Hamachi is a Japanese investment company that was one of InGen‘s principal investors. As a principal investor, it can be assumed that they owned a large enough stock in the company to either be on the Board or in an advisory position. Hamachi was in contact with Cowan, Swain and Ross, who were the legal offices that represented InGen. Hamachi had a representative in San Jose which informed the offices of the mysterious biting incidents by strange lizards along the coast, which was one of the factors that made Daniel Ross send Donald Gennaro to investigate the island.
Jurassic Park by Michael Crichton page 49 (First Edition, Thirty Fourth printing)