Donna Speciale, WarnerMedia

The ad sales chief left the company in July, just a week after wrapping this year’s upfront negotiations. (Also departing: Dan Riess, evp of Ignite, and Frank Sgrizzi, evp of portfolio sales and client partnerships.) She had been with the company since 2012. Her position still hasn’t been filed five months later; for now, WarnerMedia chief revenue officer Gerhard Zeiler, named in March to oversee Speciale and her team as part of the WarnerMedia affiliates and advertising sales group, is leading ad sales as interim president.

Richard Plepler, HBO

He started at HBO in 1992 and helped build the network into a premium-content powerhouse, becoming CEO in 2013. But Plepler left the network in February ahead of a major consolidation of WarnerMedia under parent company AT&T. A week later, Robert Greenblatt was named chairman, WarnerMedia Entertainment and Direct-to-Consumer, overseeing HBO as well as TNT, TBS, truTV and the direct-to-consumer business.

David Levy, Turner

Plepler wasn’t the only longtime WarnerMedia exec who departed as new owner AT&T overhauled the company. Turner president Levy, who joined the company in 1986, also exited in February. He transitioned to the NBA, signing on as CEO of the Brooklyn Nets in September. But Levy left the post less than two months later.

Sean Moran, Viacom

He took over as Viacom ad sales chief in 2016, and this fall returned the company’s domestic advertising to full-year growth for the first time in six years. However, he was a casualty of this month’s CBS-Viacom merger—losing out on the top ad sales job, which went to CBS’ Jo Ann Ross—and exited the company following the deal’s close.

Kevin Tsujihara, Warner Bros.

The chairman and CEO stepped down in March, following a report that he had pushed for auditions for an actress after the two had an apparent sexual relationship. In June, WarnerMedia hired Ann Sarnoff as the company’s new chairwoman and CEO.

Scott Collins, AMC Networks

Collins, named AMC Networks in 2008, stepped down as ad sales chief in August after being named to the position in 2017. Kim Kelleher was hired to replace him a month later.

Kent Alterman, Comedy Central, Paramount Network and TV Land

Alterman spent two decades at Viacom, and ran Comedy Central since 2016 before the TV Land and Paramount Network oversight last year. But he departed in November as a result of a pre-merger shakeup before CBS and Viacom reunited in December. The three networks are now overseen by Chris McCarthy, who also runs MTV, VH1, CMT, Logo and Smithsonian Channel.

Sarah Levy, Viacom Media Networks

The COO, also a two-decade Viacom vet, left in November as part of that same restructuring ahead of the merger.

Wade Davis, Viacom

Viacom’s CFO exited the company following the CBS-Viacom merger, as CBS’ CFO Christina Spade was tapped to continue her role for the new company.

Christina Miller, Adult Swim, Cartoon Network, Boomerang, TCM

Last month, the network president said she would be leaving WarnerMedia at year’s end, following a 15-year run at the company. Michael Ouweleen, evp and CMO for Cartoon Network, Adult Swim and Boomerang, is serving as the interim president.

Jim Lanzone, CBS Interactive

The CEO, who led CBS Interactive since 2011, departed at year’s end to become executive-in-residence at Benchmark Capital. President and COO Marc DeBevoise was promoted to CEO as his replacement.

Bryan Wiener, Comscore

The measurement company CEO abruptly resigned in March over what he called “irreconcilable differences,” after just 10 months at the company. President Sarah Hofstetter exited at the same time. The company found his replacement in November, tapping former Rentrak CEO Bill Livek as its new CEO and executive vice chairman.

Adam Stotsky, E!

The E! Entertainment president, an 18-year NBCUniversal veteran, stepped down in September with Frances Berwick, president of NBCUniversal Cable Entertainment’s lifestyle networks, assuming his duties.

Chris Linn, truTV

Linn left the president position of WarnerMedia in May after the company expanded chief content officer Kevin Reilly’s purview to include truTV as well.

George Cheeks, NBC

After a year working alongside Paul Telegdy as co-chairman of NBC Entertainment, Cheeks exited the network in October—but remained with the company—as part of a broader NBCUniversal leadership shuffle. He shifted to a new role as vice chairman of NBCUniversal Content Studios, reporting to Bonnie Hammer, who was simultaneously named chairwoman of NBCUniversal Content Studios.