After five years under investigation for insider trading, Steven Cohen is considering proposing a deal to prosecutors that would shut his $15 billion hedge-fund firm to outside investors, according to a person familiar with his thinking. Cohen has discussed an agreement under which his SAC Capital Advisors LP would admit wrongdoing but wouldn’t be prosecuted unless it broke the law again, said the person, who asked not to be named because the talks are private. As part of the deal, known as a deferred prosecution agreement, Cohen would close the Stamford, Connecticut-based firm to outside investors and make it a family office that manages his personal fortune. SAC Capital probably would also pay fine. [Bloomberg]