John Parker Hammond was born on March 14, 1928. In 1979, with Norman Atherton, he founded International Genetic Technologies, also known as InGen. With this company, he created a dinosaur preserve, Jurassic Park. However, due to an incident in 1989 during a safety inspection, Hammond was forced to file for Chapter 11. After another incident in 1997 involving a failed expedition to Isla Sorna and the subsequent incident involving a Tyrannosaurus rex accidentally set loose in San Diego, California, he published a memoir called Jurassic Time.
The John Hammond in Trespasser canon is very similar to that which appeared in the films and even share the same actor (Richard Attenborough). John Hammond never personally appears in the game, but is constantly heard in different parts of the levels remarking on certain buildings and dinosaurs in the form of his memoirs. Also, in the town level, it is possible to listen to his computer audio diaries.