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SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.          )

Filed by the Registrant o

Filed by a Party other than the Registrant ý

Check the appropriate box:
o   Preliminary Proxy Statement
o   Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
o   Definitive Proxy Statement
o   Definitive Additional Materials
ý   Soliciting Material Pursuant to §240.14a-12

Rational Software Corporation

(Name of Registrant as Specified In Its Charter)

International Business Machines Corporation

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
         
Payment of Filing Fee (Check the appropriate box):
ý   No fee required
o   Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11
    (1)   Title of each class of securities to which transaction applies:
        

    (2)   Aggregate number of securities to which transaction applies:
        

    (3)   Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):
        

    (4)   Proposed maximum aggregate value of transaction:
        

    (5)   Total fee paid:
        

o   Fee paid previously with preliminary materials.
o   Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
    (1)   Amount Previously Paid:
        

    (2)   Form, Schedule or Registration Statement No.:
        

    (3)   Filing Party:
        

    (4)   Date Filed:
        

Filed by International Business Machines Corporation
Pursuant to Rule 14a-12
of the Securities Exchange Act of 1934
Subject Company: Rational Software Corporation
Commission File No.: 000-12167



IBM Software and Rational

Enabling Businesses to Build & Deploy
Infrastructures for the Connected Business

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John A. Swainson
General Manager, Application Integration & Middleware
IBM Software Group


What this news means to you


Key HR points as they relate to you


IBM's Software
Business


Evolving Business Needs

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Today's Enterprise IT Environment

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Value of Common Software Infrastructure

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Software Group Development and Research

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IBM's e-business Strategy

Integrated Demand to Deliver

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IBM's Software Strategy

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Product Positioning within IBM Middleware

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Software Acquisitions

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Shared Capabilities of IBM's Software Portfolio

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WebSphere Portal

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Extending the WebSphere Platform to IBM and Partners

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Rapid Market Acceptance

WebSphere Portal Server

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Software
Group Metrics

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Industry Dynamics

Software Opportunity (2006) = $307B
'02 - '06 CGR = 10%

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Operating Systems

  Middleware
  Applications
$31B   $115B   $161B
6% CGR   9 - 11% CGR   11% CGR

Note: IBM middleware revenue includes IGS transactions
Source: IBM analysis based on Industry Reports / Market Research, 9/02

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Middleware Opportunity

Middleware Opportunity (2006) = $115B
'02 - '06 CGR = 9 - 11%

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Source: IBM analysis based on Industry Reports / Market Research, 9/02

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IBM Software and Middleware Revenue Growth

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Note:    IBM Software & Middleware revenue growth at constant currency
IBM Middleware revenue includes IGS transactions

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IBM Middleware's Unique Competitive Advantages

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IBM and Rational

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IBM's Software Strategy

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        In connection with the merger, Rational has filed preliminary proxy materials and has filed and will file other relevant documents concerning the transaction with the Securities and Exchange Commission (SEC). STOCKHOLDERS OF RATIONAL ARE URGED TO READ THE DEFINITIVE PROXY STATEMENT AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BECAUSE THEY CONTAIN IMPORTANT INFORMATION. Investors and security holders can obtain free copies of the definitive proxy statement and other documents when they become available by contacting Investor Relations, Rational Software Corporation, 18880 Homestead Road, Cupertino, CA 95014 (Telephone: (408) 863-9900). In addition, documents filed with the SEC by Rational are available free of charge at the SEC's web site at www.sec.gov.

        Information regarding the identity of the persons who may, under SEC rules, be deemed to be participants in the solicitation of stockholders of Rational in connection with the transaction, and their interests in the solicitation, is set forth in the preliminary proxy materials that were filed by Rational with the SEC on December 11, 2002.

Forward-Looking Statements

        Except for historical information contained herein, statements contained in this document may constitute 'forward looking statements' within the meaning of the Private Securities Litigation Reform Act of 1995. These statements are neither promises nor guarantees, but involve a number of risks, uncertainties and other factors that could cause actual results to differ materially from those set forth in the forward-looking statements, including, without limitation, the risk that the merger may not be consummated in a timely manner, if at all, risks regarding employee relations and other risks concerning IBM and Rational and their respective operations that are detailed in the periodic filings with the SEC of IBM and Rational, including their most recent filings on Form 10-K and Form 10-Q.





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IBM Software and Rational Enabling Businesses to Build & Deploy Infrastructures for the Connected Business