About our firm

Siderius Lonergan & Martin, LLP was founded in 1959 by Ray Siderius, Charles Lonergan Jr. and the late Washington State Court of Appeals Judge T. Patrick Corbett. Today the firm continues to enjoy a small collegial atmosphere. We have been given the highest AV rating for skill and integrity by Martindale Hubbell. Our practice areas include general and complex litigation, business and commercial law, banking and credit union law, criminal defense, real estate, and estate planning.

Our experienced attorneys handle matters ranging from small business issues to major class action litigation. In Hemphill v. Department of Revenue, we prevailed in a class action challenge to the Department of Revenue’s collection of estate taxes that resulted in the highest tax refund in Washington state history (over $150 million).

Our attorneys and staff have fulfilling lives both inside and outside time spent in the office or courtroom. Whether coaching youth and Special Olympic sports, tutoring underprivileged children, providing volunteer legal services or serving on boards of non-profit organizations, members of the firm are committed to giving back to the community.

Our offices are in the Logan Building in downtown Seattle.
Map of our location. Directions to our offices.