Nasdaq, Bats Sites Attacked as Trading Systems Unaffected

Nasdaq OMX Group Inc. (NDAQ) and Bats Global Markets Inc., two of the three biggest operators of U.S. stock exchanges, said access to their websites was disrupted by attacks that flooded their systems with traffic.

Both companies said their trading systems were unaffected. Joseph Christinat, a spokesman for New York-based Nasdaq OMX, and Stacie Fleming of Lenexa, Kansas-based Bats confirmed the outages. For Nasdaq, its main Web page as well as, a market information site, were disrupted.

NYSE Euronext (NYX), owner of the New York Stock Exchange, didn’t experience an outage, according to Richard Adamonis, a spokesman. Nor did Direct Edge Holdings Inc., the fourth-largest U.S. exchange owner, said Jim Gorman, a spokesman.

Nasdaq OMX disclosed an intrusion last year involving “suspicious” files on its Directors Desk system, which lets corporate board members communicate and share information. The National Security Agency, the top U.S. electronic intelligence service, joined a probe of the 2010 attack, people familiar with the investigation said in March.

To contact the reporter on this story: Nina Mehta in New York at

To contact the editor responsible for this story: Nick Baker at

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