Twelve states have sued to block Paramount’s takeover of Warner Bros. Discovery, kicking off a high-stakes antitrust battle that could impede the media mega-merger.

The union representing Hollywood screenwriters on Tuesday sued to block Paramount’s PSKY -3.72% $81 billion acquisition of Warner Bros. Discovery WBD 1.41%, a day after a coalition of 12 Democratic st...

"The unlawful merger of these two entertainment behemoths would lead to higher prices, lower quality, and less content for film and television, harming movie theaters, basic cable distributors, and ul...