Attorney General Greg Abbott, accusing the company of violating state anti-spyware laws by embedding software in its CDs and media player to monitor users' habits.
The new charges brought by Abbott contend that MediaMax software used by Sony BMG to thwart illegal copying of music on CDs violated state laws because it was downloaded even if users rejected a license agreement.
"We keep discovering additional methods Sony used to deceive Texas consumers who thought they were simply buying music," Abbott said in a statement.
The original lawsuit contends that Sony BMG secretly installed copy-protection software, using XCP programs, that was extremely difficult to remove from users' computers.
Sony said it has, which feature music from 52 popular artists including Ray Charles, Frank Sinatra, Louis Armstrong and Celine Dion.
Critics have said the MediaMax software lets the company track customers' listening habits even if customers reject maker SunnComm's terms in a licensing agreement that appears upon installation.
The Texas attorney general said both the MediaMax and XCP software can put customers' computers at risk.
"Malware" was detected in a mass e-mail in November that wasand enable hackers to access people's computers by bypassing firewall protections.
Sony BMG denied the MediaMax software was hidden and said it does not collect the personal information that spyware typically does.
"We are in an ongoing dialogue with the Texas Attorney General and as part of that discussion we believe we will establish that Sony BMG has responded appropriately to the issues raised today--particularly about the MediaMax software installation," a company spokesman said in a statement.