LOS ANGELES » Sony Pictures Entertainment warned media outlets on Sunday against using the mountains of corporate data revealed by hackers who raided the studio’s computer systems in an attack that became public last month.

In a sharply worded letter sent to news organizations, including The New York Times, David Boies, a prominent lawyer hired by Sony, characterized the documents as "stolen information" and demanded that they be avoided, and destroyed if they had already been downloaded or otherwise acquired.

The studio "does not consent to your possession, review, copying, dissemination, publication, uploading, downloading or making any use" of the information, Boies wrote in the 3-page letter, which was distributed Sunday.

Sony’s action comes 20 days after hackers first infiltrated its computer systems and amid silence on the crisis from peer studios that Sony had hoped would publicly voice support. It comes after a flood of damaging media reports based on the hacked documents, which included information on Sony’s salaries, business negotiations, employee health records, and private email conversations. One of the most volatile email exchanges, which included racially insensitive banter about President Barack Obama’s imagined preference for black-themed movies, prompted public apologies by Amy Pascal, co-chairwoman of Sony Pictures, and by a prominent producer, Scott Rudin.

Over the weekend, the hackers, who have pressed Sony to withdraw its upcoming comedy "The Interview," promised further data dumps by Christmas, when the film is scheduled to be released. The plot involves an attempt to assassinate the North Korean leader Kim Jong Un.

Until now, the data has provided a feast for traffic-hungry websites like Fusion and those owned by Gawker Media, along with some mainstream news organizations like Bloomberg, which last week posted an article – without citing names – revealing details of employee medical records that were made public by the hackers.

The New York Times has reported on some Sony emails and company-related data based on the accounts of other news organizations and on statements from Sony executives. Sony representatives have acknowledged the authenticity of the emails and data.

Heather L. Dietrick, general counsel for Gawker Media, said the organization was not yet aware of Boies’ letter. She said Gawker reports had been confined to "very newsworthy" and "revelatory" documents. A Bloomberg spokesman declined to comment.

As Sony has been battered, other major studios and the Motion Picture Association of America until now have offered virtually no public backing. Asked about the stance of Christopher Dodd, the association’s chief executive, a spokeswoman said he was not immediately available.

But the association issued a statement that read in part: "From the highest levels of our organization working with the highest levels of theirs, we are doing anything and everything that Sony believes could be helpful and will continue to do so."

According to several people who were briefed on the matter, and who spoke on condition of anonymity because they were not authorized to comment, Dodd and Sony’s chairman, Michael Lynton, have sought, without success, to organize a letter of support from fellow studio chiefs. The letter did not materialize, according to one of those people, in part because rival studio chiefs felt it would be ineffective and might look like "a publicity stunt."

Another person briefed on the discussions said Sony’s search for assistance was complicated by the studio’s Japanese ownership and a cultural reluctance by those in Japan to risk fanning the flames with public action. Some of Sony’s counterparts have also been reluctant to speak up because Sony itself has kept its public self-defense to a minimum.

Representatives for Walt Disney, Paramount Pictures, Universal Pictures, 20th Century Fox, Warner Bros. and Sony Pictures either declined to comment or did not respond to queries.

Privately, some Sony executives have expressed bewilderment and resentment at the public silence of the company’s peers. One of the studio’s executives used the following analogy: Imagine a cul-de-sac where, when one house erupts in flames, the neighbors never come outside to help.

A general reluctance to speak out against the free use of Sony’s stolen secrets is fueled, at least in part, by the fear that attention will swing to any vocal defender, either in the form of hacking or in unwanted media attention.

Indeed, there is a tacit acknowledgment that, so far, virtually nothing in Sony’s stolen emails looks different from what would likely surface if the hackers hit another studio.

At Warner, for instance, legal and administrative fights with film magnate Harvey Weinstein have already provided a public glimpse of Hollywood’s bare-knuckle negotiating tactics, and a brawl over corporate succession aired severe tensions between top executives and the departed movie chief Jeff Robinov.

So the assumption is that almost every institution here has substantial dirty laundry – and some perhaps a great deal more than Sony, which has been relatively free of public scandal since the 1990s, when its executives and stars were tied to the Hollywood madam Heidi Fleiss.

When the industry came under scrutiny after mass shootings in Newtown, Connecticut, and in a Colorado movie theater that was playing Warner’s "The Dark Knight Rises," Hollywood players and Dodd convened a White House summit to ease the situation with promises of fresh research into any connection between media and violence. Concerted action of that sort was more typical in the decades when Jack Valenti, a notably proactive leader, ran the motion picture association, and Lew Wasserman, as the chief of MCA Inc., which owned Universal, kept a careful watch over situations that were likely to damage the industry.

On Thursday, nearly three weeks after the attack on Sony’s systems, a Sony spokeswoman could point to only a handful of major public voices: Douglas Wick, a producer who was long based at Sony; Judd Apatow; and directors Philip Lord and Seth Grahame-Smith, who directed Sony’s "22 Jump Street." Writing in The Hollywood Reporter or on social media, the four men expressed allegiance to Amy Pascal, and Apatow lashed out at media outlets trafficking in stolen documents.

Aaron Sorkin, who has done business at Sony, added his support Friday, even as actress Lisa Kudrow, in a Huffington Post interview, lectured Sony executives about choosing their online words more carefully to avoid embarrassing disclosures.

Boies, for his part, had severe words for news organizations that continued to mine Sony’s data. "If you don’t comply with this request," he wrote, Sony "will have no choice but to hold you responsible for any damage or loss arising from such use or dissemination by you."

Kurt Opsahl, deputy general counsel for the Electronic Frontier Foundation, voiced doubt that media outlets could be forced to avoid such material, even if it was illegally obtained by a third party, given court precedent. "It is unfortunate that Sony got hacked, and lost control over its internal information," Opsahl said in an email. "But the solution is not to muzzle the press."

So far, the data files have been periodically loaded onto anonymous posting sites like Pastebin. Hackers have then notified reporters and others by email. Those who were curious could then download the files and sift through them to obtain information.

The combining of entertainment and media properties under one corporate roof appears to be playing a role in Hollywood’s reluctance to involve itself in the disclosures: Sony is the only entertainment company without some kind of news operation somewhere in the corporate mix. Time Warner owns both Warner Bros. and TMZ.com, for instance. The Walt Disney Co. owns ABC News and is a co-owner with Univision Communications of the more tabloid-oriented Fusion, which was among the first outlets to publish reports based on the hacked information. A Fusion spokesman said he was unaware of having received a letter and did not comment further.

Michael Cieply and Brooks Barnes, New York Times

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