The Securities and Exchange Commission has subpoenaed the stock-trading records of more than one dozen current and former Delphi Corp. employees, including four former finance executives, reported the Detroit News.

The finance executives include chief financial officer Alan Dawes, controller Paul Free, treasurer Pam Geller, and vice president of treasury, mergers and acquisitions John Blahnik, according to the newspaper. All four left the company since March.

Another eight current and former employees have received subpoenas for trading records dating back to Delphi’s 1999 spin-off from General Motors Corp. in 1999, added the News, citing people familiar with the investigation.

The embattled auto-parts giant is already desperately trying to stave off bankruptcy; according to Bloomberg, Delphi is seeking a $6 billion bailout package from GM. It is also the subject of investigations involving the Federal Bureau of Investigation, the Department of Justice, and the United States Postal Inspectors in addition to the SEC.

According to the News, it is unclear what prompted the latest subpoenas or what the SEC is investigating. The paper added that Delphi representatives declined to comment.