American horror novelist Stephen King is taking on a new monster: corporate consolidation.

The author was the star witness in an anti-trust trial to block the two biggest US publishers’ $2.2bn merger.

The US Department of Justice called on King to testify about how the proposed tie-up of Penguin Random House and Simon & Schuster could affect authors.

King, 75, told the court in Washington DC that he felt “the move would be bad for competition in the industry”.

Both publishing houses have argued the merger would not hinder competition because the companies would continue to bid against each other for the rights to publish novels, even after the transaction is finalized.

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