Wednesday was a day of musical chairs for the New York securities bar. One top securities litigator and government enforcer opted to return to his longtime law firm, while another prominent practitioner landed at his fourth firm in eight years.

George Canellos, who announced his resignation as codirector of enforcement at the Securities and Exchange Commission in early January, is rejoining his old firm, Milbank, Tweed, Hadley & McCloy, as head of global litigation. Canellos’ return to Milbank, which ends a monthlong guessing game about his destination, becomes official in mid-March, according to the firm.