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It was a symbiotic relationship that brought together the underbelly of Wall Street and the dark reaches of the online world. From their suburban homes in the United States, dozens of rogue stock traders would send overseas hackers a shopping list of corporate news releases they wanted to get a sneak peek at before they were made public. The hackers, working from Ukraine, would then deliver how-to videos by email with instructions for gaining access to the pilfered earnings releases. In all, 32 traders and hackers reaped more than $100 million in illegal proceeds in a sophisticated and brazen scheme that is the biggest to marry the wizardry of computer hacking to old-fashioned insider trading, according to court filings made public on Tuesday. One of the men, Vitaly Korchevsky, a hedge fund manager and former Morgan Stanley employee living in a Philadelphia suburb, made $17 million in illegal profits, the indictment said. But the five-year scheme came undone Tuesday when federal prosecutors from Brooklyn and New Jersey, joined by regulators from the Securities and Exchange Commission and other law enforcement agencies, announced a series of arrests, the filing of indictments and a lawsuit against what the indictments described as a loose network of business confederates.

Early Tuesday, the authorities arrested Mr. Korchevsky, 50, at his home in Glen Mills, Pa., and four other men, in Georgia and in Brooklyn. Arrest warrants were issued for four other men. Three of them were related and had ties to Ukraine. "This is the intersection of hacking and securities fraud," Paul J. Fishman, the United States attorney for the district of New Jersey, said at a news conference in Newark. "The hackers were relentless and patient." In one indictment, federal prosecutors in New Jersey said five of the men broke into companies like Business Wire and PR Newswire over five years to steal more than 150,000 news releases being prepared by publicly traded corporations before the information was released to the public. Another company whose releases were stolen before they were made public was Marketwired. Mr. Fishman did not fault the wire services and said they had cooperated with the investigation. The stolen news releases gave the rogue traders — four of whom were charged in a separate indictment unsealed on Tuesday by prosecutors in Brooklyn — a big advantage over others in the stock market by allowing them to trade on news before it hit the wires, the authorities said. The men who used the stolen information to trade the stocks paid the hackers a flat fee or a percentage of the profits gained from the illegal trading, the S.E.C. said in a separate complaint. Read MoreThe $400 billion threat to global business The authorities said the traders seeking an illegal edge provided "shopping lists" to hackers for the kinds of news releases they wanted and the companies they wanted to trade on. The men obtained information from more than 30 companies, including Bank of America, Clorox, Caterpillar and Honeywell, the authorities said. But the traders were also deliberate. The authorities said they traded ahead of the information contained in only about 800 of the hundreds of thousands of releases they got a sneak peek at — indicating a methodical and well-timed approach to concealing their activities. In multiple instances, the men communicated via email and online chat messages, boldly stating what they were doing, the authorities said. At one point in 2012, for example, one of the defendants wrote in Russian in an online chat message, "I'm hacking prnewswire.com." In another instance, a defendant sent 96 stolen news releases to someone with a subject, in Russian, that read "fresh stuff." The email said, "If he says he does not know what this is about, tell him 'quarterly report,' " according to the indictment. The authorities monitored some of the defendants for years, the indictment said. In November 2012, it said, they seized the laptop of one of the hackers and found about 200 nonpublic news releases from PR Newswire. The people charged in the New Jersey indictment with breaking into the newswire networks were Ivan Turchynov, 27; Oleksandr Ieremenko, 24; Arkadiy Dubovoy, 51; Igor Dubovoy, 28; and Pavel Dubovoy, 28.