A mergers and acquisitions associate at Sullivan & Cromwell has sued the firm alleging a pattern of discrimination against him on the basis of sexual orientation.

In a pro se complaint filed Tuesday in Manhattan Supreme Court, Aaron B. Charney accuses several of the firm’s top partners of discriminating against him because he is gay. He also claims the firm initiated a retaliatory campaign after he filed an internal complaint, culminating in the issuance of a fabricated performance review.