US author Stephen King has given evidence against his own publisher at a competition trial over the proposed merger of two book giants.

The 74-year-old appeared as a government witness in the federal anti-trust lawsuit against the merger of Penguin Random House and Simon & Schuster, King’s long-time publisher.

“My name is Stephen King. I’m a freelance writer,” King said upon being asked to identify himself.

The Justice Department is bidding to convince District Judge Florence Pan that the proposed combination of Penguin Random House and Simon & Schuster would thwart competition and damage the careers of some of the most popular authors.

Book Publishers Antitrust Stephen King
Author Stephen King autographs a book as he leaves the court (Patrick Semansky/AP)

King’s career, with so many bestsellers he could only offer an estimate, has come amid waves of consolidation in the industry.

As he noted in his remarks in the Washington DC court, there were dozens of publishers in New York when his breakthrough novel, Carrie, came out in 1974 and he has seen many of them either acquired by larger companies or forced out of business.

Now, New York publishing is often a story of the so-called Big Five – Penguin Random House, Simon & Schuster, HarperCollins Publishing, Hachette Book Group and Macmillan.

The publisher of Carrie, Doubleday, is now part of Penguin Random House. So is another former King publisher, Viking Press.

Over the first two days, lawyers for the two sides have presented contrasting views of the book industry.

The Justice Department sees an increasingly limited market for bestsellers, with the Big Five well in command. Penguin Random House’s side sees book publishing as dynamic and open to many, with the proposed merger having limited impact.

Book Publishers Antitrust Stephen King
Author Stephen King opposes the merger of two publishers (Patrick Semansky/AP)

King’s appearance in US District Court in Washington brought a narrative of the evolution of book publishing toward the dominance of the Big Five companies.

As government lawyer Mel Schwarz walked King through his history starting as a new author in the 1970s and his relationships with agents and publishers, King homed in on a critique of the industry as it is now.

“The Big Five are pretty entrenched,” he said.

Under questioning later in the day, Simon & Schuster CEO Jonathan Karp detailed a world of fiercely competitive bidding among publishers — including between his firm and Penguin Random House — for authors’ works, sometimes offering millions of dollars for high-profile writers.

With his possible future boss, Penguin Random House Markus Dohle, among those looking on in the courtroom, Karp rejected the Big Five moniker, calling it “parochial and ethnocentric”.

“I think there are a lot of good publishers all over the country. It’s not all about us,” Karp said.

As an example, he said the nearly 100-year-old Simon & Schuster has endured more aggressive competition recently from Amazon’s book publishing business.

But Justice Department lawyer Jeff Vernon brought forward a message Karp had sent to John Irving, his favourite author, saying he did not think the government would allow Simon & Schuster and Penguin Random House to merge. “That’s assuming we still have a Department of Justice,” Karp wrote in the message.

King’s displeasure about the proposed merger led him to voluntarily testify for the government.

“I came because I think that consolidation is bad for competition,” King said. The way the industry has evolved, he said, “it becomes tougher and tougher for writers to find money to live on”.

King expressed scepticism toward the two publishers’ commitment to continue to bid for books separately and competitively after a merger.

“You might as well say you’re going to have a husband and wife bidding against each other for the same house,” he quipped. “It would be sort of very gentlemanly and sort of, ‘After you’ and ‘After you’,” he said, gesturing with a polite sweep of the arm.