Few plaintiffs have gone after companies’ outside lawyers in backdating lawsuits. But a new derivative case against directors and officers at Brocade Communications Systems Inc. also targets the company’s law firm, Wilson Sonsini Goodrich & Rosati. Filed April 18 in Northern District federal court by a small San Diego firm, Johnson Bottini, the suit accuses Wilson Sonsini of legal malpractice for allegedly blessing backdating at Brocade, a company that saw two of its former executives convicted of criminal charges.

In particular, the plaintiff alleges that the firm signed off on a part-time program for new Brocade hires that was really set up to grant stock options for the new employees at low points. The complaint also claims that Wilson Sonsini gave bad legal advice on a settlement proposal that didn’t give enough to Brocade in another derivative case.