It was a performance art piece that became famous: A woman who felt that Columbia University had mishandled her charge of rape against a fellow student turned that anger into her senior arts thesis, a yearlong project in which she carried a 50-pound mattress whenever she was on the Morningside Heights campus.

The woman, Emma Sulkowicz, won national acclaim and was largely embraced by her fellow students, who often helped her carry her burden, which she even brought to a graduation ceremony in May 2015.

The accused man, Paul Nungesser, who was cleared of responsibility in the case by a university disciplinary panel, found himself alternately hounded and ostracized, and condemned at a campus rally and on fliers posted around campus. A month before he and Ms. Sulkowicz received their degrees, he sued Columbia, accusing it of supporting what he called an “outrageous display of harassment and defamation” by giving Ms. Sulkowicz academic credit for her project.

Columbia said late this week that it had reached a settlement with Mr. Nungesser, the terms of which it did not disclose. But the university said in a statement: “Columbia recognizes that after the conclusion of the investigation, Paul’s remaining time at Columbia became very difficult for him and not what Columbia would want any of its students to experience. Columbia will continue to review and update its policies toward ensuring that every student — accuser and accused, including those like Paul who are found not responsible — is treated respectfully and as a full member of the Columbia community.”