Inventors, patent applicants, and patent assignees should carefully consider who the actual inventors of their patents are, or they may risk losing their patent rights altogether.

In 2023, the Federal Court found that the inventor listed on Canadian Patent No. 2,624,834 (the ‘834 Patent) had likely learned the ideas behind the inventive concept of the patent from one of his subordinates while working at Genesis International Oilfield Services Inc. After learning of the inventive concept, that “inventor”, John Ewanek, moved to a new company, which filed the ‘834 Patent with Ewanek listed as the sole inventor. The ‘834 Patent was later purchased by Canadian Energy Services L.P.

The Federal Court declared that Ewanek’s subordinate at Genesis was the actual inventor of the ‘834 Patent and that the successor company to Genesis was therefore the actual owner of the ‘834 patent.

Key evidence at the trial were the logbooks and records kept by the subordinate, which substantiated the fact that he was the actual inventor.

Canadian Energy Services unsuccessfully appealed the Federal Court decision to the Federal Court of Appeal, and has now sought leave to appeal to the Supreme Court of Canada. Litigating inventorship questions before the courts can be costly, which could have been avoided by carefully considering inventorship from the outset of filing or by conducting due diligence reviews of inventorship when purchasing a patent.