The Securities and Exchange Commission is investigating the accounting practices of MDC Partners, expenses of CEO Miles Nadal and third-party trading of its shares.

MDC' s stock price tanked today 31.7 percent to $19.09 on the SEC news.

The ad/PR firm is “actively cooperating with the SEC and continues to do so,” according to its statement. “We are committed to the highest standards of corporate governance and transparency, and in response to this situation have taken a number of steps to strengthen our procedures and internal controls.”

The firm formed a special committee to review controls and transactions made with Nadal, who has agreed to make a payment of $8.6M for reimbursements for medical, travel and other related expenses made from 2009 though 2014.

The company has instituted a series of financial controls to tighten procedures, including new aircraft usage and travel/entertainment policies.

Nadal earned $16.8M in 2014 compensations, which was off the $20.7M mark of the earlier year.