John T. A. Rosenthal Joins Klinedinst Los Angeles as Senior Counsel

John T. A. Rosenthal has joined the Klinedinst Los Angeles office as Senior Counsel. An experienced business attorney, Mr. Rosenthal brings his legal skills to the firm’s Business and Commercial Litigation, Intellectual Property, and Professional Liability groups.

LOS ANGELES, CALIFORNIA – Klinedinst is pleased to announce John T. A. Rosenthal has joined the Los Angeles office as Senior Counsel. Mr. Rosenthal began his career in 2000 as a litigator for a large firm in California.  He then moved to New York and continued practicing in Manhattan for the same large firm. He joins Klinedinst after a successful career at a boutique business law firm in White Plains, New York.

photo of John T. A. Rosenthal
John T. A. Rosenthal

Mr. Rosenthal has significant experience in representing clients in a wide variety of litigation matters in state and federal courts across the country, as well as before various regulatory bodies, including the U.S. Patent and Trademark Office (USPTO), the U.S. Copyright Office, and the Federal Trade Commission (FTC).

An accomplished speaker, Mr. Rosenthal has assisted clients in developing, managing, protecting and leveraging their intellectual property portfolios, including the negotiation and crafting of license agreements.

“We welcome John back to the West Coast and are extremely excited to add him to the Los Angeles team,” said Jeffrey Groendal, Managing Shareholder of Klinedinst Los Angeles. “John’s experience and sophistication in business and intellectual property matters are ideal for our client-base and, in particular, for the dynamic business and entertainment climate in LA. We expect John to thrive here. He will be a terrific asset to our team, and a true champion for the rights of our clients.”

In addition to being licensed in California, Mr. Rosenthal is licensed in New York, and was selected for inclusion in New York Metro Super Lawyers® from 2013 to 2018.

Klinedinst PC is pleased to welcome Mr. Rosenthal to the firm. To learn more about Mr. Rosenthal, please visit:

About Klinedinst

Klinedinst is the go-to firm for clients looking for litigation, trial experience, transactional representation, and legal counsel.  The firm’s offices in Los AngelesSacramentoSan DiegoSanta Ana, and Seattle service the entire West Coast. What sets Klinedinst apart is the relationship our attorneys foster with each and every client. Klinedinst lawyers are indispensable strategic partners to business leaders, helping to achieve business objectives and create proactive solutions to resolve the many legal challenges that businesses are confronted with every day.  Whether vigorously advocating for business clients in court, or guiding business transactions and negotiations, Klinedinst is the trusted legal advisor to have by your side.