Kathleen M. "Katie" O'Sullivan

4.6 (39 reviews )

Seattle Washington United States

Appellate Practice Bet-the-Company Litigation Commercial Litigation

Recognized in Best Attorney USA since 2009

206-359-8000 Website

About Kathleen

Kathleen M. O'Sullivan is a top attorney recognized by Best Lawyers in the practice area(s) of Appellate Practice, Bet-the-Company Litigation and Commercial Litigation.Kathleen M., who practices law in Seattle, Washington, has been recognized since 2009. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Kathleen M. is held by other top lawyers in the same geographic and legal practice area.

Kathleen M. O'Sullivan is a top attorney recognized by Best Lawyers in the practice area(s) of Appellate Practice, Bet-the-Company Litigation and Commercial Litigation.

Kathleen M., who practices law in Seattle, Washington, has been recognized since 2009. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Kathleen M. is held by other top lawyers in the same geographic and legal practice area.

Practice Areas

Appellate Practice

Bet-the-Company Litigation

Commercial Litigation

Case History

Education

Georgetown University

Yale University

Professional Affiliations

Awards & Recognition

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Reviews

4.6 / 5

39 Reviews

1,050 Profile Views

Clyde Reilly

Jan 31, 2026

Top notch experts in Seattle - Kathleen M. "Katie" O'Sullivan is by far the best lawyer I've ever had

Best lawyer for Appellate Practice law in Seattle. Period. I've seen others, but Kathleen M. "Katie" O'Sullivan is on another level. They truly care about their clients and work hard to get the best r...

Kathy Gusikowski

Jan 31, 2026

Kathleen M. "Katie" O'Sullivan did a great job handling my complex Appellate Practice law case from start to finish

I appreciate how Kathleen M. "Katie" O'Sullivan handled my case. No fluff, just straight to the point and very effective representation for my Appellate Practice law matter. They are obviously very ex...

Conrad Glover

Jan 31, 2026

Great people who truly care at Kathleen M. "Katie" O'Sullivan - the best legal team in Washington

Everyone at Kathleen M. "Katie" O'Sullivan's office in Seattle was so nice and helpful. They made a tough situation a lot easier to deal with by being so patient and explaining everything clearly. I n...

Sheila Harvey

Jan 31, 2026

The absolute best in Seattle for Appellate Practice law - and I mean that from the bottom of my heart

Short and sweet: Kathleen M. "Katie" O'Sullivan is the real deal and a true professional in the field of Appellate Practice law. If you're in Seattle and need help with your legal issues, call them im...

Gary Goyette

Jan 31, 2026

Outstanding experience with Kathleen M. "Katie" O'Sullivan in Seattle - truly the best legal team

I didn't think I'd find such a good lawyer in Washington, but here we are and I am thoroughly impressed. Kathleen M. "Katie" O'Sullivan is just awesome and exceeded all my expectations. No complaints...

Kathleen M. "Katie" O'Sullivan

About Kathleen