The Pacific sleeper shark, Somniosus pacificus, is a sleeper shark of the family Dalatiidae, found circumglobally on continental shelves and slopes in temperate waters between latitudes 70° N and 47° S, from the surface to 2,000 m. Its length is up to 4.4 m (14 ft), although FishBase accepts that it could possibly reach 7 m. In 1990, an enormous Pacific sleeper shark was attracted to a bait in deep water outside Tokyo Bay, Japan and filmed. The shark was estimated by Eugenie Clark to be about 7 m (23 ft) long (some tabloid newspapers, particularly The Sun, made outrageous claims that it was a "Megalodon").
The Pacific sleeper shark feeds on bottom animals including certain types of fish, octopus, squid, crab, tritons, Harbor Seals, as well as carrion. The flesh contains high amounts of urea, so that, if it is eaten raw or fresh, symptoms similar to drunkenness develop. It is one of two creatures (along with the Sperm Whale) that feed on giant squid and colossal squid, as research on the stomach contents of this shark has shown. Since the 7 m (23 ft) shark might have problems catching and devouring a 12 to 14 m (39 to 46 ft) squid, it is believed that the shark may feed on squid carcasses rather than live squid.