Simpson, Thacher & Bartlett has gone back to Paul Weiss Rifkind, Wharton & Garrison to recruit its second partner from the firm in a week, with M&A lawyer Justin Rosenberg joining Simpson in New York, the firm announced Monday.

Both Paul Weiss and Simpson Thacher have made impactful additions in the last week. Simpson Thacher added Tracey Zaccone from Paul Weiss and David Teh from Latham & Watkins last week to lead its private credit practice, while Paul Weiss lured former Cravath, Swaine & Moore heavy-hitter (and longtime Morgan Stanley global M&A chair) Rob Kindler to the firm on June 6th.