SCHEDULE 14A

(RULE 14a-101)

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.      )

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¨ Preliminary Proxy Statement

¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

¨ Definitive Proxy Statement

¨ Definitive Additional Materials

x  Soliciting Material Pursuant to §240.14a-12

MARIMBA, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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¨ 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.

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Filed by Marimba, Inc.

Pursuant to Rule 14a-12

Under the Securities Exchange Act of 1934

Subject Company: Marimba, Inc.

Commission File No.: 000-25683

This filing relates to the acquisition of Marimba, Inc. by BMC Software, Inc. pursuant to an Agreement and Plan of Merger, dated as of April 28, 2004.

On April 29, 2004, BMC Software posted the following presentation slides on its website, www.bmc.com, related to BMC Software’s acquisition of Marimba.

BMC Software to Acquire Marimba

Expanded Change and Configuration

Management Capabilities to

Extend BSM Strategy

Forward-Looking Statements

This presentation contains forward-looking statements that involve risks and uncertainties concerning BMC Software’s proposed acquisition of Marimba, BMC Software’s expected financial performance, as well as BMC Software’s strategic and operational plans. Forward-looking statements made about the business, strategic and operational plans or financial performance of BMC Software are made solely by BMC Software Inc., and Marimba, Inc. undertakes no responsibility or liability for such statements. Actual events or results may differ materially from those described in this presentation due to a number of risks and uncertainties. Potential risks and uncertainties regarding the acquisition include, among others, the requirement that Marimba’s stockholders must approve the transaction, the required receipt of necessary regulatory approvals, including from the SEC and under applicable antitrust laws, other conditions to the closing of the merger, the possibility that the transaction will not close or that the closing may be delayed, and the effect of the announcement of the merger on Marimba’s customer relationships, operating results and business generally, including the ability to retain key employees. Other potential risks and uncertainties include, among others, the reaction of customers of BMC Software and Marimba to the transaction; BMC Software’s ability to successfully integrate Marimba’s operations and employees; and general economic conditions. More information about potential factors that could affect BMC Software’s business and financial results is included in BMC Software’s SEC filings. For more information and additional risk factors regarding Marimba, see Marimba’s SEC filings. All SEC filings are available at www.sec.gov.

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Transaction Overview

BMC Software has signed a definitive merger agreement to acquire Marimba for $8.25 per share in cash

Transaction reflects a net price of approximately $187 million, adjusted for Malta’s expected net cash balance, as of March 31, 2004

Expected to be accretive to earnings within 12 months of closing

Marimba business will be an important extension of BSM capabilities as this acquisition unites key technology processes to provide a more complete answer to BMC customers’ change process and configuration management problems

The acquisition is subject to regulatory and Marimba shareholder approval, currently anticipated to be during BMC’s second fiscal quarter

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Marimba Overview

Marimba is a systems management software company, specifically focused on change and configuration management

Nasdaq: MRBA, founded in 1996, public in 1999

Headquarters: Mountain View, California

Trailing twelve month revenues of $38.9 million as of March 31, 2004

Over $52.9 million in cash, no debt

Approximately 170 employees

200+ customers comprising Fortune 50 and Global 1000 organizations

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Why Marimba?

Leading technology

Policy-based management paradigm: Set the rules once, the software does the work Transport is more secure, more scalable

Flexible architecture lets Marimba rapidly develop products in response to changing IT landscape

Heterogeneity –enables comprehensive support across heterogeneous environments including Windows, Linux, AIX, HP-UX, Solaris and fits with BMC platform agnostic philosophy

Modularity – solutions address specific customer need for discrete projects

Breadth of offering is strong complement to BMC’s BSM solution

Core technology addresses many problems – security patch management, asset discovery, server management, license compliance, OS management, software distribution

Solution focus on business/IT alignment problems

Immediate ROI – reduce customer costs and business risk

World-class customer base

Blue-chip global customer base with strong repeat business

Technology “battle tested” with enterprise customers

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Marketplace synergies with Remedy

Combining Marimba with BMC extends the longstanding relationship between Marimba and BMC and Remedy and creates substantial marketplace synergies

Complements and extends BMC’s server management offering by providing Marimba’s cross-platform change and configuration management capabilities for servers in datacenters and remote offices

Adds client systems management capabilities to the most complete IT Service Management solution available for asset management, change management, and service desks

Advances the asset configuration and inventory management capabilities of our combined customer base as they pursue strategies to align business objectives with IT investments

Enables customers to better manage the requirements of IT change and configuration management within a distributed network

Provides customers an integrated approach to change, asset, and discovery solutions

The combined Marimba/BMC solution enables customers to:

Improve control of their IT infrastructure through automated inventory of hardware and software configurations

Manage software performance through automated distribution of patches and upgrades

Track software license usage data to accurately size purchase requirements and prevent overbuying

Significantly reduce BSM implementation time through auto-discovery to populate the business service impact model

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Marimba Products and Services Overview

Marimba gives customers dynamic control of IT resources by offering completechange & configuration management solutions for both client & server environments

Marimba’s Client Management products automate the deployment and management of applications, deployment of updates and patches, migration to new operating systems, inventory scans & software usage tracking across desktops, laptops & mobile devices

Marimba’s Server Management products automate critical server management functions such as inventory, provisioning, packaging, configuration, auditing and repair, reducing the complexity of managing servers across the enterprise

Marimba solutions address some of the most important IT business problems such as:

Asset Discovery

Security Patch Management

Software Distribution

Software License Compliance

Server Management

Operating Systems Management

IT Asset Tracking and Management

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Additional Information About the Merger and Where to Find It

Marimba will file a proxy statement and other documents regarding the proposed merger described in this press release with the SEC. MARIMBA STOCKHOLDERS ARE URGED TO READ THE PROXY STATEMENT WHEN IT BECOMES AVAILABLE, BECAUSE IT WILL CONTAIN IMPORTANT INFORMATION. A definitive proxy statement will be sent to stockholders of Marimba seeking their approval of the transaction. Investors and security holders may obtain a copy of the proxy statement (when it is available) and any other relevant documents filed by Marimba with the SEC for free at the SEC’s web site at www.sec.gov. Copies of the proxy statement and other documents filed by Marimba with the SEC may also be obtained free of cost by directing a request to: Investor Relations Group, Marimba, Inc, 440 Clyde Avenue, Mountain View, CA 94043; or InvestorRelations@marimba.com. You may also read and copy any reports, statements and other information filed by Marimba at the SEC public reference rooms at 450 Fifth Street, N.W., Washington, D.C. 20549 or at the SEC’s other public reference rooms in New York, New York and Chicago, Illinois. Please call the SEC at 1-800-SEC-0330 for further information on public reference rooms.

Marimba and BMC Software and their respective directors, executive officers and certain of their employees may be deemed to be participants in the solicitation of proxies of Marimba stockholders in connection with the proposed merger. Certain directors and executive officers of Marimba may have interests in the merger, including severance arrangements, acceleration of vesting of stock options and as a result of holding options or shares of Marimba common stock generally, and their interests will be described in the proxy statement that will be filed by Marimba with the SEC.