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By Jonathan Stempel and Munsif Vengattil
NEW YORK, Feb 6 (Reuters) - Business Wire, the corporate news release distributor owned by Warren Buffett's Berkshire Hathaway Inc, on Tuesday said it has been suffering for nearly a week from a cyberattack designed to disable it.
The company said it has been experiencing a "directed and persistent" denial of service attack since Jan. 31, though customer information has not been compromised.
"Our website slowed down," said Neil Hershberg, a senior vice president at Business Wire, in a phone interview. "At no point were clients unable to get our releases to us. Our distribution network was totally unaffected by this attack."
A denial of service attack occurs when hackers flood a target with incoming messages, overwhelming its systems and making it difficult or impossible for legitimate customers to do business.
Hershberg estimated that a majority of Fortune 500 companies use Business Wire, citing an internal analysis.
He said Business Wire hopes to resolve the security issues in the "near future," with help from outside firms it has hired. Hershberg said he was unaware of involvement by law enforcement.
Berkshire did not immediately respond to a request for additional comment. It bought Business Wire, which is based in New York and San Francisco, in 2006.
The attack is not the first time that Business Wire has been targeted by hackers.
In 2015, U.S. authorities brought criminal or civil charges against more than 40 defendants over the theft of roughly 150,000 news releases from Business Wire and rivals Marketwire and PR Newswire in a 5-1/2-year period.
Authorities said traders would give hackers "shopping lists" of releases they wanted, and generated more than $100 million of illegal profit through insider trading on nonpublic information contained in the releases.
At least five criminal defendants have pleaded guilty in that case. (Reporting by Jonathan Stempel in New York and Munsif Vengattil in Bengaluru; editing by Anil D'Silva)