U.S. District Court Judge Florence Y. Pan announced the decision in a brief statement Monday, adding that much of her ruling remained under seal at the moment because of confidential information and highly confidential information. She asked the two sides to meet with her Friday and suggest redactions.

Penguin Random House quickly condemned the ruling, which it called an unfortunate setback for readers and authors. In its statement Monday, the publisher said it would seek an expedited appeal.

Assistant Attorney General Jonathan Kanter of the Justice Departments Antitrust Division praised the decision, saying in a statement that the decision protects vital competition for books and is a victory for authors, readers, and the free exchange of ideas.

He added: The proposed merger would have reduced competition, decreased author compensation, diminished the breadth, depth, and diversity of our stories and ideas, and ultimately impoverished our democracy.

Pans finding was not surprising through much of the 3-week trial in August she had indicated agreement with the Justice Departments contention that Penguin Random Houses plan to buy Simon & Schuster, for $2.2 billion, might damage a vital cultural industry.

But it was still a dramatic departure from recent history in the book world and beyond. The publishing industry has been consolidating for years with little interference from the government, even when Random House and Penguin merged in 2013 and formed what was then the biggest publishing house in memory. The joining of Penguin Random House and Simon & Schuster would have created a company far exceeding any rival and those opposing the merger included one of Simon & Schusters signature writers, Stephen King, who testified last summer on behalf of the government.

King tweeted Monday that he was delighted by the ruling, adding: The proposed merger was never about readers and writers; it was about preserving (and growing) PRHs market share. In other words: $$$.

The Biden Justice Department has been pushing forward with aggressive enforcement of federal antitrust laws that officials say aim to ensure a fair and competitive market.

Mondays news follows recent losses for the department in two significant antitrust cases in separate federal courts. The DOJ lost its bid to block a major U.S. sugar manufacturer, U.S. sugar, from acquiring its rival Imperial Sugar Co., one of the largest sugar refiners in the nation. The prosecutors signaled that they intended to appeal the decision. They also were stymied in their effort to block the roughly $8 billion acquisition by UnitedHealth Group, which runs the largest U.S. health insurer, of Change Healthcare, a healthcare technology company.

The DOJ also has been battling American Airlines and JetBlue in an antitrust trial in federal court in Boston, challenging their regional partnership in the Northeast, which the government calls a de facto merger.

The Justice Departments case against Penguin Random House did not focus on market share overall or on potential price hikes for customer. The DOJ instead argued that the new company would so dominate the market for commercial books, those with author advances of $250,000 and higher, that the size of advances would go down and the number of releases would decrease.

For Penguin Random House and the New York-based publishing world, the trial in August proved an often uncomfortable airing of business practices, internal disagreements and missed opportunities. Executives on the stand spoke of bestselling works they failed to acquire and acknowledged that most books dont make money. Emails and private text messages revealed tension among top Penguin Random House officials.

I apologize for the passionate language, Penguin Random Houses global, CEO Markus Dohle, testified after some text messages were displayed.

Dohle had promised that imprints of Penguin Random House and Simon & Schuster would still be permitted to bid against each other for books. But he acknowledged under oath during the trial that his guarantee was not legally binding. Pan otherwise persistently challenged Penguin Random Houses assurances that the merger would not reduce competition.

Simon & Schuster will likely end up under new ownership, no matter the outcome of any legal appeals. The publisher had been up for sale well before the Penguin Random House deal was announced late in 2020 and the publishers corporate parent, Paramount Global, has said it did not see Simon & Schuster as part of its future. Under bidders against Penguin Random House included Rupert Murdochs News Corp, which owns HarperCollins Publishers.

Penguin Random House and corporate owner Bertelsmann would have to pay a termination fee of around $200 million to Paramount should the merger fall through, according to the terms of the proposed sale.

Simon & Schuster is one of the countrys oldest and most successful publishers, with authors ranging from King and and former Secretary of State Hillary Clinton to Colleen Hoover and Doris Kearns Goodwin. Authors at Penguin Random House include Clintons husband, former President Bill Clinton, Where the Crawdads Sing novelist Delia Owens and historian Robert A. Caro.

In a company memo Monday shared with The Associated Press, Simon & Schuster CEO Jonathan Karp sought to reassure employees that despite this news, our company continues to thrive. We are more successful and valuable today than we have ever been, thanks to the efforts of all of you on behalf of our many magnificent authors.

Pan, meanwhile, has since been appointed to the U.S. Court of Appeals for the D.C. Circuit, replacing Ketanji Brown Jackson after she was nominated by Biden and approved by the Senate for the Supreme Court.

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The initial strain, reported in January, failed to take flight. Reports of additional Delta-Omicron hybrids, in multiple locations across the globe, later emerged, then fizzled.

But in the waning days of 2022, the Deltacron phenomenon is backif it ever left. This time its in the form of new COVID variants XBC, XAY, and XAW.

In a worst-case scenario, a Delta-Omicron hybrid could be as deadly as the Delta variantwhich killed about 3.4%of those it infected, nearly double that of Omicron, according to a 2022 study published in Nature Reviews Immunology. It could also feature the record-setting transmissibility of Omicron. 

But predicting the severity of such a strain is even more difficult because scientists arent sure exactly why Omicron causes less severe disease in many people, when compared to Delta.

XBCa combination of Delta and stealth Omicron BA.2 circulating in Asian countries like the Philippineshas the greatest potential in the group for transmission, variant tracker Raj Rajnarayanan, assistant dean of research and associate professor at the New York Institute of Technology campus in Jonesboro, Ark., tells Fortune. Its been identified in the U.S., but only in seven cases so far, mainly from California.

Because XBC contains the viral body of Delta and the spike protein of Omicron, its less likely to combine the easy transmissibility of Omicron with the deadly penchant of Delta to hide out in the lungs, experts say.

But they caution that scientists dont fully understand why COVID morphed from a lower respiratory disease in the days of, and prior to, Delta, to a less severe upper respiratory disease for many, as is the case with Omicron. The shift may involve changes outside the spike protein, which the virus uses to attach to and infect human cells. If so, its anyones best guess how future Deltacronseven with Omicron spike proteinswill present in terms of symptoms.

American Pi in the future?

Little is known about XBC, including what its symptoms are. Scientists are aware, however, that the new variant has spawned additional variants, Rajnarayanan points out.

Far less is known about XAY and XAW, first reported in South Africa and Russia, respectively. Other Deltacrons reported earlier this year, including XD in France and XS in the U.S., never took off, perhaps because they were less transmissible than stealth Omicron.

Regardless of how these Deltacrons play out this fall, theres always potential for another. 

While Delta is rarely reported these days, its still being found in some places overseas , like China. And persistent infections in immunocompromised peoplewho may not be aware that theyre immunocompromised or that they have a long-term infectionmay mean Delta will live on, undetected, in patients worldwide.

In animals, Delta variantswith the potential to transmit back to the human populationhave been reported in more than half of U.S. states, usually in deer and mink. While the bulk of Delta infections in animals have been detected in North America, theyve also been reported in Lithuania, Switzerland, Hong Kong, Poland, Latvia, the Netherlands, Canada, South Africa, and more.

A combination of Delta and Omicron is not automatically worse, cautions Ryan Gregory, a professor of evolutionary biology at the University of Guelph in Ontario, Canada.

Deltas ability to dodge the immune systemwhich pales in comparison to that of the latest Omicron strainsin combination with Omicron severity isnt an altogether horrible prospect. Its not nearly as bad as that of a Deltacron with Deltas severity and Omicrons transmissibility and immune-escape capabilities, he said.

Scientists this fall are also keeping an eye on Delta strain AY.103, which picked up some mutations present in some Omicron strains as it evolved in mink and deer. 

Such a varianttransmitted by the animals or immunocompromised patients it developed inhas the potential to be the next big thing in coronavirus evolution, the likes of which havent been seen since Omicron burst onto the scene roughly a year ago.

An American Pi might pop up like this, Rajnarayanan said, referring to the potential of AY.103 or a similar strain of Deltadifferent enough from Omicron to be granted its own Greek letter name by the World Health Organizationto rise to prominence.

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