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                                                                    Exhibit 10.1


                            ONYX SOFTWARE CORPORATION

                         COMMON STOCK PURCHASE AGREEMENT


      This Common Stock Purchase Agreement (this "Agreement") is entered into
this 12th day of May, 2005, by and between Onyx Software Corporation, a
Washington corporation (the "Company"), and the investors listed on Schedule A
to this Agreement (collectively, the "Investors").

                                    RECITALS

      The Company desires to issue and sell to the Investors, and the Investors
desire to purchase from the Company, shares of common stock of the Company, par
value $0.01 per share (the "Company Common Stock"), including the associated
preferred share purchase rights (the "Rights") issued pursuant to the Rights
Agreement, dated as of October 25, 1999, between the Company and ChaseMellon
Shareholder Services, L.L.C., on the terms and conditions set forth herein (such
issuance and sale being hereinafter referred to as the "Issuance" and the
Company Common Stock (together with the associated Rights) purchased and sold
hereunder being hereafter referred to as the "Shares").

                                    AGREEMENT

      NOW THEREFORE, in consideration of the foregoing premises and other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto, intending to be legally bound, agree as
follows:

      1. DEFINITIONS.

            "1933 Act" means the U.S. Securities Act of 1933, as amended,
and the rules and regulations promulgated thereunder.

            "1934 Act" means the U.S. Securities Exchange Act of 1934, as
amended, and the rules and regulations promulgated thereunder.

            "GAAP" means United States generally accepted accounting principles.

            "Issuance Price" means $2.78, which price is equal to the greatest
of (i) the closing bid price of the Common Stock on Nasdaq on the Preceding
Closing Date, (ii) the Company's book value per share as of the date of this
Agreement and (iii) the average of the closing bid prices of the Common Stock on
Nasdaq on each of the four trading days immediately preceding and including the
Preceding Closing Date.

            "Knowledge" means (i) with respect to any natural person, the actual
knowledge, after reasonable inquiry, of such person or (ii) with respect to any
corporation or entity, the actual knowledge of such party's executive officers
and directors.
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            "Material Adverse Effect" means a material adverse effect on the
condition (financial or otherwise), business, assets or results of operations of
the Company and its subsidiaries, taken as a whole.

            "Nasdaq" means the Nasdaq National Market.

            "Person" means an individual, corporation, partnership, association,
trust or other entity or organization, including a government or political
subdivision or an agency or instrumentality thereof.

            "Preceding Closing Date" means the close of regular hours trading on
Nasdaq that immediately precedes the time of execution of this Agreement. For
the avoidance of doubt, if this Agreement is executed after the time of close of
trading on Nasdaq, the Preceding Closing Date shall be the date of execution,
and if this Agreement is executed during regular hours trading on Nasdaq, the
Preceding Closing Date shall be the date immediately preceding the date of
execution.

            "SEC" means the United States Securities and Exchange
Commission.

            "SEC Documents" means (i) the Company's annual report on Form 10-K
for its fiscal year ended December 31, 2004, (ii) the Company's proxy statement
relating to its 2005 annual meeting of shareholders, and (iii) all of the
Company's quarterly reports on Form 10-Q and current reports on Form 8-K filed
with the SEC since December 31, 2004.

            "Transfer" means to sell, assign, pledge, encumber or otherwise
transfer or dispose of, for consideration or otherwise, whether voluntarily,
involuntarily or by operation of law.

      2. AGREEMENT TO ISSUE AND RECEIVE.

            (a) Authorization of Shares. The Company has authorized the Issuance
of the Shares.

            (b) Purchase and Sale; Issuance. Subject to the terms and conditions
hereof, at the Closing (as hereinafter defined), the Company hereby agrees to
sell and issue to the Investors, and each Investor, severally and not jointly,
agrees to purchase at the Issuance Price, that number of Shares set forth
opposite such Investor's name on Schedule A.

      3. CLOSING AND DELIVERY.

            (a) Closing. The closing of the Issuance of the Shares under this
Agreement (the "Closing") shall take place at the offices of Orrick, Herrington
& Sutcliffe LLP, 719 Second Avenue, Suite 900, Seattle, Washington 98104, on May
17, 2005, or at such other time or place as the Company and the Investors may
mutually agree (such date is referred to herein as the "Closing Date").


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            (b) Delivery. At the Closing, subject to the terms and conditions
hereof, the Company will deliver to each Investor a certificate dated the
Closing Date and representing the number of Shares to be purchased at the
Closing by such Investor, against payment of the purchase price therefor by wire
transfer to the Company of immediately available U.S. dollars.

      4. REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company hereby
represents and warrants to each Investor that, except as otherwise disclosed in
the SEC Documents:

            (a) Organization, Good Standing and Qualification. The Company is a
corporation duly organized and validly existing under the laws of the state of
Washington and has paid all excise taxes required by the Washington Department
of Revenue. The Company has all requisite corporate power and authority to own
and operate its properties and assets, to execute and deliver this Agreement and
to issue and sell the Shares and to carry on its business as presently conducted
and as presently proposed to be conducted. The Company is duly qualified and is
authorized to do business and is in good standing as a foreign corporation in
all jurisdictions in which the nature of its activities and of its properties
(both owned and leased) makes such qualification necessary, except for those
jurisdictions in which failure to so qualify would not have a Material Adverse
Effect.

            (b) Capitalization. The authorized capital stock of the Company
consists of 100,000,000 shares, consisting of 80,000,000 shares of Company
Common Stock and 20,000,000 shares of preferred stock, par value $0.01 per share
(the "Company Preferred Stock"). As of May 10, 2005, (i) 14,986,285 shares of
Company Common Stock were issued and outstanding, (ii) no shares of Company
Preferred Stock were issued and outstanding, (iii) options to purchase 4,772,318
shares of Company Common Stock were reserved for issuance under the Company's
Amended and Restated 1994 Combined Incentive and Nonqualified Stock Option Plan
and the Company's 1998 Stock Incentive Compensation Plan, of which options to
purchase an aggregate of 2,990,416 shares were outstanding, (iv) 411,312 shares
of Company Common Stock were reserved for issuance under the Company's 1998
Employee Stock Purchase Plan (the "ESPP"), (v) options to purchase 1,472,444
shares of Company Common Stock were reserved for issuance under the Company's
2001 Nonofficer Employee Stock Option Plan and upon exercise of options granted
outside of any plans, of which options to purchase an aggregate of 1,125,101
shares were outstanding, and (vi) 205,000 shares of Company Common Stock were
reserved for issuance upon the exercise of warrants. Except as set forth in this
Section 4(b) and as contemplated by this Agreement, except for rights to
purchase Company Common Stock under the ESPP, except for the Rights, and except
as otherwise disclosed in the SEC Documents, there are no options, warrants,
conversion privileges, preemptive rights, or other rights or agreements to
purchase or otherwise acquire or issue any equity securities of the Company. The
Company has no obligation to repurchase or redeem any outstanding securities.

            (c) Listing Qualifications. The Company Common Stock is quoted and
traded on Nasdaq, no suspension of trading in the Company Common Stock is in
effect or, to the Company's knowledge, threatened, and the Company Common Stock
meets the criteria for listing and trading on Nasdaq.


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            (d) Authorization; Binding Obligations. All corporate action on the
part of the Company and its officers, directors and shareholders necessary for
the authorization of this Agreement, the performance of all obligations of the
Company hereunder at the Closing and the authorization, issuance and delivery of
the Shares pursuant hereto has been taken. This Agreement, when executed and
delivered, will be a valid and legally binding obligation of the Company
enforceable in accordance with its terms, except as limited by (i) applicable
bankruptcy, insolvency, reorganization, moratorium or other laws of general
application affecting enforcement of creditors' rights and (ii) general
principles of equity that restrict the availability of equitable remedies.

            (e) Outstanding Shares; Shares. All outstanding shares of capital
stock of the Company are, and the Shares when delivered to the Investors in
compliance with this Agreement will be, duly authorized, validly issued, fully
paid and nonassessable, free of any liens and not subject to preemptive rights
created by statute, the Restated Articles of Incorporation or Restated Bylaws of
the Company or any agreement or document to which the Company is a party or by
which it is bound; provided, however, that the Shares may be subject to
restrictions on Transfer under state and/or federal securities laws as set forth
herein or as otherwise required by such laws at the time a Transfer is proposed.

            (f) Governmental Authorization. The execution, delivery and
performance by the Company of this Agreement require no action by or in respect
of, or filing with, any governmental body, agency or official of the United
States or the state of Washington, other than compliance with any applicable
requirements of the 1933 Act, the 1934 Act or other applicable U.S. state
securities laws.

            (g) SEC Filings. The Company has filed all forms, reports and
documents required to be filed by it with the SEC and has made available to each
Investor (including via EDGAR) the SEC Documents. As of their respective filing
dates, the SEC Documents (i) were prepared in accordance in all material
respects with the requirements of the 1933 Act or the 1934 Act, as the case may
be, and the rules and regulations thereunder, (ii) did not at the time they were
filed contain any untrue statement of a material fact or omit to state a
material fact required to be stated therein or necessary in order to make the
statements therein, in light of the circumstances under which they were made,
not misleading, and (iii) did not at the time they were filed omit any documents
required to be filed as exhibits thereto.

            (h) Financial Statements. The audited consolidated financial
statements and unaudited interim consolidated financial statements of the
Company included in the SEC Documents present fairly, in all material respects,
the financial position of the Company as of the dates thereof and its results of
operations and changes in financial position for the periods then ended in
conformity with GAAP applied on a consistent basis (subject to normal year-end
adjustments in the case of the unaudited interim financial statements and, with
respect to the unaudited interim consolidated financial statements, the absence
of footnotes required to be included in the audited consolidated financial
statements by GAAP).

            (i) Absence of Certain Changes. Since December 31, 2004, to the
Company's knowledge, there has not been any change that, by itself or in
conjunction with all


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other such changes, has had or reasonably would be expected to have a Material
Adverse Effect, except as disclosed in the SEC Documents to the date of this
Agreement.

            (j) Title to Properties and Assets; Liens, Etc. The Company and each
of its subsidiaries has good and marketable title to its properties and assets
and good title to its leasehold estates, in each case subject to no liens or
encumbrances, other than (i) those resulting from taxes that have not yet become
delinquent, (ii) minor liens that do not materially detract from the value of
the property subject thereto or materially impair the operations of the Company,
and (iii) those that have otherwise arisen in the ordinary course of business.

            (k) Compliance With Other Instruments. The Company is not in
violation or default of any term of its Restated Articles of Incorporation or
Restated Bylaws, or any provision of any mortgage, indenture, contract,
agreement, instrument or contract to which it is party or by which it is bound
or of any judgment, decree, order, writ or any statute, rule or regulation
applicable to the Company, except for such violations or defaults as would not
have a Material Adverse Effect. The execution, delivery and performance of and
compliance with this Agreement and the issuance of the Shares pursuant hereto
will not result in any such material violation, or be in conflict with or
constitute a material default under any such term, or result in the creation of
any lien or encumbrance on any of the properties or assets of the Company or the
suspension, revocation, impairment, forfeiture or nonrenewal of any material
permit, license, authorization or approval applicable to the Company, its
business or operations or any of its assets or properties. There is no such
violation or default or event that, with the passage of time or giving of notice
or both, would constitute a violation or default that would have a Material
Adverse Effect.

            (l) Litigation. Except as disclosed in the SEC Documents, there is
no action, suit, proceeding or investigation pending or, to the Company's
knowledge, currently threatened in writing against the Company that questions
the validity of this Agreement or the right of the Company to enter into this
Agreement, or to consummate the transactions contemplated hereby, or that might
result, either individually or in the aggregate, in a Material Adverse Effect.
Except as disclosed in the SEC Documents, the Company is not a party or subject
to the provisions of any order, writ, injunction, judgment or decree of any
court or government agency or instrumentality.

            (m) Intellectual Property. The Company knows of no adverse claim
that would interfere with its right to use and, to the Company's knowledge, the
Company has sufficient title and ownership of or rights to use all trademarks,
service marks, trade names, copyrights, inventions, trade secrets, licenses,
information and other intellectual property rights necessary to conduct its
business without any violation or infringement of any such intellectual property
rights of others. The Company has not received any communications alleging that
the Company has violated any of the patents, trademarks, service marks, trade
names, copyrights or trade secrets or other intellectual property rights of any
other Person, except for any allegations as would not reasonably be expected to
have a Material Adverse Effect. To the Company's knowledge, all data,
information, ideas, concepts, know-how and materials that the Company treats as
trade secrets, and all other confidential information and intellectual property
rights of the Company, are not part of the public domain or knowledge, nor, to
its knowledge, have they been used,


                                      -5-
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divulged or appropriated for the benefit of any Person other than the Company or
otherwise to the detriment of the Company.

            (n) Compliance With Laws. The Company is in compliance with all
federal, state, local and foreign laws, rules, regulations, ordinances, decrees
and orders applicable to it, to its employees or to its real and personal
property, including, without limitation, all such laws, rules, regulations,
ordinances, decrees and orders relating to intellectual property protection,
antitrust matters, consumer protection, currency exchange, environmental
protection, equal employment opportunity, health and occupational safety,
pension and employee benefit matters, securities and investor protection
matters, labor and employment matters and trading-with-the-enemy matters, except
where the failure of the Company to so comply would not have a Material Adverse
Effect. The Company has not received any notification of any asserted present or
past unremedied failure by the Company to comply with any of such laws, rules,
regulations, ordinances, decrees or orders.

            (o) Brokerage and Finders' Fees. The Company has not incurred, nor
will it incur, directly or indirectly, any liability for brokerage or finders'
fees or agents' commissions or investment bankers' fees or any similar charges
in connection with this Agreement or any transaction contemplated by this
Agreement. The Company agrees to indemnify each Investor for any such claims,
losses or expenses resulting from this Agreement or any transaction contemplated
herein.

      5. REPRESENTATIONS AND WARRANTIES OF THE INVESTOR. Each Investor hereby
represents and warrants to the Company as follows:

            (a) Power and Authority. Such Investor has all requisite power and
authority to execute and deliver this Agreement and to purchase the Shares.

            (b) Authorization; Binding Obligations. If such Investor is not a
natural person, all corporate action on the part of such Investor, its officers,
directors and shareholders or other constituent owners necessary for the
authorization of this Agreement, and the performance of all obligations of the
Investor hereunder at the Closing, has been taken or will be taken prior to the
Closing. This Agreement, when executed and delivered, will be a valid and
legally binding obligation of the Investor enforceable in accordance with its
terms, except (i) as limited by applicable bankruptcy, insolvency,
reorganization, moratorium or other laws of general application affecting
enforcement of creditors' rights and (ii) general principles of equity that
restrict the availability of equitable remedies.

            (c) Investment Representations. Such Investor understands that the
Shares have not been registered under the 1933 Act. Such Investor also
understands that the Shares are being offered and sold pursuant to an exemption
from registration contained in the 1933 Act based in part on such Investor's
representations contained in this Agreement. In this regard, such Investor
hereby represents and warrants as follows:

                  (i) Economic Risk of Investment. Such Investor has substantial
experience in evaluating private placement transactions of securities in
companies similar to the


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Company so that it is capable of evaluating the merits and risks of its
investment in the Company. Such Investor must bear the economic risk of this
investment indefinitely unless the Shares are registered pursuant to the 1933
Act, or an exemption from registration is available. Such Investor understands
that the Company has no present intention, or obligation, to register the
Shares. Such Investor also understands that there is no assurance that any
exemption from registration under the 1933 Act will be available and that, even
if available, such exemption may not allow such Investor to Transfer all or any
portion of the Shares under the circumstances, in the amounts or at the times
such Investor might propose.

                  (ii) Acquisition for Own Account. Such Investor is acquiring
the Shares for such Investor's own account, not as a nominee or agent, and not
with a view to, or for resale in connection with, any "distribution" thereof
within the meaning of the 1933 Act. Such Investor has no present intention of
Transferring the Shares. Such Investor further represents that such Investor
does not presently have any contract, undertaking, agreement or arrangement with
any Person to Transfer or grant participation to such Person with respect to any
of the Shares.

                  (iii) Accredited Investor. Such Investor represents that such
Investor is an "accredited investor" within the meaning of Regulation D under
the 1933 Act.

                  (iv) Restricted Securities. Such Investor understands that (A)
the Shares have not been, and will not be, registered under the 1933 Act, (B)
the Shares are "restricted securities" under applicable U.S. federal and state
securities laws and that, pursuant to these laws, such Investor may not transfer
the Shares unless they are registered with the SEC and qualified by state
authorities, or an exemption from such registration and qualification
requirements is available, and (C) the Company has no obligation to register or
qualify the Shares for resale.

                  (v) 1934 Act Filings. Such Investor agrees and acknowledges
that such Investor shall have sole responsibility for making any filings that
may be required with the SEC pursuant to Sections 13 and 16 of the 1934 Act as a
result of such Investor's acquisition of the Shares and any future retention or
transfer thereof.

                  (vi) Rule 144. Such Investor is aware of the provisions of
Rule 144 promulgated under the 1933 Act that permit limited resale of securities
purchased in a private placement subject to the satisfaction of certain
conditions, including, among other things, the existence of a public market for
the securities, the availability of certain public information about the
Company, the resale occurring not less than one year after a party has purchased
and paid for the security to be sold, the sale being effected through a
"broker's transaction" or in transactions directly with a "market maker" and the
number of securities being sold during any three-month period not exceeding
specified limitations.

                  (vii) Access to Information. Such Investor is aware of the
Company's business affairs and financial condition and has acquired sufficient
information about the Company to reach an informed and knowledgeable decision to
acquire the Shares. Such Investor has had an opportunity to discuss the
Company's business, management and financial affairs with its management and an
opportunity to review the Company's facilities and financial data.


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Such Investor has also had an opportunity to ask questions of officers of the
Company, which questions were answered to such Investor's satisfaction. Such
Investor understands that such discussions, as well as any written information
issued by the Company, were intended to describe certain aspects of the
Company's business and prospects but were not a thorough or exhaustive
description, and that no representation or warranty as to the Company's past,
present or future business or operations was intended thereby.

                  (viii) Further Limitations on Disposition. Without in any way
limiting the representations set forth above, such Investor further agrees not
to make any Transfer of all or any portion of the Shares unless and until:

                        (A) there is then in effect a registration statement
under the 1933 Act covering such proposed disposition and such disposition is
made in accordance with such registration statement; or

                        (B) (1) such Investor shall have notified the Company of
the proposed disposition and shall have furnished the Company with a detailed
statement of the circumstances surrounding the proposed disposition and (2) if
requested by the Company, such Investor shall have furnished the Company with an
opinion of counsel, reasonably satisfactory to the Company that such disposition
will not require registration of such shares under the 1933 Act. It is agreed
that the Company will not require opinions of counsel for transactions made
pursuant to Rule 144 except in unusual circumstances.

                  (ix) Broker's Fees. Such Investor has not incurred, nor will
such Investor incur, directly or indirectly, any liability for brokerage or
finders' fees or agents' commission or any similar charges in connection with
this Agreement or any transaction contemplated by this Agreement that would
result in a claim against the Company. Such Investor agrees to indemnify the
Company for any such claims, losses or expenses resulting from this Agreement or
any transaction contemplated hereby.

                  (x) Investor Counsel. Such Investor acknowledges that such
Investor has had an opportunity to review this Agreement and the schedule
attached hereto and the transactions contemplated by this Agreement with such
Investor's own legal counsel. Such Investor is relying solely on such Investor's
legal counsel and not on the Company or any of the Company's agents, including
Orrick, Herrington & Sutcliffe LLP, for legal advice with respect to this
investment or the transactions contemplated by this Agreement.

                  (xi) Residency. Such Investor is a resident of the U.S. state
set forth in Schedule A to this Agreement.

                  (xii) No Intent to Effect a Change of Control. Such Investor
has no present intent to change or influence control of the Company within the
meaning of Rule 13d of the 1934 Act. Such Investor does not, prior to the
Closing, beneficially own (as defined in the 1934 Act) more than 10% of the
outstanding voting stock of the Company and will not, after giving effect to the
Closing, beneficially own (as defined in the 1934 Act) more than 15% of the
outstanding voting stock of the Company.


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      6.    OTHER AGREEMENTS.

            (a) Legends. The certificate or certificates representing the
Shares, when issued, shall bear the following or a substantially similar legend:

            "THE SECURITIES EVIDENCED BY THIS CERTIFICATE HAVE NOT BEEN
            REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"),
            OR APPLICABLE STATE SECURITIES LAWS, AND NO INTEREST MAY BE SOLD,
            DISTRIBUTED, ASSIGNED, OFFERED, PLEDGED OR OTHERWISE TRANSFERRED
            UNLESS (A) THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER THE
            ACT AND APPLICABLE STATE SECURITIES LAWS COVERING ANY SUCH
            TRANSACTION INVOLVING SAID SECURITIES, (B) THIS CORPORATION RECEIVES
            AN OPINION OF LEGAL COUNSEL FOR THE HOLDER OF THESE SECURITIES
            SATISFACTORY TO THIS CORPORATION STATING THAT SUCH TRANSACTION IS
            EXEMPT FROM REGISTRATION, OR (C) THIS CORPORATION OTHERWISE
            SATISFIES ITSELF THAT SUCH TRANSACTION IS EXEMPT FROM REGISTRATION."

            (b) Market Stand-Off.

                  (i) In the event that the Company elects to conduct any public
offering subsequent to the date of this Agreement, each Investor hereby agrees
that, during the period beginning on the date that each Investor is informed of
the possibility of such offering and ending either (A) 90 days after the
effectiveness of such offering or (B) the date that the Company's board of
directors determines to abandon such offering, such Investor shall not, to the
extent requested by the Company and the Company's underwriter, directly or
indirectly Transfer (other than to donees who agree to be similarly bound) any
securities of the Company held by it at any time during such period.

                  (ii) In order to enforce the foregoing covenant, the Company
may impose stop-transfer instructions with respect to the Shares and any other
securities of the Company owned by such Investor until the end of such period,
and such Investor agrees that, if so requested, such Investor will execute an
agreement in the form provided by the underwriter containing terms that are
essentially consistent with the provisions of this Section 6(b).

      7.    COVENANTS.

      Each Investor and the Company hereby covenant as follows:

                  (a) Closing Conditions. Each Investor and the Company shall
take all actions necessary and appropriate to cause the conditions set forth in
Section 8 hereof to be satisfied prior to the Closing.

                  (b) Reasonable Efforts. Subject to the terms and conditions of
this Agreement, each Investor and the Company shall use its respective
reasonable commercial


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efforts to take, or cause to be taken, all actions and to do, or cause to be
done, all things necessary or desirable under applicable laws and regulations to
consummate the transactions contemplated by this Agreement. The Company and each
Investor agree to execute and deliver such other documents, certificates,
agreements and other writings and to take such other actions as may be necessary
or desirable in order to consummate or implement expeditiously the transactions
contemplated by this Agreement.

            (c) Certain Filings. The Company and each Investor shall cooperate
with one another (i) in determining whether any action by or in respect of, or
filing with, any governmental body, agency, official or authority is required,
or any actions, consents, approvals or waivers are required to be obtained from
parties to any material contracts, in connection with the consummation of the
transactions contemplated by this Agreement and (ii) in taking such actions or
making any such filings, furnishing information required in connection therewith
and seeking timely to obtain any such actions, consents, approvals or waivers.

      8.    CONDITIONS TO CLOSING.

            (a) Conditions to Each Investor's Obligations at Closing. Each
Investor's obligation to purchase the Shares at the Closing is subject to the
satisfaction or waiver, at or prior to the Closing, of the following conditions:

                  (i) Representations and Warranties True. The representations
and warranties made by the Company in Section 4 hereof shall be true and correct
in all material respects on and as of the Closing Date with the same effect as
though such representations and warranties had been made on and as of the
Closing Date.

                  (ii) Consents, Permits and Waivers. The Company shall have
obtained any and all material consents, permits and waivers necessary or
appropriate for consummation of the transactions contemplated by this Agreement
(except for such as may be properly obtained subsequent to the Closing).

                  (iii) Performance of Obligations. The Company shall have
performed and complied in all material respects with all agreements and
conditions required herein to be performed or complied with by the Company prior
to the Closing.

                  (iv) Government Orders. No U.S. federal or state governmental
authority or agency or commission or U.S. federal or state court of competent
jurisdiction shall have enacted, issued, promulgated, enforced or entered any
law, rule, regulation, executive order, decree, injunction or other order that
is then in effect and has the effect of making illegal the issuance of the
Shares to each Investor as contemplated hereby.

            (b) Conditions to Obligations of the Company. The Company's
obligation to issue the Shares at the Closing is subject to the satisfaction or
waiver, at or prior to the Closing, of the following conditions:

                  (i) Representations and Warranties True. The representations
and warranties made by each Investor in Section 5 hereof shall be true and
correct in all material

                                      -10-
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respects on and as of the Closing Date with the same effect as though such
representations and warranties had been made on and as of the Closing Date.

                  (ii) Consents, Permits and Waivers. The Company shall have
obtained any and all material consents, permits and waivers necessary or
appropriate for consummation of the transactions contemplated by this Agreement
(except for such as may be properly obtained subsequent to the Closing).

                  (iii) Performance of Obligations. Each Investor shall have
performed and complied in all material respects with all agreements and
conditions required herein to be performed or complied with by such Investor on
or before the Closing.

                  (iv) Government Orders. No U.S. federal or state governmental
authority or agency or commission or U.S. federal or state court of competent
jurisdiction shall have enacted, issued, promulgated, enforced or entered any
law, rule, regulation, executive order, decree, injunction or other order that
is then in effect and has the effect of making illegal the issuance of the
Shares by the Company as contemplated hereby.

      9.    MISCELLANEOUS.

            (a) Equitable Remedies. The parties hereto acknowledge and agree
that irreparable damage would occur in the event any of the provisions of this
Agreement were not performed in accordance with their specific terms or were
otherwise breached. Accordingly, it is agreed that the parties shall be entitled
to an injunction or injunctions to prevent or cure breaches of the provisions of
this Agreement and to enforce specifically the terms and provisions of this
Agreement in the United States or any state thereof having jurisdiction, in
addition to any other remedy to which they may be entitled in law or in equity.

            (b) Governing Law; Venue. This Agreement shall be governed in all
respects by the laws of the state of Washington without reference to its
principles of conflicts of laws. The parties irrevocably consent to the
jurisdiction and venue of the state and federal courts located in King County,
Washington in connection with any action relating to this Agreement or the
transactions contemplated hereby.

            (c) Survival. The representations, warranties, covenants and
agreements made herein shall survive the closing of the transactions
contemplated hereby. All statements as to factual matters contained in any
certificate or other instrument delivered by or on behalf of the Company
pursuant hereto in connection with the transactions contemplated hereby shall be
deemed to be representations and warranties by the Company hereunder solely as
of the date of such certificate or instrument.

            (d) Successors and Assigns. The provisions hereof shall inure to the
benefit of, and be binding upon, the successors, assigns, heirs, executors and
administrators of the parties hereto.

            (e) Entire Agreement. This Agreement, Schedule A hereto and the
other documents delivered pursuant hereto constitute the full and entire
understanding and agreement


                                      -11-
<PAGE>
among the parties with regard to the subject matter hereof and thereof and no
party shall be liable or bound to any other in any manner by any
representations, warranties, covenants and agreements except as specifically set
forth herein and therein.

            (f) Severability. In case any provision of this Agreement shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

            (g) Amendment and Waiver. This Agreement may be amended, modified or
waived only upon the written consent of the Company and the Investors holding a
majority of the Shares purchased hereunder.

            (h) Delays or Omissions. It is agreed that no delay or omission to
exercise any right, power or remedy accruing to any party, upon any breach,
default or noncompliance by another party under this Agreement shall impair any
such right, power or remedy, nor shall it be construed to be a waiver of any
such breach, default or noncompliance, or any acquiescence therein, or of or in
any similar breach, default or noncompliance thereafter occurring. All remedies,
either under this Agreement or otherwise afforded to any party, shall be
cumulative and not alternative.

            (i) Notices. All notices required or permitted hereunder shall be in
writing and shall be deemed effectively given: (i) upon personal delivery to the
party to be notified; (ii) when sent by confirmed facsimile if sent during
normal business hours of the recipient or, if not, then on the next business
day; or (iii) upon delivery when sent by express courier with written
verification of receipt. All communications shall be sent to the addresses set
forth on the signature page hereof or at such other address as the Company or
the Investors may designate by ten (10) days' advance written notice to the
other party hereto.

            (j) Expenses. Irrespective of whether the Closing is effected, each
party shall bear all costs and expenses that such party incurs in connection
with this transaction.

            (k) Attorneys' Fees. In the event that any dispute among the parties
to this Agreement should result in litigation, the prevailing party in such
dispute shall be entitled to recover from the losing party all fees, costs and
expenses of enforcing any right of such prevailing party under or with respect
to this Agreement, including, without limitation, such reasonable fees and
expenses of attorneys and accountants, which shall include, without limitation,
all fees, costs and expenses of appeals.

            (l) Titles and Subtitles. The titles of the sections and subsections
of this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

            (m) Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

                            [Signature page follows]


                                      -12-
<PAGE>
      IN WITNESS WHEREOF, the parties hereto have executed this Common Stock
Purchase Agreement as of the date set forth in the first paragraph hereof.

                                    COMPANY:

                                    ONYX SOFTWARE CORPORATION


                                    By:  /s/ Janice P. Anderson
                                    -------------------------------------
                                    Name:  Janice P. Anderson
                                    Title:  President, Chief Executive
                                    Officer and Chair

                                    Address: 1100 112th Avenue NE, Suite 100
                                             Bellevue, WA 98004

                                    Fax:  425-732-2413
<PAGE>
                                    INVESTOR:

                                    TERRI DIAL AND BRIAN T. BURRY,
                                    COMMUNITY PROPERTY


                                    /s/ Terri Dial
                                    -------------------------------------
                                    Terri Dial


                                    /s/ Brian T. Burry
                                    -------------------------------------
                                    Brian T. Burry
<PAGE>
                                    INVESTOR:

                                    TARKOFF LIVING TRUST DTD 12/8/99,
                                    JASMINE A. TARKOFF AND ROBERT M.
                                    TARKOFF AS TRUSTEES


                                    /s/ Jasmine A. Tarkoff
                                    -------------------------------------
                                    Jasmine A. Tarkoff, Trustee


                                    /s/ Robert M. Tarkoff
                                    -------------------------------------
                                    Robert M. Tarkoff, Trustee
<PAGE>
                                    INVESTOR:

                                    ROBERT J. CHAMBERLAIN AND SUSAN A.
                                    CHAMBERLAIN


                                    /s/ Robert J. Chamberlain
                                    -------------------------------------
                                    Robert J. Chamberlain


                                    /s/ Susan A. Chamberlain
                                    -------------------------------------
                                    Susan A. Chamberlain
<PAGE>
                                    INVESTOR:

                                    ELMORE FAMILY INVESTMENTS, LP


                                    /s/ William B. Elmore
                                    -------------------------------------
                                    William B. Elmore, General Partner
<PAGE>
                                   SCHEDULE A

                              SCHEDULE OF INVESTORS


<TABLE>
<CAPTION>
                                                  Number        Purchase Price
              Name and Address                   of Shares           Paid
              ----------------                   ---------           ----
<S>                                              <C>            <C>
  Terri Dial and Brian T. Burry, community        359,712         $999,999.36
                  property
             223 Pacific Avenue
          San Francisco, CA 94115

 Tarkoff Living Trust dtd 12/8/99, Jasmine        93,525          $259,999.50
A. Tarkoff and Robert M. Tarkoff as Trustees
               c/o Documentum
          6801 Koll Center Parkway
            Pleasanton, CA 94566

     Robert J. Chamberlain and Susan A.           50,000           $139,000
                Chamberlain
       c/o Onyx Software Corporation
       1100 112th Ave. NE, Suite 100
             Bellevue, WA 98004

       Elmore Family Investments, LP             2,321,860       $6,454,770.80
         70 Willow Road, Suite 200
            Menlo Park, CA 94025

                   TOTAL                         2,825,097       $7,853,769.66
</TABLE>