Court Finds that Invalid Disclaimers Invalidates the Claims.

Shmuel Hershkovitz, Paradox Security Systems Ltd. and Pinhas Shpater v. Tyco Safety Products Canada Ltd.

This decision underscores the importance of filing proper disclaimers to patent claims. Disclaimers may be filed with the patent office by a patentee after the issuance of a patent to unilaterally renounce or disclaim those portions of the claimed invention that were inadvertently included within the scope of the claims as a result of mistake, accident or inadvertence. Disclaimers therefore have the effect of narrowing the scope of the claims (i.e. the area where competitors may not tread). Disclaimers that attempt to broaden the scope of a claim are invalid.

In the present case, soon after the issuance on October 5, 1999 of Canadian patent number 2,169,670 (the '670 patent) relating to telephone line couplers used to connect electronic equipment to phone lines while providing electrical isolation, the appellant patentee Paradox Security Systems Ltd. (Paradox)