Exhibit 99.1

TIBCO SOFTWARE GROWS TOTAL REVENUE BY 23% OVER Q4 2009

Full Year Non-GAAP EPS of $0.76 Increases by 38% over 2009

PALO ALTO, Calif., December 21, 2010 – TIBCO Software Inc. (Nasdaq: TIBX) today announced results for its fourth quarter and fiscal year, which ended on November 30, 2010.

Total revenue for the fourth quarter of fiscal 2010 was $241.2 million and net income was $37.5 million, or $0.22 per diluted share. This compares to total revenue of $195.6 million and net income of $31.7 million, or $0.18 per diluted share, as reported for the fourth quarter of fiscal 2009.

On a non-GAAP basis, net income for the fourth quarter of fiscal 2010 was $53.8 million or $0.31 per diluted share, compared with $39.2 million or $0.23 per diluted share for the fourth quarter of fiscal 2009. Non-GAAP operating income for the fourth quarter of fiscal 2010 was $76.2 million, resulting in a non-GAAP operating margin of 32%. This compares to non-GAAP operating income of $58.3 million, or a 30% non-GAAP operating margin in the fourth quarter of fiscal 2009. Non-GAAP results exclude stock-based compensation expense, amortization of acquired intangible assets, acquisition related and other expenses and restructuring activities and assume a non-GAAP effective tax rate of 30% for fiscal 2010 and 32% for fiscal 2009.

“TIBCO turned in an excellent year in 2010 – demonstrating our innovation leadership, broadening our business model, and delivering substantially higher growth and profit to our shareholders,” said Vivek Ranadivé, TIBCO’s chairman and chief executive officer. “As we turn to 2011, we are in an excellent position to benefit from three key trends in enterprise IT: mobility, cloud computing and real-time information. These trends are generating massive amounts of data and increasing IT complexity, which plays to our core strengths of simplifying systems deployment and integration and distilling insight from disparate pools of information.”

Fourth Quarter Fiscal 2010 Highlights

Full Year Fiscal 2010 Highlights

Conference Call Details

TIBCO has scheduled a conference call for 4:30 pm ET / 1:30 pm PT today to discuss its fourth quarter results. The conference call will be hosted by InterCall and may be accessed over the internet at www.tibco.com or via dial-in at 877-293-9114 or 706-758-2055. Please join the conference call at least 10 minutes early to register. A replay of the conference call will be available until midnight PT on January 21, 2011 at www.tibco.com or via dial-in at 800-642-1687 or 706-645-9291. The pass code for both the call and the replay is 29493957.

About TIBCO

TIBCO Software Inc. (NASDAQ: TIBX) is a provider of infrastructure software for companies to use on-premise or as part of cloud computing environments. Whether it’s optimizing claims, processing trades, cross-selling products based on real-time customer behavior, or averting a crisis before it happens, TIBCO provides companies the two-second advantage^TM – the ability to capture the right information at the right time and act on it preemptively for a competitive advantage. More than 4,000 customers worldwide rely on TIBCO to manage information, decisions, processes and applications in real time. Learn more at www.tibco.com.

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TIBCO, The Power of Now, the two-second advantage, and TIBCO Software are trademarks or registered trademarks of TIBCO Software Inc. in the United States and/or other countries. All other product and company names and marks mentioned in this document are the property of their respective owners and are mentioned for identification purposes only.

About Non-GAAP Financial Information

This press release includes non-GAAP financial measures. For a description of these non-GAAP financial measures, including the reasons management uses each measure, and reconciliations of these non-GAAP financial measures to the most directly comparable financial measures prepared in accordance with Generally Accepted Accounting Principles (GAAP), please see the section entitled “About Non-GAAP Financial Measures” and the accompanying table entitled “Reconciliation of GAAP to Non-GAAP Measures.”

Legal Notice Regarding Forward-Looking Statements

This release contains forward-looking statements within the meaning of the “safe harbor” provisions of the federal securities laws. The final financial results for fourth quarter of fiscal year 2010 may differ materially from the preliminary results presented in this release due to factors that include, but are not limited to, risks associated with the final review of the results and preparation of financial statements. In addition, forward-looking statements such as statements regarding the ability of TIBCO to benefit from three key trends in enterprise IT: mobility, cloud computing and real-time information are subject to risks and uncertainties that could cause actual results to differ materially from such forward-looking statements. These risks include but are not limited to: our ability to adapt to new technologies and evolving industry trends; and competitive factors, including but not limited to competition from alternative business models, industry consolidation and new product introductions. Additional information regarding potential risks is provided in TIBCO’s filings with the SEC, including its most recent Annual Report on Form 10-K for the year ended November 30, 2009 and Quarterly Report on Form 10-Q for the quarter ended August 29, 2010. TIBCO assumes no obligation to update the forward-looking statements included in this release.

TIBCO Software Inc.

Condensed Consolidated Balance Sheets

(unaudited)

(in thousands)

TIBCO Software Inc.

Condensed Consolidated Statements of Operations

(unaudited)

(in thousands, except net income per share)

TIBCO Software Inc.

Condensed Consolidated Statements of Cash Flows

(unaudited)

(in thousands)

About Non-GAAP Financial Measures

TIBCO provides non-GAAP measures for operating income, net income and net income per share data as supplemental information regarding TIBCO’s business performance. TIBCO believes that these non-GAAP financial measures are useful to investors because they exclude non-operating charges. TIBCO’s management excludes these non-operating charges when it internally evaluates the performance of TIBCO’s business and makes operating decisions, including internal budgeting, performance measurement and the calculation of bonuses and discretionary compensation, because these measures provide a consistent method of comparison to historical periods. Moreover, management believes these non-GAAP measures reflect the essential revenue generation activities of TIBCO. Accordingly, management excludes stock-based compensation related to employee stock options, amortization of acquired intangible assets, costs related to formal restructuring activities, acquisition-related and other expenses, gains and losses on equity investments, and the income tax effects of the foregoing, as well as adjustments for the impact of changes in the valuation allowance recorded against TIBCO’s deferred tax assets when making operational decisions.

TIBCO believes that providing the non-GAAP measures that management uses to its investors is useful to investors for a number of reasons. The non-GAAP measures provide a consistent basis for investors to understand TIBCO’s financial performance on a trended basis across historical periods. In addition, it allows investors to evaluate TIBCO’s performance using the same methodology and information as that used by TIBCO’s management.

Non-GAAP measures are subject to material limitations as these measures are not in accordance with, or a substitute for, GAAP and thus TIBCO’s definition may be different from similar non-GAAP measures used by other companies and/or analysts. However, TIBCO’s management compensates for these limitations by providing the relevant disclosure of the items excluded in the calculation of non-GAAP operating income, non-GAAP net income and non-GAAP net income per share. In addition, some items such as restructuring charges that are excluded from non-GAAP net income and non-GAAP earnings per share can have a material impact on cash flows and stock compensation charges can have a significant impact on earnings. Management compensates for these limitations by evaluating the non-GAAP measure together with the most directly comparable GAAP measure. TIBCO has historically provided non-GAAP measures to the investment community as a supplement to its GAAP results, to enable investors to evaluate TIBCO’s business performance in the way that management does.

The non-GAAP adjustments, and the basis for excluding them, are outlined below:

Amortization of Intangible Assets

TIBCO has incurred amortization of intangible assets, included in its GAAP financial statements, related to various acquisitions TIBCO has made. Management excludes these items, for the purposes of calculating non-GAAP operating income, non-GAAP net income and non-GAAP net income per share. TIBCO believes that eliminating this expense from its non-GAAP measures is useful to investors, because the amortization of intangible assets can be inconsistent in amount and frequency and is significantly impacted by the timing and magnitude of TIBCO’s acquisition transactions, which also vary substantially in frequency from period to period.

Stock-based Compensation

TIBCO incurs stock-based compensation expense. TIBCO excludes this item for the purposes of calculating non-GAAP operating income, non-GAAP net income and non-GAAP net income per share because it is a non-cash expense that TIBCO believes is not reflective of its business performance. The nature of the stock-based compensation expense also makes it very difficult to estimate prospectively, since the expense will vary with changes in the stock price and market conditions at the time of new grants, varying valuation methodologies, subjective assumptions and different award types, making the comparison of current results with forward-looking guidance potentially difficult for investors to interpret. The tax effects of stock-based compensation expenses may also vary significantly from period to period, without any change in underlying operational performance, thereby obscuring the underlying profitability of operations relative to prior periods. Finally,

TIBCO believes that non-GAAP measures of profitability that exclude stock-based compensation are widely used by analysts and investors in the software industry.

Acquisition-related and Other Expenses

TIBCO has incurred acquisition-related and other expenses which consist of costs incurred after the issuance of a definitive term sheet for a particular transaction (whether or not such transaction is ultimately completed, remains in process or is not completed) and include legal, banker, accounting and other advisory fees of third parties and severance costs for employees of the acquired company that are terminated within 90 days of the acquisition date. Management excludes these items, for the purposes of calculating non-GAAP operating income, non-GAAP net income and non-GAAP net income per share. TIBCO believes that eliminating these expenses from its non-GAAP measures is useful to investors, because it generally would not have otherwise incurred such expenses in the periods presented as part of its continuing operations. The acquisition-related and other expenses are not recurring with respect to past transactions, can be inconsistent in amount and frequency from period to period and are significantly impacted by the timing and magnitude of TIBCO’s acquisitions. While these expenses are not recurring with respect to past transactions, TIBCO generally will incur these expenses in connection with any future acquisitions.

Restructuring Activities

TIBCO has incurred restructuring expenses, included in its GAAP presentation of operating expense, primarily due to workforce related charges such as payments for severance and benefits and estimated costs of exiting and terminating facility lease commitments related to a formal restructuring plan. TIBCO excludes these items, for the purposes of calculating non-GAAP operating income, non-GAAP net income and non-GAAP net income per share, when it evaluates the continuing business performance of TIBCO. TIBCO believes that these items are not consistently recurring and do not necessarily reflect expected future operating expense, nor does TIBCO believe that they provide a meaningful evaluation of current versus past business results or the expense levels required to support TIBCO’s operating plan.

TIBCO Software Inc.

Reconciliation of GAAP to Non-GAAP Measures

(unaudited)

(in thousands, except net income per share)