The United States has charged four men with stealing $100 million worth of intellectual property from Microsoft Corporation, Epic Games Inc., Valve Corporation, Zombie Studios and the U.S. Army.

The men, all between the ages of 18 and 28, allegedly used sophisticated methods to break into the company's systems to steal games before they were released to the public. In the case of the Army, the hackers allegedly stole Apache helicopter simulator software developed by a video game manufacturer.

The Guardian reports:

"'These were extremely sophisticated hackers.... Don't be fooled by their ages,' assistant US attorney Ed McAndrew said after a court hearing on Tuesday. ..."David Pokora, 22, of Mississauga, Ontario, and Sanadodeh Nesheiwat, 28, of Washington, New Jersey, each pleaded guilty to a single count of conspiracy to commit computer fraud and copyright infringement. They face up to five years in prison when sentenced in January."Prosecutors said the two men were part of a small group of gaming enthusiasts that called itself the Xbox Underground."An 18-count indictment that was returned by a grand jury in April and unsealed Tuesday also charges Nathan Leroux, 20, of Maryland, and Austin Alcala, 18, of Indiana, with participating in the conspiracy."

In a statement, the Justice Department said the hackers used SQL injection and stolen usernames and passwords to access the networks.

"Once inside the victims' computer networks, the conspirators accessed and stole unreleased software, software source code, trade secrets, copyrighted and pre-release works and other confidential and proprietary information," Justice said. "Members of the conspiracy also allegedly stole financial and other sensitive information relating to the companies – but not their customers – and certain employees of such companies."

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