Howard Stern would have plenty of options, including Netflix or Apple Music, if he were to leave Sirius XM when his contract expires next month, said Mel Karmazin, former CEO of the satellite radio service.



"I really have no idea as to what he's going to do," Karmazin, a longtime supporter of Stern, told CNBC's "Squawk Box" on Wednesday. "He's an extraordinary performer. I think that he would have a tremendous amount of alternatives."

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One of Stern's options, according to Karmazin, could involve Stern's 30-year library of radio shows and other material.

"He owns it all. He could syndicate it. He doesn't have to work anymore. He could either sell his company or he could do a 'Law and Order,' a 'Friends,' a 'Seinfeld' and make a whole bunch of money because everyone is in need of content," said Karmazin.

"Howard could also do something, arguably a la Netflix-type," Karmazin speculated. "It's original content. He does the video ... [and] it could be a TV show that could be available worldwide."

Karmazin also said he thinks Apple, which just started its own music streaming service, would be a good fit for Stern. In fact, he said he didn't see any reason why Apple wouldn't want to just buy Sirius.

But as a paying subscriber to Sirius, Karmazin said he hopes "The Howard Stern Show" doesn't go anywhere.

"I think Sirius would be in a position of paying him whatever it takes to keep him," he continued. "My bet would be he would stay, but I have really don't have an idea."

Stern decided earlier this year to leave his lucrative side job on primetime television as a judge on NBC's "America's Got Talent." (Simon Cowell, formerly of "American Idol" and "The X Factor," is taking Stern's place, and plans to continue as executive producer of "AGT.")



Analysts estimate that Stern's current Sirius XM contract is worth $80 million a year.

"I think Howard loves money. I don't say that in any pejorative way," Karmazin said. "He's working. He knows how much money other people are making off of that [radio] show. And I think he wants his fair share or unfair share."

Stern and Karmazin go way back.

In 1985, when Karmazin ran Infinity Broadcasting, he hired Stern after the shock jock was fired from WNBC radio. Their fortunes rose together as Infinity was purchased by CBS parent Westinghouse in 1996. Viacom then bought CBS in 2001. (Viacom and CBS in 2005 split into two companies). Along the way, Karmazin, who served as CEO of CBS and then president of Viacom, stuck with Stern despite steep government indecency fines.

Shortly after Stern took his terrestrial radio show in 2004 from Viacom to then-Sirius Radio, Karmazin followed to lead the fledgling satellite radio company. Karmazin, with Stern in his stable, oversaw the merger of Sirius and its larger rival XM, which took 17 months to get government approval.

In 2013, John Malone's Liberty Media took a majority ownership of Sirius XM. In anticipation of that move, Karmazin resigned as Sirius CEO.