With deal volume up during the first quarter, O'Melveny & Myers, Shearman & Sterling and Covington & Burling made notable additions Monday to bolster their M&A ranks in New York.

O'Melveny, whose leadership last month vowed to ramp up its transactional offering following a disappointing financial year in 2014, announced Monday its hire of a new co-head of U.S. private equity and M&A in Tobias “Toby” Knapp, who previously served as a member of the firm-wide management committee at Jenner & Block.

Knapp is a former Davis Polk & Wardwell associate who joined Jenner a dozen years ago. He served as co-chair of the private equity and investment funds practice and chair of the New York corporate practice at Jenner, which saw profits per partner leap more than 30 percent last year to $1.6 million, slightly more than O'Melveny's average PPP in 2014.