Sullivan & Cromwell Global Head of M&A Melissa Sawyer tells Bloomberg that deal volume will be the key signal that M&A are truly coming back. She says renewed activity in the IPO market is an early indicator that private equity sponsors may soon feel confident enough to exit portfolio companies and recycle capital into new deals. Sawyer adds that a shift in tone from Washington has helped restore confidence among companies considering transactions. She joined the conversation on "Bloomberg Deals" with Dani Burger. (Source: Bloomberg)