Alison S. Ressler

Ressler is the first female and first non-New York partner to join Sullivan & Cromwell's senior management committee. She heads the firm's California practice, where she is a leading authority on mergers and acquisitions, corporate governance and capital markets. She specializes in blockbuster deals including client Valeant Pharmaceuticals International Inc.'s $55 billion unsolicited offer to acquire Botox maker Allergan Inc., one of the healthcare sector's most complex takeover efforts.

The hostile attempt failed. But it was regarded as a significant innovation because, she said, a "strategic" like Valeant had never before teamed up with a hedge fund, in this case activist investor William A. Ackman's Pershing Square Capital Management LP, to pursue an acquisition target.

"When you have complex transactions involving multiple partners you have to be creative," Ressler said. Even though the try fell through, the Valeant-Pershing Square partners acquired a 9.9 percent stake in Allergan. Its subsequent sale to Actavis PLC earned the partners a reported $2.3 billion. "Our shareholders made a tremendous amount," Ressler said. "Allergan sold itself at a high premium that would never have been accomplished if it were not triggered by our having taken a stake in it. Structuring that transaction was truly innovative."

Ressler did complete Valeant's $15.8 billion acquisition of Salix Pharmaceuticals Inc. in 2015.

"That was a busy year," she said of 2015. It included advice to ATL Invesco, which bought the National Basketball Association's Atlanta Hawks for a reported $850 million, a deal that fit well with Ressler's love of pro basketball. "I've been a Lakers fan for years," she said, "but I'm a Stephen Curry fan too -- how can you not be?" she said of the Golden State Warriors' superstar.

The Hawks sale expanded her allegiances following back-to-back victories in March at Staples Center. "They were just in town to play the Lakers and the Clippers and won both games," she said. "I'm a fan of the Hawks, now that I did that deal."

John Roemer