Tsutomu Shimomura

Early Life and Education

Tsutomu Shimomura was born on October 23, 1964, in Japan. He is the son of Osamu Shimomura, who was awarded the Nobel Prize in Chemistry in 2008. He grew up in Princeton, New Jersey, where he attended Princeton High School. At the California Institute of Technology (Caltech), he studied under Nobel laureate Richard Feynman.

Early Career

Following his time at Caltech, Shimomura joined Los Alamos National Laboratory, where he worked as a staff physicist alongside Brosl Hasslacher and others on topics including lattice gas automata. In 1989, he became a research scientist in computational physics at the University of California, San Diego, and also served as a senior fellow at the San Diego Supercomputer Center. During this period he developed expertise in computer security and undertook work for the National Security Agency.

In 1992, Shimomura testified before Congress on issues related to the privacy and security vulnerabilities of cellular telephones. Author Bruce Sterling, who was present at the same hearing, later recalled Shimomura's notably casual appearance — sandals and cutoff shorts — in contrast to the formal attire of other witnesses.

The Kevin Mitnick Case

Shimomura is best known for his involvement in the 1995 pursuit of computer hacker Kevin Mitnick. He assisted the FBI in tracking and ultimately locating Mitnick, leading to Mitnick's arrest. During the same year, Shimomura also received prank calls that helped popularize the phrase "My kung fu is stronger than yours" as a cultural reference to hacking.

Shimomura and journalist John Markoff co-authored Takedown: The Pursuit and Capture of Kevin Mitnick, America's Most Wanted Computer Outlaw (Hyperion Books, 1996), a first-hand account of the pursuit. The book was subsequently adapted into the film Track Down (2000), in which Shimomura made a brief cameo appearance.

Later in the 1990s, Shimomura worked for Sun Microsystems.

Notable Work

In January 1996, Shimomura was a co-author on the paper "Minimal Key Lengths for Symmetric Ciphers to Provide Adequate Commercial Security," alongside prominent cryptographers including Bruce Schneier, Ronald L. Rivest, Matt Blaze, and Whitfield Diffie, among others.

Neofocal Systems

Shimomura was a founder of Neofocal Systems, a privately held fabless semiconductor company. He served as both CEO and CTO of the company until 2016.

Criticism

The account of events presented in Takedown has been disputed by Kevin Mitnick and others. California author Jonathan Littman published a 1996 book, The Fugitive Game: Online with Kevin Mitnick, which presented Mitnick's version of events and raised allegations of journalistic impropriety against Markoff, questioned the legality of Shimomura's involvement in the case, and suggested that portions of Takedown were fabricated for self-serving purposes. Mitnick's autobiography, Ghost in the Wires, further elaborated on concerns that Shimomura's conduct during the case was both unethical and illegal.