[2] Diller began his career through a family connection[4] in the mailroom of the William Morris Agency after dropping out of UCLA after three weeks.

His proximity to the company's file room meant that he could spend free time reading through the archives and learning the entire history of the entertainment industry.

[5] He was hired as an assistant by Elton Rule, then West Coast head of ABC,[1] who was promoted to network President at the same time Diller went to work for him in 1964, taking him on to New York City.

With Diller at the helm, the studio produced hit television programs such as Laverne & Shirley (1976), Taxi (1978), and Cheers (1982) and films that include Saturday Night Fever (1977), Grease (1978), Raiders of the Lost Ark (1981) and sequel Indiana Jones and the Temple of Doom (1984), Terms of Endearment (1983), and Beverly Hills Cop (1984).

[12] New York Times journalist Calvin Sims noted on December 11, 1992, that Diller sought "to turn the shopping channel into an on-line entertainment and merchandising service in which the subscriber and the cable company can freely interact".

[22] Paramount parent company Gulf + Western also owned the Madison Square Garden Sports Corp., which helped create the USA Network with Koplovitz.

[25] Under Diller's leadership, the USA Network also showed tolerance to the growing WWF angles which were breaking with traditional censorship and were considered controversial, with even his USA Network spokesman David Schwartz describing an incident where the wrestler Jacqueline exposed one of her breasts as "not worse than anything you see on broadcast television at that time of night, such as NYPD Blue".

[32] The new headquarters for the IAC/InterActiveCorp, the IAC Building was designed by Frank Gehry and opened in 2007 at 18th Street and the West Side Highway in Manhattan's Chelsea neighborhood.

The western half of the block is dedicated to the building, which stands several stories taller than the massive Chelsea Piers sporting complex just across the West Side Highway.

[33] Diller was "the highest-paid executive [of fiscal year 2005]", according to a report by The New York Times on October 26, 2006, with total compensation in excess of $295 million (mostly from stock).

[36] Aereo went out of business in June 2014 after the United States Supreme Court ruled that its method of streaming media content violated copyright laws.

[36] Since 2013, Diller has co-produced more than ten Broadway shows in partnership with Scott Rudin, including To Kill A Mockingbird, West Side Story, Carousel, The Humans, Three Tall Women, Gary: A Sequel to Titus Andronicus, and A Doll's House, Part 2.

[38] In early 2020, Diller took over Expedia's day-to-day operations alongside the vice chairman Peter Kern, after the company's CFO stepped down in December 2019.

[citation needed] On March 9, 2022, The Wall Street Journal reported that Diller, David Geffen and his stepson, Alex Von Furstenberg were being investigated by the Securities and Exchange Commission and the United States Department of Justice for insider trading of options on Activision Blizzard just three days before Microsoft's announced acquisition.

[51] In 2015, Diller criticized Republican candidate Donald Trump's impact on political discourse and said he would leave the country if he was elected.

[53] In 2024, Diller was among those who called for U.S. President Joe Biden to end his bid for re-election after his poor debate performance and other disconcerting signs on the campaign trail.

[54] In 2011, the Diller-von Fürstenberg Family Foundation announced a donation of $20 million to support the completion of the High Line park in Manhattan.

[56] In 2015, Diller and his wife committed to donate $260 million toward Little Island, a public park and performance space on a reconstructed pier 55 in the Hudson River in New York City.