Seung-yoon Lee's venture Poseidon has formed a partnership with Toss on a user-participation AI training data business, launching an experiment in a participatory data economy. Poseidon has built a structure to collect first-person behavioral data essential for physical AI through the DATA network, the Numo mini app and a Task-to-Earn model, while providing transparent compensation. Poseidon aims to secure leadership in the physical AI era by supplying datasets to global frontier AI research labs, backed by a $15 million seed investment from a16z and partnerships including Oto on Hugging Face and Miso, a robotics data partner. Seung-yoon Lee previously sold web novel platform Radish to Kakao for about $360 million and later built blockchain project DATA.