content: <PAGE>
  
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                         SECURITIES AND EXCHANGE COMMISSION
  
                               Washington, DC  20549
  
                                --------------------
                                      FORM 8-K
  
  
                                   CURRENT REPORT
                       PURSUANT TO SECTION 13 OR 15(d) OF THE
                          SECURITIES EXCHANGE ACT OF 1934
  
                                --------------------
  
  
  
  Date of Report (Date of earliest event reported):    May 25, 1999
  
  
  
  
                            CADENCE DESIGN SYSTEMS, INC.
                (Exact Name of Registrant as Specified in  Charter)
  
  
  
  
             Delaware                 1-10606                  77-0148231
    (State or Other Jurisdiction    (Commission File        (I.R.S. Employer
        of Incorporation )              Number)           Identification Number)
  
  
                            2655 Seely Road, Building 5
                            San Jose, California 95134
                        (Address of Principal Executive Offices)(Zip Code)
  
  
  Registrant's telephone number, including area code:    (408) 943-1234
  
  
  
  ================================================================================
  <PAGE>
  
  Item 2.    Acquisition or Disposition of Assets.
  -------    -------------------------------------
  
       On May 25, 1999, Cadence Design Systems, Inc., a Delaware corporation (the
  "Registrant"), acquired all of the outstanding capital stock of Quickturn Design
  Systems, Inc., a Delaware corporation ("Quickturn"), for an aggregate purchase
  price of $271 million (the "Acquisition").  Quickturn stockholders will receive
  the Registrant's common stock at an exchange ratio of 1.2712 of the Registrant's
  shares for each share of Quickturn common stock.  The Acquisition was effected
  by means of a merger pursuant to which a wholly-owned subsidiary of the
  Registrant merged with and into Quickturn, with Quickturn as the surviving
  company.  As a result of such merger, Quickturn became a wholly-owned subsidiary
  of the Registrant.  The consideration paid by the Registrant for Quickturn's
  outstanding capital stock was negotiated at arm's length between the parties on
  the basis of the Registrant's assessment of the value of Quickturn and its
  capital stock, following an investigation of, and discussions with Quickturn and
  its representatives concerning Quickturn and its business and prospects.
  Certain of Quickturn's officers, including Keith R. Lobo, President and Chief
  Executive Officer of Quickturn, have entered into employment and related
  agreements with the Registrant.  To the Registrant's knowledge, there is no
  other material relationship between any of the former stockholders of Quickturn
  and the Registrant or any of its affiliates, any director or officer of the
  Registrant, or any associate of any such director or officer.
  
  Item 7.    Financial Statements, Pro Forma Financial Information and Exhibits.
  -------    -------------------------------------------------------------------
  
  (a)  Financial Statements of Business Acquired
  
       None of the required financial statements are currently available.
  Pursuant to paragraph (a)(4) of Item 7, the required financial statements will
  be filed as soon as practicable, but not later than July 26, 1999, unless
  waived.
  
  (b)  Pro Forma Financial Information
  
       None of the required pro forma financial information is currently
  available.  Pursuant to paragraph (b)(2) of Item 7, the required pro forma
  financial information will be filed as soon as practicable, but not later than
  July 26, 1999, unless waived.
  
  (c)  Exhibits
  
       Exhibit No.        Description
       -----------        -----------
  
       Exhibit 99.1       Press Release of the Registrant issued on May 25, 1999.
  <PAGE>
  
                                     SIGNATURES
  
       Pursuant to the requirements of the Securities Exchange Act of 1934, the
  Registrant has duly caused this report to be signed on its behalf by the
  undersigned hereunto duly authorized.
  
  Dated as of May 25, 1999.
  
                                     CADENCE DESIGN SYSTEMS, INC.
  
                                     By:  /s/  R.L. Smith McKeithen
                                         ---------------------------
                                         R.L. Smith McKeithen
                                         Senior Vice President and General Counsel
  <PAGE>
  
                                   EXHIBIT INDEX
                                                                      Sequentially
                                                                        Numbered
  Exhibit No.  Document                                                   Page
  ------------ ------------------------------------------------------ ------------
  Exhibit 99.1 Press Release of the Registrant issued on May 25, 1999.
metadata_documents: [{"type": "8-K", "sequence": "1", "description": "FORM 8-K", "secsgml_size_bytes": 4879}]
metadata_filer: {"company-data": {"conformed-name": "CADENCE DESIGN SYSTEMS INC", "cik": "0000813672", "assigned-sic": "7372", "irs-number": "770148231", "state-of-incorporation": "DE", "fiscal-year-end": "0102"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-10606", "film-number": "99634951"}, "business-address": {"street1": "2655 SEELY ROAD BLDG 5", "city": "SAN JOSE", "state": "CA", "zip": "95134", "phone": "4089431234"}, "mail-address": {"street1": "555 RIVER OAKS PARKWAY", "city": "SAN JOSE", "state": "CA", "zip": "95134"}, "former-company": {"former-conformed-name": "ECAD INC /DE/", "date-changed": "19880609"}}
text: ================================================================================
  
                         SECURITIES AND EXCHANGE COMMISSION
  
                               Washington, DC  20549
  
                                --------------------
                                      FORM 8-K
  
                                   CURRENT REPORT
                       PURSUANT TO SECTION 13 OR 15(d) OF THE
                          SECURITIES EXCHANGE ACT OF 1934
  
                                --------------------
  
  Date of Report (Date of earliest event reported):    May 25, 1999
  
                            CADENCE DESIGN SYSTEMS, INC.
                (Exact Name of Registrant as Specified in  Charter)
  
             Delaware                 1-10606                  77-0148231
    (State or Other Jurisdiction    (Commission File        (I.R.S. Employer
        of Incorporation )              Number)           Identification Number)
  
                            2655 Seely Road, Building 5
                            San Jose, California 95134
                        (Address of Principal Executive Offices)(Zip Code)
  
  Registrant's telephone number, including area code:    (408) 943-1234
  
  ================================================================================
  Item 2.    Acquisition or Disposition of Assets.
  -------    -------------------------------------
  
       On May 25, 1999, Cadence Design Systems, Inc., a Delaware corporation (the
  "Registrant"), acquired all of the outstanding capital stock of Quickturn Design
  Systems, Inc., a Delaware corporation ("Quickturn"), for an aggregate purchase
  price of $271 million (the "Acquisition").  Quickturn stockholders will receive
  the Registrant's common stock at an exchange ratio of 1.2712 of the Registrant's
  shares for each share of Quickturn common stock.  The Acquisition was effected
  by means of a merger pursuant to which a wholly-owned subsidiary of the
  Registrant merged with and into Quickturn, with Quickturn as the surviving
  company.  As a result of such merger, Quickturn became a wholly-owned subsidiary
  of the Registrant.  The consideration paid by the Registrant for Quickturn's
  outstanding capital stock was negotiated at arm's length between the parties on
  the basis of the Registrant's assessment of the value of Quickturn and its
  capital stock, following an investigation of, and discussions with Quickturn and
  its representatives concerning Quickturn and its business and prospects.
  Certain of Quickturn's officers, including Keith R. Lobo, President and Chief
  Executive Officer of Quickturn, have entered into employment and related
  agreements with the Registrant.  To the Registrant's knowledge, there is no
  other material relationship between any of the former stockholders of Quickturn
  and the Registrant or any of its affiliates, any director or officer of the
  Registrant, or any associate of any such director or officer.
  
  Item 7.    Financial Statements, Pro Forma Financial Information and Exhibits.
  -------    -------------------------------------------------------------------
  
  (a)  Financial Statements of Business Acquired
  
       None of the required financial statements are currently available.
  Pursuant to paragraph (a)(4) of Item 7, the required financial statements will
  be filed as soon as practicable, but not later than July 26, 1999, unless
  waived.
  
  (b)  Pro Forma Financial Information
  
       None of the required pro forma financial information is currently
  available.  Pursuant to paragraph (b)(2) of Item 7, the required pro forma
  financial information will be filed as soon as practicable, but not later than
  July 26, 1999, unless waived.
  
  (c)  Exhibits
  
       Exhibit No.        Description
       -----------        -----------
  
       Exhibit 99.1       Press Release of the Registrant issued on May 25, 1999.
  SIGNATURES
  
       Pursuant to the requirements of the Securities Exchange Act of 1934, the
  Registrant has duly caused this report to be signed on its behalf by the
  undersigned hereunto duly authorized.
  
  Dated as of May 25, 1999.
  
                                     CADENCE DESIGN SYSTEMS, INC.
  
                                     By:  /s/  R.L. Smith McKeithen
                                         ---------------------------
                                         R.L. Smith McKeithen
                                         Senior Vice President and General Counsel
  EXHIBIT INDEX
                                                                      Sequentially
                                                                        Numbered
  Exhibit No.  Document                                                   Page
  ------------ ------------------------------------------------------ ------------
  Exhibit 99.1 Press Release of the Registrant issued on May 25, 1999.