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                                                                   EXHIBIT 10.16


                                  VIADOR INC.
                                  -----------

                             STOCK PLEDGE AGREEMENT
                             ----------------------


          AGREEMENT made as of this 26th day of May 2000, by and between Viador
Inc., a Delaware corporation (the "Corporation"), and Raja H. Venkatesh
("Pledgor").

RECITALS
--------

          A.   In connection with the purchase of Forty-Five Thousand (45,000)
shares of the Corporation's Common Stock (the "Purchased Shares") on the date of
this Agreement from the Corporation and for the taxes incurred in connection
with the purchase of such Purchased Shares, Pledgor has issued that certain Note
Secured by Stock Pledge Agreement dated May 26, 2000, payable to the order of
the Corporation in the principal amount of Two Hundred Fifty-Five Thousand Seven
Hundred Seventy-Seven Dollars and Sixty-Five Cents ($255,777.65)  (the "Note").

          B.   Such Note is secured by the Purchased Shares and other collateral
upon the terms set forth in this Agreement.

          NOW, THEREFORE, it is hereby agreed as follows:

          1.  Grant of Security Interest.  Pledgor hereby grants the Corporation
              --------------------------
a security interest in, and assigns, transfers to and pledges with the
Corporation, the following securities and other property (collectively, the
"Collateral"):

               (i)   the Purchased Shares delivered to and deposited with the
     Corporation as collateral for the Note;

               (ii)  any and all new, additional or different securities or
     other property subsequently distributed with respect to the Purchased
     Shares which are to be delivered to and deposited with the Corporation
     pursuant to the requirements of Paragraph 3 of this Agreement;

               (iii) any and all other property and money which is delivered to
     or comes into the possession of the Corporation pursuant to the terms of
     this Agreement; and

               (iv)  the proceeds of any sale, exchange or disposition of the
     property and securities described in subparagraphs (i), (ii) or (iii)
     above.

          2.  Warranties.  Pledgor hereby warrants that Pledgor is the owner of
              ----------
the Collateral and has the right to pledge the Collateral and that the
Collateral is free from all liens, adverse claims and other security interests
(other than those created hereby).
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          3.  Duty to Deliver.  Any new, additional or different securities or
              ---------------
other property (other than regular cash dividends) which may now or hereafter
become distributable with respect to the Collateral by reason of (i) any stock
split, stock dividend, recapitalization, combination of shares, exchange of
shares or other change affecting the Common Stock as a class without the
Corporation's receipt of consideration or (ii) any merger, consolidation or
other reorganization affecting the capital structure of the Corporation shall,
upon receipt by Pledgor, be promptly delivered to and deposited with the
Corporation as part of the Collateral hereunder.  Any such securities shall be
accompanied by one or more properly-endorsed stock power assignments.

          4.  Payment of Taxes and Other Charges.  Pledgor shall pay, prior to
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the delinquency date, all taxes, liens, assessments and other charges against
the Collateral, and in the event of Pledgor's failure to do so, the Corporation
may at its election pay any or all of such taxes and other charges without
contesting the validity or legality thereof; provided however, that the
Corporation shall have provided Pledgor with fifteen (15) days prior written
notice of such election.  The payments so made shall become part of the
indebtedness secured hereunder and until paid shall bear interest at the minimum
per annum rate, compounded semi-annually, required to avoid the imputation of
interest income to the Corporation and compensation income to Pledgor under the
Federal tax laws.

          5.  Shareholder Rights.  So long as there exists no event of default
              -------------------
under Paragraph 10 of this Agreement, Pledgor may exercise all shareholder
voting rights and be entitled to receive any and all regular cash dividends paid
on the Collateral and all proxy statements and other shareholder materials
pertaining to the Collateral.

          6.  Rights and Powers of Corporation.  The Corporation may, without
              --------------------------------
obligation to do so, exercise at any time and from time to time one or more of
the following rights and powers with respect to any or all of the Collateral:

               (i)   subject to the applicable limitations of Paragraph 9,
     accept in its discretion other property of Pledgor in exchange for all or
     part of the Collateral and release Collateral to Pledgor to the extent
     necessary to effect such exchange, and in such event the other property
     received in the exchange shall become part of the Collateral hereunder;

               (ii)  perform such acts as are necessary to preserve and protect
     the Collateral and the rights, powers and remedies granted with respect to
     such Collateral by this Agreement; and

               (iii)  transfer record ownership of the Collateral to the
     Corporation or its nominee and receive, endorse and give receipt for, or
     collect by legal proceedings or otherwise, dividends or other distributions
     made or paid with respect to the Collateral, provided and only if there
                                                  --------------------
     exists at the time an outstanding event of default under Paragraph 10 of
     this Agreement.  Any cash sums which the Corporation may so receive shall
     be applied to the payment of the Note and any other indebtedness secured
     hereunder, in such order of application
<PAGE>

     as the Corporation deems appropriate. Any remaining cash shall be paid over
     to Pledgor.

          Any action by the Corporation pursuant to the provisions of this
Paragraph 6 may be taken only after the Corporation has provided Pledgor with
fifteen (15) days prior written notice of such action.  Expenses reasonably
incurred in connection with such action shall be payable by Pledgor and form
part of the indebtedness secured hereunder as provided in Paragraph 12.

          7.  Care of Collateral.  The Corporation shall exercise reasonable
              ------------------
care in the custody and preservation of the Collateral.  However, the
Corporation shall have no obligation to (i) initiate any action with respect to,
or otherwise inform Pledgor of, any conversion, call, exchange right, preemptive
right, subscription right, purchase offer or other right or privilege relating
to or affecting the Collateral, (ii) preserve the rights of Pledgor against
adverse claims or protect the Collateral against the possibility of a decline in
market value or (iii) take any action with respect to the Collateral requested
by Pledgor unless the request is made in writing and the Corporation determines
that the requested action will not unreasonably jeopardize the value of the
Collateral as security for the Note and other indebtedness secured hereunder.

          Subject to the limitations of Paragraph 9, the Corporation may at any
time release and deliver all or part of the Collateral to Pledgor, and the
receipt thereof by Pledgor shall constitute a complete and full acquittance for
the Collateral so released and delivered.  The Corporation shall accordingly be
discharged from any further liability or responsibility for the Collateral, and
the released Collateral shall no longer be subject to the provisions of this
Agreement.

          8.  Transfer of Collateral.  In connection with the transfer or
              ----------------------
assignment of the Note (whether by negotiation, discount or otherwise), the
Corporation may transfer all or any part of the Collateral, and the transferee
shall thereupon succeed to all the rights, powers and remedies granted the
Corporation hereunder with respect to the Collateral so transferred. Upon such
transfer, the Corporation shall be fully discharged from all liability and
responsibility for the transferred Collateral.

          9.  Release of Collateral.  Provided all indebtedness secured
              ---------------------
hereunder (other than payments not yet due and payable under the Note) shall at
the time have been paid in full and there does not otherwise exist any event of
default under Paragraph 10, the Purchased Shares, together with any additional
Collateral which may hereafter be pledged and deposited hereunder, shall be
released from pledge and returned to Pledgor in accordance with the following
provisions:

               (i) Upon payment or prepayment of principal under the Note,
     together with payment of all accrued interest to date on the principal
     amount so paid or prepaid, one or more of the Purchased Shares held as
     Collateral hereunder shall (subject to the applicable limitations of
     Paragraphs 9(iii) and 9(v) below) be released at the time of such payment
     or prepayment.  The number of the shares to be so released shall be equal
     to the number obtained by multiplying
<PAGE>

     (i) the total number of Purchased Shares held under this Agreement at the
     time of the payment or prepayment, by (ii) a fraction, the numerator of
     which shall be the amount of the principal paid or prepaid and the
     denominator of which shall be the unpaid principal balance of the Note
     immediately prior to such payment or prepayment. In no event, however,
     shall any fractional shares be released.

               (ii)  Any additional Collateral which may hereafter be pledged
     and deposited with the Corporation (pursuant to the requirements of
     Paragraph 3) with respect to the Purchased Shares shall be released at the
     same time the particular shares of Common Stock to which the additional
     Collateral relates are to be released in accordance with the applicable
     provisions of Paragraph 9(i).

               (iii)  Under no circumstances, however, shall any Purchased
     Shares or any other Collateral be released if previously applied to the
     payment of any indebtedness secured hereunder.  In addition, in no event
     shall any Purchased Shares or other Collateral be released pursuant to the
     provisions of Paragraph 9(i) or 9(ii) if, and to the extent, the fair
     market value of the Common Stock and all other Collateral which would
     otherwise remain in pledge hereunder after such release were effected would
     be less than the unpaid principal and accrued interest under the Note.

               (iv) For all valuation purposes under this Agreement, the fair
     market value per share of Common Stock on any relevant date shall be
     determined in accordance with the following provisions:

                    (A)  If the Common Stock is at the time traded on the Nasdaq
     National Market, the fair market value shall be the closing selling price
     per share of Common Stock on the date in question, as such prices are
     reported by the National Association of Securities Dealers on the Nasdaq
     National Market and published in The Wall Street Journal.  If there is no
                                      -----------------------
     reported closing selling price for the Common Stock on the date in
     question, then the closing selling price on the last preceding date for
     which such quotation exists shall be determinative of fair market value.

                    (B)  If the Common Stock is at the time listed on the
     American Stock Exchange or the New York Stock Exchange, then the fair
     market value shall be the closing selling price per share of Common Stock
     on the date in question on the securities exchange serving as the primary
     market for the Common Stock, as such price is officially quoted in the
     composite tape of transactions on such exchange and published in The Wall
                                                                      --------
     Street Journal. If there is no reported sale of Common Stock on such
     --------------
     exchange on the date in question, then the fair market value shall be the
     closing selling price on the exchange on the last preceding date for which
     such quotation exists.
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                    (C) If the Common Stock is at the time neither listed on any
     securities exchange nor traded on the Nasdaq National Market, the fair
     market value shall be determined by the Corporation's Board of Directors
     after taking into account such factors as the Board shall deem appropriate.

               (v) So long as the Collateral is in whole or in part comprised of
     "margin stock" within the meaning of Section 221.2 of Regulation U of the
     Federal Reserve Board, no Collateral shall be substituted for any
     Collateral under the provisions of Paragraph 6(i) or be released under
     Paragraph 9(i) or (ii),  unless there is compliance with each of the
     following additional requirements:

                    (A) The substitution or release must not increase the amount
     by which the indebtedness secured hereunder at the time of such
     substitution or release exceeds the maximum loan value (as defined below)
     of the Collateral immediately prior to such substitution or release.

                    (B) The substitution or release must not cause the amount of
     indebtedness secured hereunder at the time of such substitution or release
     to exceed the maximum loan value of the Collateral remaining after such
     substitution or release is effected.

                    (C) For purposes of this Paragraph 9(v), the maximum loan
     value of each item of Collateral shall be determined on the day the
     substitution or release is to be effected and shall, in the case of the
     pledged shares of Common Stock and any additional Collateral (other than
     margin stock), equal the good faith loan value thereof (as defined in
     Section 221.2 of Regulation U) and shall, in the case of all margin stock
     (other than the pledged shares of Common Stock), equal fifty percent (50%)
     of the current market value of such stock.

          10.  Events of Default.  The occurrence of one or more of the
               -----------------
following events shall constitute an event of default under this Agreement:

               (i) the failure of Pledgor to pay, when due under the Note, any
     installment of accrued interest or principal; or

               (ii) the occurrence of any other acceleration event specified in
     the Note; or

               (iii)  the failure of Pledgor to perform any obligation imposed
     upon Pledgor by reason of this Agreement; or

               (iv) the breach of any warranty of Pledgor contained in this
     Agreement.
<PAGE>

          Upon the occurrence of any such event of default, the Corporation may,
at its election, declare the Note and all other indebtedness secured hereunder
to become immediately due and payable and may exercise any or all of the rights
and remedies granted to a secured party under the provisions of the California
Uniform Commercial Code (as now or hereafter in effect), including (without
limitation) the power to dispose of the Collateral by public or private sale or
to accept the Collateral in full payment of the Note and all other indebtedness
secured hereunder.

          Any proceeds realized from the disposition of the Collateral pursuant
to the foregoing power of sale shall be applied first to the payment of expenses
incurred by the Corporation in connection with the disposition, then to the
payment of the Note and finally to any other indebtedness secured hereunder.
Any surplus proceeds shall be paid over to Pledgor.  However, in the event such
proceeds prove insufficient to satisfy all obligations of Pledgor under the
Note, then Pledgor shall remain personally liable for the resulting deficiency.

          11.  Other Remedies.  The rights, powers and remedies granted to the
               --------------
Corporation pursuant to the provisions of this Agreement shall be in addition to
all rights, powers and remedies granted to the Corporation under any statute or
rule of law.  Any forbearance, failure or delay by the Corporation in exercising
any right, power or remedy under this Agreement shall not be deemed to be a
waiver of such right, power or remedy.  Any single or partial exercise of any
right, power or remedy under this Agreement shall not preclude the further
exercise thereof, and every right, power and remedy of the Corporation under
this Agreement shall continue in full force and effect unless such right, power
or remedy is specifically waived by an instrument executed by the Corporation.

          12.  Costs and Expenses.  All costs and expenses (including reasonable
               ------------------
attorneys fees) incurred by the Corporation in the exercise or enforcement of
any right, power or remedy granted it under this Agreement shall become part of
the indebtedness secured hereunder and shall constitute a personal liability of
Pledgor payable immediately upon demand and bearing interest until paid at the
minimum per annum rate, compounded semi-annually, required to avoid the
imputation of interest income to the Corporation and compensation income to
Pledgor under the Federal tax laws.

          13.  Applicable Law.  This Agreement shall be governed by and
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construed in accordance with the laws of the State of California without resort
to that State's conflict-of-laws rules.

          14.  Successors.  This Agreement shall be binding upon the Corporation
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and its successors and assigns and upon Pledgor and the executors, heirs and
legatees of Pledgor's estate.

          15.  Severability.  If any provision of this Agreement is held to be
               ------------
invalid under applicable law, then such provision shall be ineffective only to
the extent of such invalidity, and neither the remainder of such provision nor
any other provisions of this Agreement shall be affected thereby.
<PAGE>

          IN WITNESS WHEREOF, this Agreement has been executed by Pledgor and
the Corporation on this 26th day of May 2000.


                                       /s/ Raja H. Venkatesh
                                       -----------------------------------
                                       RAJA H. VENKATESH, PLEDGOR

                                       Address:___________________________

                                       ___________________________________



AGREED TO AND ACCEPTED BY:

VIADOR INC.

By: /s/ Stan X. Wang
   ____________________________

Title: President and Chief Executive Officer
      ________________________________________
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                      ASSIGNMENT SEPARATE FROM CERTIFICATE

          FOR VALUE RECEIVED, Raja H. Venkatesh hereby sell(s), assign(s) and

transfer(s) unto Viador Inc. (the "Corporation"),____________________________

__________________________________________________ (____) shares of the Common

Stock of the Corporation standing in his name on the books of the Corporation

represented by Certificate No.____  herewith and do(e)s hereby irrevocably

constitute and appoint _____________ Attorney to transfer the said stock on the

books of the Corporation with full power of substitution in the premises.


Dated: ____________________