OpenAI said on Tuesday it had converted its main business into a for profit corporation, the conclusion of a lengthy and fraught legal saga. A crucial regulator, Kathy Jennings, the Delaware attorney general, said she approved the plan for the startup, which began as a non profit in 2015, to change to a public benefit corporation, a type of for profit entity that expresses commitment to bettering society. The company also said it had reorganized its ownership structure and signed a new...