Dorsey’s Block Sued by H&R Block Over Trademark Violation

A 65-year-old tax preparation company isn’t welcoming the new kid on the block.

H&R Block Inc. sued payments company Block Inc., formerly Square Inc., claiming a violation of its “Block” trademark. H&R Block claims San Francisco-based Block Inc., co-founded and run by former Twitter Inc. Chief Executive Officer Jack Dorsey, is a direct competitor in tax prep after agreeing to buy Credit Karma Tax last year.

“Block Inc.’s name change will deceive consumers and cause irreparable harm to Block,” H&R Block said in its complaint, filed Thursday in Kansas City, Missouri, federal court. “Consumers will mistakenly believe that ...