International Game Technology PLC reached a $500,000 settlement with federal regulators Thursday on charges that it fired an employee for raising concerns about the casino-gaming company’s accounting, in a case that marked the U.S. Securities and Exchange Commission’s second enforcement action against whistleblower retaliation.

But unlike its first whistleblower retaliation case, in which regulators also found an underlying securities violation, the SEC did not allege that International Game Technology committed any misconduct aside from firing the employee.