NEW YORK — Two top editors at Penguin Random House are leaving as the country’s leading trading publisher continues to transform during a period of uncertain revenues and generational change.

The Knopf Doubleday Publishing Group, a Penguin Random House division, announced Monday the dismissals of Alfred A. Knopf publisher Reagan Arthur and Pantheon/Schocken publisher Lisa Lucas. A publishing official who was not authorized to comment publicly and spoke on condition of anonymity, said that the restructuring was for financial reasons. Knopf and Pantheon/Schocken are two of the industry’s most established literary publishers and Arthur and Lucas two of the most widely liked editors. Their departures were met with surprise and dismay around the industry; author Sara Schaff wrote on X that the news was “demoralizing and short sighted.”

The book market has softened since early in the pandemic, when sales surged amid shutdowns in the entertainment industry and beyond. In a year-end company letter sent in December 2023, Penguin Random House CEO Nihar Malaviya referred to “very difficult and challenging” changes facing the company. On Monday, Knopf Doubleday publisher Maya Mavjee said the latest “realignment” was “necessary for our future growth.”

“Our new structure –- consisting of a nimble, concentrated leadership team –- will enable us to meet the trials of an ever-shifting marketplace, hone the shape and focus of our imprints, and continue to allow us to do what we do best: publish great books,” Mavjee said.

Jordan Pavlin, currently Knopf’s editor in chief, will now also serve as publisher. At Pantheon, vice president-editorial director Denise Oswald will report to the publisher of Doubleday, Bill Thomas.

Over the past few years, much of Penguin Random House’s leadership team has retired, died or otherwise departed. CEO Markus Dohle left after the publisher’s purchase of rival Simon & Schuster was blocked in 2022 by a federal judge, and numerous longtime officials accepted buyouts. Arthur’s immediate predecessor at Knopf, Sonny Mehta, died in 2019. One of Knopf’s most celebrated editors, Robert Gottlieb, died last year.

Arthur, who joined Knopf in 2020 after heading Little, Brown and Company, had worked with Ian McEwan and Nathan Hill among others. A Knopf novel, Jayne Anne Phillips’ “Night Watch,” is this year’s winner of the Pulitzer Prize for fiction. Lucas was also hired in 2020, after serving four years as executive director of the National Book Foundation, where she had been the first Black person and first woman to head the non-profit organization. Her books at Pantheon included Nana Kwame Adjei-Brenyah’s novel “Chain-Gang All-Stars,” a National Book Award finalist, and Laura Warrell’s novel “Sweet, Soft, Plenty Rhythm, a finalist for the PEN/Faulkner prize.

Lucas wrote on X that she learned of her dismissal a few days after being honored by her alma mater, the University of Chicago, for professional achievement. The news also came almost exactly six years since the death of her father, musician Reggie Lucas.

“WILD RIDE FOR ONLY FOUR DAYS,” she wrote.

Adjei-Brenyah tweeted that Lucas had made Pantheon one of the industry’s most diverse imprints and that “to not even allow” her five years on the job was “pretty shameful.” Pantheon author Nina McConigley wrote on X: “As an author who signed with @PantheonBooks — @likaluca was one of the reasons I was so excited. She is a role model in so many senses of the word. So so brokenhearted.”