Musannaf Ibn Abi Shayba 13:3246

Abu Bakr narrated to us, he said: Abu Usama narrated to us, from Uthman ibn Ghiyath, he said: Al-Hasan was asked about a ship that sinks in the sea, in which is the property of various people. He said: Whatever the sea casts upon its shore, it belongs to its owner. And whoever dives for something and extracts it, it belongs to him.