The hackers stole passwords, names, addresses, Social Security numbers, and drivers license numbers of legitimate customers of the company's Seisint division. Seisint collects data on individuals that law enforcement agencies and private companies use for debt recovery, fraud detection, and other services.
Here is a press release issued by Lexis-Nexis regarding the investigation into the privacy breach. Lexis-Nexis acquired Seisint in September 2004 for $775 Million. Due to the privacy breach I suspect that the price of the acquisition just went up substantially.
This is the second high profile breach of confidential health data in as many weeks. In mid February there was a report of a breach of 145,000 individuals confidential information at ChoicePoint. For more information on this particular breach read the following article from PCWorld. Interesting on March 4, 2005 ChoicePoint announced its decision to exit those lines of its business which involve the sale of confidential and sensitive consumer data.