The artificial intelligence maker OpenAI may face a costly and inconvenient reckoning with its nonprofit origins even as its valuation recently exploded to $157 billion. Nonprofit tax experts have been closely watching OpenAI, the maker of ChatGPT, since last November when its board ousted and rehired CEO Sam Altman. OpenAI is organized as a nonprofit with a mission to develop artificial intelligence, and it later added subsidiary for-profit entities under the nonprofit’s control. Now, some of these experts believe that OpenAI may have reached or exceeded the limits of how nonprofits and for-profits are allowed to interact.