Bloomberg dug through 60,000 emails that the loosely affiliated group of activists known as Anonymous stole from the security firm HBGary and came up with some surprising revelations about the prevalence of cyberattacks against American corporations. It turns out that several large companies have been subject to attacks like the one that Google disclosed in January 2010.

DuPont Co., Johnson & Johnson and General Electric Co. (GE) are among more than a dozen previously unidentified companies whose networks were broken into in the past two years by hackers intent on stealing some of their most valuable assets, confidential e-mails show.

Some of the attacks mirror the one against Google Inc. (GOOG), which said in January 2010 that it had lost intellectual property assets to hackers based in China and that about 20 other companies were victims of the same kind of intrusions.

The attacks are discussed in about 60,000 confidential e- mails that HBGary, Inc., a cyber-security firm hired by some of the companies, said were stolen from it on Feb. 6 and posted on the Internet by a group of hacker-activists known as Anonymous. Companies attacked include Walt Disney Co. (DIS), Sony Corp. (6758), Johnson & Johnson, and GE, the e-mails show.

Read the full story at Bloomberg.

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