Stinson Leonard Street will soon merge its St. Louis area branch with intellectual property firm Senniger Powers as Stinson continues to expand its offices.

Stinson, one of the largest law firms in the Twin Cities, recently announced the change that will grow its office in Clayton, Mo., near St. Louis, to 75 attorneys and expand the firm’s intellectual property services. The merger will take effect in October.

“Senniger Powers has a long-standing history as a prominent intellectual property firm in the St. Louis region and beyond,” said Mark Hinderks, Stinson’s managing partner, in a statement. “Their attorneys and patent agents offer the business community a robust combination of scientific, technical and legal experience to deliver effective solutions to achieve clients’ business objectives.”

Senniger Powers primarily focuses on the preparation and prosecution of patents, copyrights and trademarks in industries such as life sciences, pharmaceuticals, manufacturing and software. Many of the firm’s attorneys are engineers or scientists.

“We are excited for the opportunity to grow our resources in the St. Louis market and to expand our national reach,” said Kurt James, managing partner at Senniger Powers, in a statement.

Senniger Powers will move from its downtown St. Louis office to Stinson’s Clayton offices.

Stinson is a full-service law firm with distributed headquarters in both Minneapolis and Kansas City and nearly 500 attorneys among its 15 locations across the country.

The Clayton office is Stinson’s latest expansion. In June, Stinson added offices in Dallas and Denver.