Exhibit 99.1

PRESS RELEASE

INVESTOR CONTACT:

Lisa L. Ewbank

Synopsys, Inc.

650-584-1901

EDITORIAL CONTACT:

Yvette Huygen

Synopsys, Inc.

650-584-4547

yvetteh@synopsys.com

Synopsys Posts Financial Results for Fourth Quarter and Fiscal Year 2012

Q4 2012 Financial Highlights

FY 2012 Financial Highlights

MOUNTAIN VIEW, Calif. – Dec. 5, 2012 – Synopsys, Inc. (Nasdaq: SNPS), a global leader providing software, IP and services used to accelerate innovation in chips and electronic systems, today reported results for its fourth quarter and fiscal year 2012.

For the fourth quarter of fiscal 2012, Synopsys reported revenue of $454.2 million, compared to $390.5 million for the fourth quarter of fiscal 2011. Revenue for fiscal year 2012 was $1.756 billion, an increase of 14.3 percent from $1.536 billion in fiscal 2011.

“Synopsys delivered very strong fiscal 2012 results with double-digit revenue and non-GAAP earnings per share growth. Simultaneously we also completed a significant number of important acquisitions during the year,” said Aart de Geus, chairman and co-CEO of Synopsys. “Electronic design automation solutions are more critical than ever, as semiconductor companies face significant technical challenges while racing to design highly complex chips and systems. Synopsys is particularly well-positioned heading into 2013, based on our technology leadership, significant customer demand, and our predictable business model.”

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GAAP Results

On a generally accepted accounting principles (GAAP) basis, net income for the fourth quarter of fiscal 2012 was $29.1 million, or $0.19 per share, compared to $39.9 million, or $0.27 per share, for the fourth quarter of fiscal 2011. GAAP net income for fiscal year 2012 was $182.4 million, or $1.21 per share, compared to $221.4 million, or $1.47 per share, for fiscal 2011. Net income for fiscal 2012 included $43.6 million of acquisition-related costs, plus higher amortization of intangibles than in the previous year primarily due to acquisitions. Due to our fiscal calendar, the first quarter of fiscal year 2012 included an extra week.

Non-GAAP Results

On a non-GAAP basis, net income for the fourth quarter of fiscal 2012 was $72.4 million, or $0.47 per share, compared to non-GAAP net income of $65.3 million, or $0.45 per share, for the fourth quarter of fiscal 2011. Non-GAAP net income for fiscal 2012 was $315.5 million, or $2.10 per share, compared to non-GAAP net income of $270.3 million, or $1.80 per share, for fiscal 2011. Reconciliation between GAAP and non-GAAP results is provided at the end of this press release. Due to our fiscal calendar, the first quarter of fiscal year 2012 included an extra week.

Financial Targets

Synopsys also provided its financial targets for the first quarter and full fiscal year 2013. These targets do not include any impact of future acquisition-related activities. These targets constitute forward-looking information and are based on current expectations. For a discussion of factors that could cause actual results to differ materially from these targets, see “Forward-Looking Statements” below.

First Quarter of Fiscal Year 2013 Targets:

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Full Fiscal Year 2013 Targets:

GAAP Reconciliation

Synopsys continues to provide all information required in accordance with GAAP but believes evaluating its ongoing operating results may not be as useful if an investor is limited to reviewing only GAAP financial measures. Accordingly, Synopsys presents non-GAAP financial measures in reporting its financial results to provide investors with an additional tool to evaluate Synopsys’ operating results in a manner that focuses on what Synopsys believes to be its ongoing business operations and what Synopsys uses to evaluate its ongoing operations and for internal planning and forecasting purposes. Synopsys’ management does not itself, nor does it suggest that investors should, consider such non-GAAP financial measures in isolation from, or as a substitute for, financial information prepared in accordance with GAAP. Synopsys’ management believes it is useful for itself and investors to review, as applicable, both GAAP information that includes: (i) the amortization of acquired intangible assets, (ii) the impact of stock compensation, (iii) acquisition-related costs, including inventory fair value adjustments, (iv) other significant items, including facilities restructuring charges and the effect of benefits from tax settlements with tax authorities, and (v) the income tax effect of non-GAAP pre-tax adjustments as well as unusual or infrequent tax adjustments; and the non-GAAP measures that exclude such information in order to assess the performance of Synopsys’ business and for planning and forecasting in subsequent periods. Whenever Synopsys uses a non-GAAP financial measure, it provides a reconciliation of the non-GAAP financial measure to the most closely applicable GAAP financial measure. Investors are encouraged to review the related GAAP financial measures and the reconciliation of these non-GAAP financial measures to their most directly comparable GAAP financial measure as detailed below.

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Reconciliation of Fourth Quarter and Fiscal Year 2012 Results

The following tables reconcile the specific items excluded from GAAP in the calculation of non-GAAP net income and earnings per share for the periods indicated below.

GAAP to Non-GAAP Reconciliation of Fourth Quarter and Fiscal Year 2012 Results

(Unaudited and in thousands, except per share amounts)

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Reconciliation of Target Non-GAAP Operating Results

The following tables reconcile the specific items excluded from GAAP in the calculation of target non-GAAP operating results for the periods indicated below.

GAAP to Non-GAAP Reconciliation of First Quarter Fiscal Year 2013 Targets

(in thousands, except per share amounts)

GAAP to Non-GAAP Reconciliation of Full Fiscal Year 2013 Targets

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Earnings Call Open to Investors

Synopsys will hold a conference call for financial analysts and investors today at 2:00 p.m. Pacific Time. A live webcast of the call will be available at Synopsys’ corporate website at www.synopsys.com. A recording of the call will be available by calling +1-800-475-6701 (+1-320-365-3844 for international callers), access code 271818 beginning at 4:00 p.m. Pacific Time today. A webcast replay will also be available on the website from approximately 5:30 p.m. Pacific Time today through the time Synopsys announces its results for the first quarter fiscal 2013 in February 2013. Synopsys will post copies of the prepared remarks of Aart de Geus, chairman and co-chief executive officer, and Brian Beattie, chief financial officer, on its website following the call. In addition, Synopsys makes additional financial information available in a financial supplement also posted on the corporate website.

Effectiveness of Information

The targets included in this release, the statements made during the earnings conference call and the information contained in the financial supplement (available in the Investor Relations section of Synopsys’ website at www.synopsys.com) represent Synopsys’ expectations and beliefs as of the date of this release only. Although this press release, copies of the prepared remarks of the co-chief executive officer and chief financial officer made during the call and the financial supplement will remain available on Synopsys’ website through the date of the first quarter fiscal year 2013 earnings call in February 2013, their continued availability through such date does not mean that Synopsys is reaffirming or confirming their continued validity. Synopsys does not currently intend to report on its progress during the first quarter of fiscal 2013 or comment to analysts or investors on, or otherwise update, the targets given in this earnings release.

Availability of Final Financial Statements

Synopsys will include final financial statements for the fourth quarter and fiscal 2012 in its annual report on Form 10-K to be filed by January 2, 2013.

About Synopsys

Synopsys, Inc. (Nasdaq:SNPS) accelerates innovation in the global electronics market. As a leader in electronic design automation (EDA) and semiconductor IP, its software, IP and services help engineers address their design, verification, system and manufacturing challenges. Since 1986, engineers around the world have been using Synopsys technology to design and create billions of chips and systems. Learn more at http://www.synopsys.com.

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Forward-Looking Statements

The statements made in this press release regarding projected financial results in the sections entitled “Financial Targets,” and “Reconciliation of Target Non-GAAP Operating Results,” and certain other statements, including statements regarding customer demand for our technology and predictable business model, are forward-looking statements within the meaning of the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934. In addition, certain statements made in the earnings conference call are forward-looking statements within the meaning of the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934. Actual results could differ materially from those described by these statements due to a number of uncertainties, including, but not limited to:

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In addition, Synopsys’ actual expenses, earnings per share and tax rate on a GAAP and non-GAAP basis for the fiscal quarter ending January 31, 2013; actual expenses, earnings per share, tax rate, and other projections on a GAAP and non-GAAP basis for fiscal year 2013; and cash flow from operations on a GAAP basis for fiscal year 2013 could differ materially from the targets stated under “Financial Targets” above for a number of reasons, including, but not limited to, (i) integration and other acquisition-related costs, (ii) application of the actual consolidated GAAP and non-GAAP tax rates for such periods, or judgment by management, based upon the status of pending audits and settlements to increase or decrease an income tax asset or liability, (iii) a determination by Synopsys that any portion of its goodwill or intangible assets have become impaired, (iv) changes in the anticipated amount of employee stock-based compensation expense recognized on Synopsys’ financial statements, (v) actual change in the fair value of Synopsys’ non-qualified deferred compensation plan obligations, (vi) increases or decreases to estimated capital expenditures, (vii) changes driven by new accounting rules, regulations, interpretations or guidance, (viii) general economic conditions, and (ix) other risks as detailed in Synopsys’ SEC filings, including those described in the “Risk Factors” section in its latest Quarterly Report on Form 10-Q for the third quarter ended July 31, 2012. Furthermore, Synopsys’ actual tax rates applied to income for the first quarter and fiscal year 2013 could differ from the targets given in this press release as a result of a number of factors, including the actual geographic mix of revenue during the quarter and year, and actions by the government.

Finally, Synopsys’ targets for outstanding shares in the first quarter and fiscal year 2013 could differ from the targets given in this press release as a result of higher than expected employee stock plan issuances or stock option exercises, acquisitions, and the extent of Synopsys’ stock repurchase activity.

Synopsys is under no obligation to (and expressly disclaims any such obligation to) update or alter any of the forward-looking statements made in this earnings release, the conference call or the financial supplement whether as a result of new information, future events or otherwise, unless otherwise required by law.

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SYNOPSYS, INC.

Unaudited Consolidated Statements of Operations (1)

(in thousands, except per share amounts)

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SYNOPSYS, INC.

Unaudited Consolidated Balance Sheets (1)

(in thousands, except par value amounts)

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SYNOPSYS, INC.

Unaudited Consolidated Statements of Cash Flows (1)

(in thousands)

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