Douglas N. Cogen

Co-Chair, Mergers & Acquisitions

Partner, Corporate  

San Francisco 415.875.2409


Doug advises technology and life sciences clients on mergers and acquisitions, strategic and commercial transactions, corporate counseling and governance, securities matters, shareholder activism and takeover defense. He co-chairs Fenwick’s M&A practice and served as a member of the firm’s executive committee for 10 years.

Doug's transactional experience includes over $150 billion of completed mergers, acquisitions and divestitures including cross-border transactions in the software, cybersecurity, internet, life sciences, medical devices, telecommunications, networking, semiconductor, computer hardware and consumer products industries.

Doug is ranked by Chambers Global as among the world’s leading lawyers for U.S. Corporate/M&A and is recognized as a Notable Practitioner for Corporate/M&A in the Nationwide–Highly Regarded listings. The publication, which includes client testimonials, recognized him as:​

  • "Incredibly smart and a consummate professional" and "he's tremendously strategic and knows how to leverage his experience" (2020)
  • “Fantastic,” helps clients “understand the legal aspect of a matter without the jargon” (2019)
  • “An excellent ​lawy​er, partner and advisor, highly respected by company executives and board members” (2018)
  • “Incredibly balanced” (2017)
  • A “strategically brilliant practitioner who understands public M&A” (2016)
  • Uses “innovative, outside-the-box solutions” (2014)
  • “An incredible negotiator who sees the big picture” and “fair and easy to deal with” (2013)

Representative Experience

Representative Technology Transactions

  • Over 125 deals for Cisco Systems, including the acquisitions of:
    • Scientific-Atlanta for $6.9 billion
    • NDS Group for $5 billion
    • AppDynamics for $3.7 billion​
    • WebEx Communications for $3.2 billion
    • Starent Networks for $2.9 billion
    • Sourcefire for $2.7 billion
    • Duo Security for $2.3 billion
    • BroadSoft for $1.9 billion
  • Multiple deals for Symantec, including:
    • Sale of its Enterprise Security business to Broadcom for $10.7 billion
    • ​Sale of the Veritas information management business to The Carlyle Group for $7.4 billion
    • Merger with Blue Coat for $4.65 billion
    • Acquisition of LifeLock for $2.3 billion
    • Sale of the website security solutions business to DigiCert for ~$1 billion
  • VeriSign's $21 billion merger with Network Solutions
  • Concur’s $8.3 billion acquisition by SAP
  • GitHub's $7.5 billion acquisition by Microsoft
  • Excite's $7.2 billion merger with @Home Corporation
  • NetScreen Technologies' $4.3 billion merger with Juniper Networks
  • Macromedia's $3.4 billion merger with Adobe Systems
  • Fitbit's pending $2.1 billion acquisition by Google
  • ArcSight’s $1.5 billion acquisition by Hewlett-Packard
  • Elantec Semiconductor's $1.4 billion acquisition by Intersil Corporation

Representative Life Sciences Transactions

  • Loxo Oncology’s $8 billion acquisition by Eli Lilly
  • Cepheid’s $4 billion acquisition by Danaher Corporation​
  • Audentes Therapeutics’ $3 billion acquisition by Astellas Pharma
  • Agilent Technologies’ $1.5 billion acquisition of Varian
  • Dermira’s $1.1 billion acquisition by Eli Lilly​
  • Connetics' $930 million merger with Stiefel Laboratories


  • Chambers ranked Doug as a leading lawyer for U.S. Corporate/M&A law (multiple years from 2006 – 2020)
  • Law360 named Doug “Tech MVP of the Year” (2019)
  • The Deal named him “Lawyer of the Year” for technology and telecom dealmaking (2018)
  • The Daily Journal thrice ranked him as one of the Top 100 Attorneys in California (2006, 2013, 2018)
  • The Legal 500 recognized Doug in its "Hall of Fame" (2018 – 2019) and as a leading lawyer for “United States - M&A/Corporate” (2014 – 2019)
  • Finance Monthly twice named Doug “Deal Maker of the Year” (2015, 2017)
  • Global M&A Network named him one of the top 50 Global M&A Lawyers (2014), and recognized him as M&A Lawyer of the Year (2010)
  • Who’s Who Legal ranked Doug for M&A (2014 – 2019) and Corporate Governance (2018 – 2019)
  • IFLR1000 recognized him as an “Elite Dealmaker” (2018)
  • Best Lawyers recognized Doug as one of the “Best Lawyers in America” for M&A law (2011 – 2019)
  • Super Lawyers ranked him as a Northern California “Super Lawyer” (2006 – 2020)

Doug has served as director of Intergovernmental Relations for the New York City Planning Commission. He has also lectured on transactional law at Columbia University Law School, Stanford University Law School and the Stanford Graduate School of Business.​​​​​​​​​​​​​​