As streaming continues to grow, media giants Fox and NBCUniversal are reportedly interested in buying some of the earlier over-the-top services.

Fox has expressed interest in ad-supported streaming service Tubi, according to a report in the Wall Street Journal.

NBCUniversal is in advanced talks to acquire Vudu from Walmart, the WSJ said. Walmart bought Vudu for $100 million. Last year Vudu started streaming original programming, in addition to acquired movies and TV shows.

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The paper previously reported that NBCU’s parent company Comcast was in exclusive negotiations to acquire Xumo, another ad supported streaming service.

Pluto TV, one of the largest ad-supported streaming services, was acquired last year by Viacom for $340 million and is now one of the fastest-growing parts of what is now ViacomCBS.

With Netflix, Hulu and Amazon Prime siphoning off viewers, major TV companies have been jumping into streaming. Last year the Walt Disney Co. launched Disney+ and later this year AT&T will launch HBO Max and NBCU will launch Peacock. ViacomCBS is looking to beef up its streaming service CBS All Access.

Acquiring Tubi would cost Fox more than $500 million, according to the paper.