[3][4] Cogent was founded in 1999 at the peak of the industry's growth and was funded by angel investors including members of Keiretsu Forum.

[6] In September, 2022, it was announced that Cogent was buying the Sprint Corporation wireline business from T-Mobile for $1.00, assuming some liabilities.

[16] Cogent has been controversial in the ISP market for low bandwidth pricing and its public disputes over peering with AOL (2003),[17] Level 3 Communications (2005),[18] France Telecom (2006),[19] Limelight Networks (2007),[20] Telia Carrier (March 2008),[21] and Sprint Nextel (October 2008).

[30] This is rumored to be closely tied to Cogent leveraging Google's IPv4 traffic via a paid customer or to maintain settlement-free interconnect with another network.[31][speculation?]

In May 2024, Cogent withdrew peering with Tata Communications completely,[37] due to this networks that are single homed behind AS6453 (in APAC) or AS174 will not be able to reach each other.