Paramount, Viacom and CBS are separate companies, all of which use to be part of the same company, but split in 1994. They are controlled by Sumner Redstone, and there has been a pitched battle over control of the companies, as his competence has been challenged by his daughter Sherry Redstone, who also owns positions in the company and stands to inherit his controlling stake once he passes. The boards have been talking about a combination (or re=merging), but recently decided not to merge (or talk about it any further) until next year.
It appears to me, all this fighting over control is putting these combined assets at risk and behind Disney and Comcast, as it has a bunch of assets already, but is not pursuing the talent or creating the IP / Content that Disney and Netflix are producing.
Not sure either what Starz gets or how it would be viewed as strategic, when they need to put their humpty dumpty self (Paramont, Viacom and CBS) back together again.
I agree we should watch Sony as a company to make a move here soon! Sony announced a big stock buy back this week, trying to support its stock price, because it is struggling with its bread and butter video game business, and electronics. Columbia pictures is an attractive asset but (my opinion) has never been core to Sony. I would like to see them sell the Spiderverse rights back to Marvel, but think it is a long shot as there wouldn't be much left to Columbia if they did....