Showtime’s Over the Top endgame: CEO

Showtime Networks is eyeing an untapped market for its latest over-the-top video streaming service, Chairman and CEO Matthew Blank said Thursday.

"There are 10-to-12 million broadband subscribers that don't take video services, and they should be a terrific target for us, especially starting out," Blank said on CNBC's "Squawk Box."

Blank made his remarks a day after the company said it will launch its standalone streaming service on Apple devices next month. The service will cost users $10.99 a month, $4 lower than Time Warner's HBO Now.

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The launch of standalone streaming services—those not requiring a cable contract—follows years of falling TV viewership as people switch to services provided by companies such as Netflix and Amazon.com.

Showtime is offering a 30-day free trial for its standalone service for those signing up through Apple in July. It said other platforms and providers will be announced later.

—Reuters contributed to this report.