His brother, David T. Leighton, is a professor at the University of Notre Dame specializing in transport phenomena.

[4] Leighton discovered a solution to free up web congestion using applied mathematics and distributed computing.

He also holds patents involving content delivery, Internet protocols, algorithms for networks, cryptography, and digital rights management.

Leighton has the Presidential Informational Technology Advisory Committee (PITAC) and chaired its subcommittee on cybersecurity.

[6] He is on the board of trustees of the Society for Science & the Public (SSP) and of the Center for Excellence in Education (CEE), and he has participated in the Distinguished Lecture Series at CEE's flagship program for high school students, the Research Science Institute (RSI).