Law Firm Profile


We are Canadian lawyers and registered trademark agents, operating under the firm name of Warren Sinclair LLP.
We’ve registered hundreds of trademarks for our clients over the years.  We act for clients across Canada and in numerous countries around the world. We are based out of Central Alberta, Canada which is strategically located between two major urban centres, Calgary & Edmonton, including two international airports. As such, our law firm is accessible to a local market area population of 2.4 million.

Our Office

Our Office

We can assist you with all your Canadian trademark matters, including with trademark searching, preparing trademark applications, licensing Canadian trademark rights, trademark oppositions, trademark expungement (cancellation) proceedings, trademark enforcement and protection, domain name disputes and with the purchase and sale of trademarks and the goodwill of a business.

The Warren Sinclair LLP team of trademark professionals is led by Mr. Sander Gelsing, who is a lawyer, patent agent and trademark agent.  Mr. Gelsing provides representation before the Canadian Intellectual Property Office, the Trademark Opposition Board and various courts, including the Federal Court.  He has over twelve years experience in trade-mark prosecution and litigation matters.

Mr. Sander Gelsing

Mr. Sander Gelsing
Canada Trademark Attorney

A team of trademark paralegals, including Ms. Breanna Smallman and Ms. Michelle Andersen, assist Mr. Gelsing with various aspects of trademark filings, office action responses, oppositions and cancellations.

Sander also combines forces with litigation partners, such as Mr. Michael Keyes from Warren Sinclair LLP, for higher end trademark litigation and “passing-off” matters. Junior lawyers and articling students provide support during trademark opposition work, in collecting evidence and with the preparation of affidavits.

We are members of INTA (International Trademark Association) and IPIC (Intellectual Property Institute of Canada). This allows us to stay updated on the latest developments in trademark law and to network with trademark practitioners world-wide.


Client Testimonials

It is a pleasure to work with Sander Gelsing on Canadian trademark matters. He explores each matter thoroughly and provides well-explained options for the clients. He is easy to work with, and is a person of high integrity.   – Alena Herranen (U.S. Attorney)

Sander is my Canadian counterpart. I am so pleased to work with him in this capacity. Sander is detail-oriented while maintaining the highest quality standards and being cost competative. Additionally, Sander is a pleasant person with whom to do business.   – Pat Costanzo (Patent and Trademark Attorney)

Sander demonstrates a great depth of knowledge in the law surrounding registering trademarks. He and his team are very professional and his counsel is thoughtful.   – Tamara Traub (President at Westfair Properties)



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