MICHAEL WARDEN formerly served as co-leader of Sidley’s Accountants and Professional Liability practice and has been involved in some of the most significant financial and accounting matters over the last 30 years. He represents accounting firms and their partners and corporations and their officers in SEC investigations and enforcement actions, internal investigations and in securities, class action, derivative, and other litigation. Mike also regularly represents audit firms and their partners in PCAOB investigations. Mike has tried cases before judges, juries, arbitrators, and SEC administrative law judges. He also has represented audit committees in investigations. His matters have involved a broad range of accounting, financial reporting, and disclosure issues, including revenue recognition, auditor independence, pharmaceutical accounting issues, impairment issues, tax and legal accruals, accounting fraud, auditing issues, and financial restatements.
Benchmark Litigation recognized Mike as a “Litigation Star” for his work in White Collar Crime, Commercial Litigation, and Professional Liability (2023–2025).
Recent and Pending Matters
- Represented non-U.S. Big Four accounting firm in investor claim in New York Supreme Court
- Represented chief financial officer of public company in SEC investigation regarding legal accruals
- Obtained defense verdict for Fortune 50 company in bench trial in U.S. District Court
- Obtained dismissal for partners of non-U.S. Big Four accounting firm in New York Supreme Court
- Representing multiple U.S. and non-U.S. Big Four firms in multiple SEC and PCAOB investigations
- Represented partner of Big Four firm in PCAOB investigation that was settled without suspension
- Obtained dismissal with prejudice of securities fraud class action in S.D.N.Y. against Big Four coordinating entity of network firms
SEC, PCAOB, and Other Accounting Matters:
- Represented Big Four accounting firms and partners in multiple formal and informal PCAOB investigations without charges
- Represented non-U.S. Big Four firm in settled SEC investigation involving independence issues
- Represented partners of multiple non-U.S. Big Four firms in settled PCAOB investigations
- Represented multiple chief financial officers of public companies in separate SEC investigations with no charges
- Represented two Big Four accounting firms in SEC and DOJ investigations regarding stock option backdating at their clients’ firms. Obtained dismissal of securities fraud class action claims against accounting firms
- Represented Big Four accounting firm in subprime-related SEC investigation
- Represented Big Four accounting firm in malpractice claim by former client regarding fraud at client’s overseas subsidiary, in malpractice claim by bankruptcy trustee, and in actions brought by the Florida Department of Insurance on behalf of insolvent insurance companies
- Represented major retailer in settled SEC enforcement action regarding vendor allowance payments
- Represented professional services firm in DOJ and Inspector General investigations regarding billing practices
- Represented accounting firm partner in civil litigation and DOJ and SEC investigations regarding Enron
- Conducted internal investigations for various clients, including retailers and professional services firms
Additional Trial Experience:
- Trial counsel for China Big Four accounting firm in three-week hearing before SEC ALJ regarding China accounting firms’ production of working papers to the SEC
- Trial counsel for Fortune 50 company in securities fraud class action before a jury in Trenton, N.J., in which the class sought billions of dollars in damages. The case settled on favorable terms after three weeks of trial
- Trial counsel for Big Four accounting firm in jury trial in the S.D.N.Y. Former client brought malpractice claims based on rogue trading in client’s arbitrage strategies resulting in losses of US$137 million. Jury returned a defense verdict
- Trial counsel for Northern Virginia public technology company in arbitration hearing in which former officer brought employment and retaliation claims and the company brought claims for theft of trade secrets. Company prevailed on all claims
- Trial counsel for family-owned business and officers in breach of fiduciary duty and contract claims in what was then the longest civil jury trial in D.C. Superior Court
Civil Securities Fraud and Other Representative Matters:
- Represented audit committees in multiple investigations regarding auditor independence and tax and disclosures issues in merger
- Obtained dismissal with prejudice on behalf of Virginia public corporation in shareholder derivative action in Fairfax County Circuit Court
- Represented officers in securities fraud class action in In re NII Holdings, Inc. Sec. Litig. (E.D. Va.)
- Obtained dismissal with prejudice on behalf of China Big Four accounting firm in two separate S.D.N.Y. securities class actions
- Represented public company in securities fraud class action In re Optical Cable Corp. Sec. Litig. (W.D. Va.)
- Represented company and officers in securities fraud class action in In re PSINet Inc. Sec. Litig. (E.D. Va.) Case settled on favorable terms during a two-day mediation
- Represented accounting firm in securities fraud class action In re Orbital Sciences Sec. Litig. (E.D. Va.)