Winston & Strawn LLP acts on behalf of a broad array of clients in both litigation and administrative procedures, with experience in audits, appeals, and internal investigations. Co-leading the team are James Mastracchio, who has a strong track record in both civil and criminal tax controversy, and Susan Seabrook, who is noted for her strength in complex multijurisdictional matters. New York lawyer Karl Kurzatkowski has key expertise in the insurance industry and provides support for numerous prominent clients in this area, while Zachary Weit has experience advising clients in the nonprofit sector. Unless otherwise mentioned, all recommended lawyers are based in Washington DC.

Legal 500 Editorial commentary

Testimonials

Collated independently by Legal 500 research team.

  • ‘Unique strength in the area of representing financial institutions, including insurance companies; controversy team understands the non-tax regulatory issues facing its clients and this helps them resolve tax issues.’

  • ‘Susan Seabrook has deep knowledge of the insurance industry from both inside and outside of the government. Karl Kurzatkowski is a strong contributor to the team.’

Key clients

  • Norwich Commercial Group, Inc.
  • Government of the U.S. Virgin Islands

Work highlights

  • Advised a multinational insurance company in connection with an IRS-proposed adjustment well in excess of $1b relating to a contentious industry issue.
  • Acted for the Government of the US Virgin Islands in a series of related tax shelter cases against residents of the Virgin Islands before the Third Circuit Court of Appeals.
  • Represented a multinational financial services company in a Large Corporate Compliance audit by the IRS.

Practice head

The lawyer(s) leading their teams.

James Mastracchio, Susan Seabrook

Other key lawyers

Zachary Weit, Karl Kurzatkowski