial ownership shall include, without
limitation, an interest resulting from ownership of the voting stock of one or
more corporations which, as a result of the Transaction, own the Lender or the
Transferee Corporation(s), as the case may be, either directly or through one or
more subsidiary corporations. The board of directors of the Lender shall have
the right to determine whether multiple sales or exchanges of the voting stock
of the Lender or multiple Ownership Change Events are related, and its
determination shall be final, binding and conclusive.

          (b)  For the purposes hereof, an "Ownership Change Event" shall be
deemed to have occurred if any of the following occurs with respect to the
Lender:

               (i)  the direct or indirect sale or exchange in a single or
series of related transactions by the stockholders of the Lender of more than
fifty percent (50%) of the voting stock of the Lender;

               (ii) a merger or consolidation in which the Lender is a party;

               (iii) the sale, exchange, or transfer of all or substantially all
of the assets of the Lender; of a liquidation or dissolution of the Lender.

          (c)  For the purposes hereof, "Constructive Termination" means a
termination of Borrower's employment by the Lender (or any successor entity)
other than for Cause, or Borrower's resignation from Lender (or any successor
entity) within thirty (30) days following an event deemed to be Good Reason.

          (d)  For the purposes hereof, "Cause" means (A) willful misconduct or
gross negligence in performance of Borrower's duties as Chief Financial Officer
of Lender (or any successor entity), including his refusal to comply in any
material respect with the legal directives of the Board of Directors of Lender
(or any successor entity); (B) dishonest or fraudulent conduct, a deliberate
attempt to do an injury to Lender (or any successor entity), or conduct that
materially harms Lender (or any successor entity) or is materially detrimental
to the reputation of Lender (or any successor entity), including any felony
conviction; or (C) a breach of any element of the Employee Inventions and
Proprietary Rights Assignment Agreement between the Lender

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and the Borrower dated September 25, 1998, including without limitation, theft
or other misappropriation of proprietary information of Lender (or any successor
entity).

          (e)  For the purposes hereof, "Good Reason" means (A) a material
adverse change in Borrower's position; (B) a reduction in Borrower's base
salary, unless such reduction is in connection with similar decreases of the
other members of the management team of Lender; or (C) without Borrower's prior
written consent, a requirement by Lender (or any successor entity) that he
relocate to a facility more than fifty (50) miles from his current principal
workplace.

     2.   Governing Law. This Note shall be governed by California law, without
giving effect to conflicts of law principles.

     3.   Borrower Waivers. Borrower waives presentment, diligence, demand of
payment, notice, protest and all other demands and notices in connection with
the delivery, acceptance, performance, default or enforcement of this Note. In
any action on this Note, Lender need not produce or file the original of this
Note, but need only file a photocopy of this Note certified by Lender be a true
and correct copy of this Note in all material respects.

     4.   Enforcement Costs. Borrower shall pay all costs and expenses,
including, without limitation, reasonable attorneys' fees and expenses Lender
expends or incurs in connection with the enforcement of this Note, the
collection of any sums due under this Note, any actions for declaratory relief
in any way related to this Note, or the protection or preservation of any rights
of the holder under this Note.

     5.   Entire Agreement. This Note and the Pledge Agreement constitute the
entire agreement between Borrower and Lender with respect to the subject matter
hereof and supersede all prior or contemporaneous negotiations, communications,
discussions and correspondence concerning the subject matter hereof, including,
without limitation, the memorandum from Mahmood Panjwani to Mark Culhane dated
October 31, 2000.

     6.   Headings. Section headings used in this Note have been set forth
herein for convenience of reference only. Unless the contrary is compelled by
the context, everything contained in each section hereof applies equally to this
entire Note.


                                       /s/ MARK CULHANE
                                       ------------------------------------
                                       MARK CULHANE

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