William O’Neil
Partner
Managing Partner, Chicago
Bill is the managing partner of Winston’s Chicago office. He concentrates his practice on high-stakes trial work. An adept problem solver, Bill serves as a strategic advisor to some of the nation’s largest corporations and private equity funds.
Key Matters
M&A Litigation
A significant portion of Bill’s practice involves representing strategic acquirers, private equity funds, and their portfolio companies. Bill frequently represents buyers and sellers in post-closing disputes, including working-capital, indemnity, R&W insurance, and fraud claims.
Bill has recovered hundreds of millions of dollars in post-closing judgments and settlements for aggrieved buyers in M&A disputes.
More than a dozen private equity funds have retained Bill to handle these disputes for dozens of portfolio companies; often where another law firm handled the underlying transaction. He brings a practical, business-minded approach to contentious disputes and he is frequently praised by his clients for the depth of his understanding of M&A transactions.
Bill represents numerous public company clients in corporate governance litigation, shareholder strike suits, and internal investigations. He has been retained by corporate boards and independent committees to bring impartial advice to delicate, complicated, and often crisis-level scenarios.
Complex Commercial Litigation
Beyond the M&A arena, Bill also handles a wide range of business disputes with customers, vendors, and suppliers. He has represented dozens of Fortune 500 companies in disputes ranging from routine to high-stakes, “bet-the-company” litigation. Bill is frequently called upon to provide risk-management and litigation-avoidance advice to his clients.
Non-Compete Litigation
Bill represents corporations in non-compete litigation adverse to senior executives and their new employers. Bill has handled numerous “corporate-raiding” cases where two major corporations were pitted against each other in a dispute over human capital.
Pro Bono
Bill’s pro bono cases have included representing a prison inmate in a successful appeal before the Seventh Circuit Court of Appeals that resulted in new law in the circuit, the court’s reversal of its own prior precedent, and the reversal of the defendant’s conviction.
Bill O’Neil is best-in-class in terms of business partnership, communication and service. Highly recommended.
The Legal 500 US
Bill O’Neil is an outstanding attorney who helps make complex issues easier to understand and fights like a badger when we need it.
The Legal 500 US