When Mike (Patrick J. Adams) connives his way into the Harvard tour, he tells a prospect Dean Wormer wants to see the top prospects in his office. Dean Wormer was the dean of Faber College in the movie National Lampoon's Animal House (1978).
Although set in in Manhattan, the series is filmed in Toronto. In many episodes you see two or three yellow cabs parked outside the firm's office but you never see any yellow cabs moving on the street. And, just occasionally, you see a shop name, clearly in Toronto.
The man who had sexually harassed a former employee was president of a company named Devlin McGregor. Devlin McGregor was also the name of the "bad-guy" company in the movie "The Fugitive (1993)", plus an episode of Boston Legal (2004) (The Cancer Man Can) and an episode of Leverage (2008) (The Double-Blind Job).
At 00:46:51 Mike (Patrick J. Adams) is referencing the movie, The Godfather (1972), when he says: "I feel like Michael Corleone in that scene where that fat guy teaches him how to shoot that gun." And as Harvey (Gabriel Macht) confirmed, "that fat guy" is none other than Clemenza.