Sydney Gaylin represents private and public companies in corporate and securities law matters, including mergers and acquisitions and other transactions. She also advises on securities law compliance, corporate governance and other general corporate matters.

Ms. Gaylin’s representations include:

  • Goldman Sachs and Centerview Partners as financial advisors to Momenta Pharmaceuticals in its pending $6.5 billion sale to Johnson & Johnson;
  • Stemline Therapeutics in its $677 million-valued sale to Menarini Group;
  • Gilead Sciences in its $4.9 billion acquisition of Forty Seven;
  • Carbonite in its $1.42 billion sale to OpenText;
  • WeWork in an $8 billion transaction in which SoftBank provided financing to the company and proposed acquiring a majority of its outstanding shares through a tender offer;
  • Array BioPharma in its $11.4 billion sale to Pfizer;
  • Nightstar Therapeutics plc in its $800 million acquisition by Biogen Inc.;
  • Synergy Pharmaceuticals in its Chapter 11 filing and sale of assets to Bausch Health for $200 million;
  • Select Income REIT in its merger with Government Properties Income Trust to create Office Properties Income Trust;
  • Kelso & Company and affiliates of Blue Wolf Capital Partners in connection with the acquisition of Jordan Health Services from Palladium Equity Partners, and Kelso in connection with the concurrent merger of Jordan Health Services with Great Lakes Caring and National Home Health Care under a combined entity jointly owned with affiliates of Blue Wolf; and
  • Ultragenyx in its successful topping bid for Dimension Therapeutics.



  • J.D., Columbia Law School, 2017
  • B.Phil., University of Pittsburgh, 2014


  • Massachusetts

Sydney S. Gaylin

Associate, Mergers and Acquisitions