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Exhibit 10.20

THE SECURITIES REPRESENTED BY THIS DOCUMENT HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR REGISTERED OR
QUALIFIED UNDER APPLICABLE STATE SECURITIES LAWS IN RELIANCE UPON EXEMPTIONS
THEREFROM. THE HOLDER MAY NOT OFFER, SELL, TRANSFER, ASSIGN, PLEDGE, HYPOTHECATE
OR OTHERWISE DISPOSE OF OR ENCUMBER THE SECURITIES REPRESENTED BY THIS DOCUMENT
EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT
AND THE RULES AND REGULATIONS PROMULGATED THEREUNDER AND IN COMPLIANCE WITH
APPLICABLE STATE SECURITIES LAWS, OR UPON RECEIPT BY THE ISSUER OF AN OPINION OF
LEGAL COUNSEL FOR THE HOLDER REASONABLY SATISFACTORY TO THE ISSUER AND ITS LEGAL
COUNSEL THAT SUCH OFFER, SALE, TRANSFER, ASSIGNMENT, PLEDGE, HYPOTHECATION OR
OTHER DISPOSITION OR ENCUMBRANCE IS EXEMPT FROM THE REGISTRATION PROVISIONS OF
THE SECURITIES ACT AND THE RULES AND REGULATIONS PROMULGATED THEREUNDER AND THE
REGISTRATION AND/OR QUALIFICATION PROVISIONS OF APPLICABLE STATE SECURITIES
LAWS.

MSC.SOFTWARE CORPORATION

WARRANT TO PURCHASE COMMON STOCK
VOID AFTER 5:00 P.M., LOS ANGELES TIME, ON MAY 1, 2007

        This certifies that, for value received, MICHAEL KORYBALSKI or
registered assigns (the "Holder"), is entitled to purchase from MSC.Software
Corporation, a Delaware corporation (the "Company"), at any time on and after
May 1, 2003, but no later than 5:00 P.M., Los Angeles time, on May 1, 2007 (the
"Expiration Date"), at the purchase price of $15.00 per share (the "Exercise
Price"), up to 15,000 shares of Common Stock, par value $0.01 per share, of the
Company (the "Warrant Shares"). The number of Warrant Shares purchasable upon
exercise of this Warrant and the Exercise Price per share are subject to
adjustment from time to time as set forth in this Warrant.

SECTION 1. Exercise

        1.1    Exercise. This Warrant may be exercised in whole or in part by
presentation of this Warrant with the Purchase Form attached hereto duly
executed and simultaneous payment of the Exercise Price (subject to adjustment)
at the principal executive offices of the Company, currently in the City of
Santa Ana, California. Payment of the Exercise Price shall be made at the option
of the Holder hereof by certified or cashier's check or as provided in
subsection 1.2 hereof. Upon any partial exercise of this Warrant, there shall be
countersigned and issued to the Holder hereof a new Warrant in respect of the
Warrant Shares as to which this Warrant shall not have been exercised.

        1.2    Alternative Exercise. In lieu of exercising this Warrant for cash
as described in subsection 1.1, the Holder shall have the right to exercise this
Warrant or any portion thereof (the "Net Issuance Right") into shares of Common
Stock as provided in this subsection 1.2 at any time or from time to time during
the period specified in the first paragraph of this Warrant by the surrender of
this Warrant (properly endorsed) to the Company. Upon exercise of the Net
Issuance Right with respect to a particular number of shares subject to this
Warrant (the "Net Issuance Warrant Shares"), the Company shall deliver to the
Holder (without payment by the Holder of any Exercise Price or any cash or other
consideration) that number of shares of Common Stock equal to the quotient
obtained by dividing (X) the value of this Warrant (or the specified portion
hereof) on the Net Issuance Exercise Date, which value shall be determined by
subtracting (A) the aggregate Exercise Price of the Net Issuance Warrant Shares
immediately prior to the exercise of the Net Issuance Right from (B) the
aggregate fair market value of the Net Issuable Warrant Shares issuable

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upon exercise of this Warrant (or the specified portion hereof) on the date the
Net Issuance Right is exercised as provided herein by (Y) the fair market value
of one share of Common Stock on the date the Net Issuance Right is exercised as
provided herein. For purposes of this subsection 1.2, fair market value shall
mean the Closing Price (as defined in subsection 4.1(c)) of the Common Stock on
the date the Net Issuance Right is exercised as provided herein.

        1.3    Effect of Exercise. This Warrant shall be deemed to have been
exercised immediately prior to the close of business on the date of its
surrender for exercise as provided in this Section 1 and the persons entitled to
receive the shares of Common Stock issuable upon such exercise shall be treated
for all purposes as the holders of record of such shares as of the close of
business on such date. As promptly as practicable on or after such date, the
Company at its expense shall issue and deliver to the person or persons entitled
to receive the same a certificate or certificates for the number of shares of
Common Stock issuable upon such exercise.

SECTION 2. Transfer of Exchange of Warrant

        2.1    Transfer. This Warrant shall be transferable only in the books of
the Company upon delivery thereof duly endorsed by the Holder or by his duly
authorized attorney or legal representative. In all cases of transfer by an
attorney, the original power of attorney, duly approved, or an official copy
thereof, duly certified, shall be deposited and remain with the Company. In case
of transfer by executors, administrators, guardians or other legal
representatives, duly authenticated evidence of their authority shall be
produced, and required to be deposited and remain with the Company. Upon any
registration of transfer, the Company shall countersign and deliver a new
Warrant to the person entitled thereto. Transfer of this Warrant can be made
only in compliance with all applicable federal and state securities laws.

        2.2    Exchange of Warrant. This Warrant may be exchanged for another
Warrant entitling the Holder thereof to purchase a like aggregate number of
Warrant Shares as the Warrant surrendered then entitles such Holder to purchase.
Any Holder desiring to exchange this Warrant shall make such request in writing
delivered to the Company, and shall surrender this Warrant. Thereupon, the
Company shall countersign and deliver to the person entitled thereto a new
Warrant as so requested.

SECTION 3. Reservation of Shares of Common Stock

        There have been reserved, and the Company shall at all times keep
reserved out of its authorized Common Stock, a number of shares of Common Stock
sufficient to provide for the exercise of the right of purchase represented by
this Warrant. The Company covenants that all shares of Common Stock issuable
upon exercise of this Warrant will, upon issuance, be duly authorized, validly
issued, fully paid and nonassessable. The transfer agent for the Company's
Common Stock and every subsequent transfer agent for any shares of the Company's
capital stock issuable upon the exercise of any of the rights of purchase
aforesaid will be irrevocably authorized and directed at all times to reserve
such number of authorized shares required for such purpose.

SECTION 4. Adjustment of Exercise Price and Number of Warrant Shares

        4.1    Adjustments. The number and kind of securities purchasable upon
the exercise of this Warrant and the Exercise Price shall be subject to
adjustment as follows:

        (a)  Stock Dividends, Splits, etc. In case the Company shall at any time
after the date of this Warrant (i) pay a dividend or make a distribution on its
Common Stock which is paid or made (A) in Common Stock or other shares of the
Company's capital stock or (B) in rights or warrants to purchase Common Stock or
other capital stock of the Company if such rights or warrants are not
exercisable or separable from the Common Stock except upon the occurrence of a
contingency, (ii) subdivide its outstanding Common Stock into a greater number
of shares of Common Stock, (iii) combine its outstanding shares into a smaller
number of shares of Common Stock or (iv) issue by reclassification of

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its Common Stock other securities of the Company, then, in any such event the
number of Warrant Shares purchasable upon exercise of this Warrant immediately
prior thereto shall be adjusted so that the Holder of this Warrant shall be
entitled to receive, upon exercise of this Warrant, the kind and number of
shares of the Company and rights to purchase Common Stock or other securities of
the Company (or, in the event of the redemption of any such rights, any cash
paid in respect of such redemption) that he, she or it would have owned or been
entitled to receive after the happening of any of the events described above had
this 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 immediately after the opening of business
on the next business day following the record date in the case of dividends or
other distributions and shall become effective immediately after the opening of
business on the next business day following the effective date in the case of a
subdivision or combination.

        (b)  Distributions of Assets. In case the Company shall at any time
after the date of this Warrant distribute to all holders of its Common Stock
evidences of indebtedness of the Company or assets of the Company (including
cash dividends or distributions out of retained earnings other than cash
dividends or distributions made on a quarterly or other periodic basis) or
warrants to subscribe for securities of the Company (excluding those referred to
in paragraph (a) above), then in each case the Exercise Price shall be adjusted
to a price determined by multiplying the Exercise Price in effect immediately
prior to such distribution by a fraction, of which the numerator shall be the
then current Market Price (as defined in paragraph (c) below) per share of
Common Stock on the record date for determination of shareholders entitled to
receive such distribution, less the then fair value (as determined in good faith
by the Board of Directors of the Company, whose determination shall be
conclusive) of the portion of the assets or evidences of indebtedness so
distributed or of such subscription rights or warrants which are applicable to
one share of Common Stock, and of which the denominator shall be such Market
Price per share of Common Stock; provided, however, that if the then current
Market Price per share of Common Stock on the record date for determination of
shareholders entitled to receive such distribution is less than the then fair
value of the portion of the assets or evidences of indebtedness so distributed
or of such subscription rights or warrants which are applicable to one share of
Common Stock, the foregoing adjustment of the Exercise Price shall not be made
and in lieu thereof the Holder shall be entitled to receive upon exercise of
this Warrant in addition to the Common Stock the kind and number of assets,
evidences of indebtedness, subscription rights and warrants (or, in the event of
the redemption of any such evidences of indebtedness, subscription rights and
warrants, any cash paid in respect of such redemption) that he, she or it would
have owned or have been entitled to receive after the happening of such
distribution had this Warrant been exercised immediately prior to the record
date for such distribution. Such adjustment shall be made successively whenever
such a record date is fixed, and in the event that such distribution is not so
made, the Exercise Price shall again be adjusted to be the Exercise Price which
would then be in effect if such record date had not been fixed.

        (c)  Computation of Market Price. For the purpose of any computation
under this Warrant, the current Market Price per share of Common Stock at any
date shall be deemed to be the average of the daily Closing Price per share for
the 15 consecutive Trading Days (as defined below) commencing 30 Trading Days
before the date in question. "Closing Price" is defined as the closing price for
the Common Stock on the New York Stock Exchange. If Closing Price cannot be
established as described above, Market Price shall be the fair market value of
the Common Stock as determined in good faith by the Board of Directors. "Trading
Day" shall mean a day on which the principal national securities exchange on
which the Common Stock is listed or admitted to trading is open for the
transaction of business.

        (d)  Minimum Adjustment. No adjustment in the number of Warrant Shares
purchasable hereunder or the Exercise Price shall be required unless such
adjustment would require an increase or decrease of at least 1.0% in the number
of Warrant Shares purchasable upon the exercise of this Warrant, or the

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Exercise Price, as the case may be; provided, however, that any adjustments
which by reason of this paragraph (d) are not required to be made shall be
carried forward and taken into account in any subsequent adjustment. All
calculations under this Section 4 shall be made to the nearest cent or the
nearest ten-thousandth of a share, as the case may be.

        (e)  Warrant Share Adjustment. Upon each adjustment of the Exercise
Price as a result of the calculations made in paragraph (a) or (b) above, this
Warrant shall thereafter evidence the right to purchase, at the adjusted
Exercise Price, that number of shares (calculated to the nearest ten-thousandth)
obtained by (A) multiplying (x) the number of shares covered by this Warrant
immediately prior to such adjustment of the Exercise Price by (y) the Exercise
Price in effect immediately prior to such adjustment of the Exercise Price and
(ii) dividing the product so obtained by the Exercise Price in effect
immediately after such adjustment of the Exercise Price.

        (f)    Notice of Adjustment. Whenever the number of Warrant Shares
purchasable upon the exercise of this Warrant or the Exercise Price of such
Warrant Shares is adjusted, as herein provided, the Company shall promptly mail
by first class mail, postage prepaid, to the Holder of this Warrant notice of
such adjustment or adjustments. Such certificate shall be conclusive evidence of
the correctness of such adjustment.

        (g)  Definition of Common Stock. For the purpose of this subsection 4.1
the term "Common Stock" shall mean (A) the class of stock designated as the
Common Stock of the Company at the date of this Warrant or (B) any other class
of stock resulting from successive changes or reclassifications of such shares
consisting solely of changes in par value, or from par value to no par value or
from no par value to par value. In the event that at any time, as a result of an
adjustment made pursuant to paragraph (a) above, above, the Holder of this
Warrant shall become entitled to purchase any securities of the Company other
than Common Stock, thereafter the number of such other securities so purchasable
upon exercise of this Warrant and the Exercise Price of such securities shall be
subject to adjustment from time to time in a manner and on terms as nearly
equivalent as practicable to the provisions with respect to the Warrant Shares
contained in this subsection 4.1 and the provisions of subsections 4.2 and 4.3,
inclusive, with respect to the Warrant Shares, shall apply on like terms to any
such other securities.

        (h)  Company May Reduce Exercise Price or Increase Number of Warrant
Shares Purchasable. The Company may, at its option, at any time during the term
of this Warrant, reduce the then current Exercise Price, or increase the number
of Common Shares purchasable upon exercise of this Warrant, to any amount deemed
appropriate by the Board of Directors of the Company.

        4.2    No Adjustment for Dividends. Except as provided in subsection
4.1, no adjustment in respect of any dividends made on a quarterly or other
periodic basis out of retained earnings shall be made during the term of this
Warrant or upon the exercise of this Warrant.

        4.3    Preservation of Purchase Rights and Adjustment of Exercise Price
upon Merger, Consolidation, etc. In case the Company shall consolidate or merge
with or into any other corporation (other than a consolidation or merger in
which the Company is the surviving corporation and each share of Common Stock
outstanding immediately prior to such consolidation or merger is to remain
outstanding immediately after such consolidation or merger and no cash,
securities or other property is distributed with respect to such shares) or
shall sell or transfer all or substantially all of its assets to any person or
entity, the Company or such successor or purchasing person or entity, as the
case may be (collectively, the "acquiring person"), shall execute an agreement
that the Holder shall have the right thereafter upon payment of the Exercise
Price in effect immediately prior to such action to purchase upon exercise of
this Warrant the kind and amount of shares and other securities, cash and other
property that he, she or it would have owned or have been entitled to receive
after the happening of such consolidation, merger or sale had this Warrant been
exercised immediately prior to such action (assuming that such Holder, as a
holder of Common Stock prior to such action, would not have exercised any rights
of election as a holder of Common Stock as to the kind or amount of securities,
cash or other property receivable upon such consolidation, merger or sale;
provided,

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that if the kind or amount of securities, cash or other property receivable upon
such consolidation, merger or sale is not the same for each non-electing share
of Common Stock, then the kind and amount of securities, cash or other property
receivable shall be deemed to be the kind and amount so receivable by a
plurality of the non-electing shares). The provisions of this subsection 4.3
shall similarly apply to successive consolidations, mergers, sales or
conveyances.

SECTION 5. No Rights as Stockholders

        Nothing contained in this Warrant shall be construed as conferring upon
the Holder or his, her or its transferee the right to vote or to receive
dividends or to consent or to receive notice as shareholders in respect of any
meeting of shareholders for the election of directors of the Company or any
other matter, or any rights whatsoever as shareholders of the Company.

SECTION 6. Fractional Shares of Common Stock

        The Company will not issue fractions of Warrant Shares. In lieu of such
fractional Warrant Shares, there shall be paid to the Holder to whom fractional
Warrant Shares would otherwise be issuable an amount in cash equal to the
product of such fraction of a Warrant Share multiplied by the Closing Price per
share of Common Stock on the date this Warrant is exercised.

SECTION 7. Notices

        Any notice pursuant to this Warrant by the Holder to the Company shall
be in writing and shall be deemed to have been duly given if delivered or mailed
by certified mail, return receipt requested, to MSC.Software Corporation, 2
MacArthur Place, Santa Ana, California 92707, Attention: Louis A. Greco. Any
notice mailed pursuant to this Warrant by the Company to the Holder shall be in
writing and shall be deemed to have been duly given if mailed by first-class
mail, postage prepaid, to Holder at his, her or its address as it appears on the
books of the Company. Each party hereto may from time to time change the address
to which notices to it are to be delivered or mailed hereunder by notice in
writing to the other party.

SECTION 8. Applicable Law

        This Warrant shall be deemed to be a contract made under the internal
laws of the State of California (without preference to conflicts of law
principles) and for all purposes shall be construed in accordance with the laws
of said State.

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

Dated:   MSC.SOFTWARE CORPORATION
 
 
By:
 
/s/  FRANK PERNA      

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Title:
 
 
ATTEST:
 
/s/  MARGARET WILLIAMS      

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Title:

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MSC.SOFTWARE CORPORATION
PURCHASE FORM

        The undersigned hereby irrevocably elects to exercise the right of
purchase represented by the within Warrant for, and to purchase thereunder,
             shares of Common Stock, provided for therein, and requests that
certificates for such shares of Common Stock be issued in the name of:

Name:  

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Address:  

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Social Security or Taxpayer's Identification Number:  

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and, if said number of shares of Common Stock shall not be all the Common Stock
purchasable thereunder, that a new Warrant for the balance remaining of the
Common Stock purchasable under the within Warrant be registered in the name of
the undersigned Warrantholder or his or her Assignee as below indicated and
delivered to the address stated below.

Name of Warrantholder or Assignee:  

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Address:  

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Social Security or Taxpayer's Identification Number:  

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Signature:  

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    Dated:  

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    Signature Guaranteed:

    NOTICE:   The above signature must correspond with the name as written upon
the face of this Warrant in every particular, without alteration or enlargement
or any change whatever, unless this Warrant has been assigned.

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ASSIGNMENT

(To be signed only upon
assignment of Warrant)

        FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto

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(Name of Assignee)

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(Address and Social Security or other Taxpayer Identification Number of
Assignee)

the within Warrant, hereby irrevocably constituting and appointing

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Attorney to transfer said Warrant on the books of the Company, with full power
of substitution in the premises.

DATED:                                         

   

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Signature of Registered Holder

Signature Guaranteed:

    NOTICE:   The signature of this assignment must correspond with the name as
it appears upon the face of the within Warrant in every particular, without
alteration or enlargement or any change whatever.

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MSC.SOFTWARE CORPORATION
WARRANT TO PURCHASE COMMON STOCK VOID AFTER 5:00 P.M., LOS ANGELES TIME, ON MAY
1, 2007
MSC.SOFTWARE CORPORATION PURCHASE FORM