Apparatus and process for the delivery of doses of one or more gases to the respiratory tract of a user

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

• Filed July 21, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 21, 2013.
• A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 21, 2015.
• We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.