The Collaborative International Dictionary of English v.0.48:

Patentee \Pat`ent*ee"\, n.
   One to whom a grant is made, or a privilege secured, by
   patent. --Bacon.
   [1913 Webster]

WordNet (r) 3.0 (2006):

patentee
    n 1: the inventor to whom a patent is issued

Bouvier's Law Dictionary, Revised 6th Ed (1856):

PATENTEE. He to whom a patent has been granted. The term is usually applied
to one who has obtained letters-patent for a new invention.
     2. His rights are, 1. To make, sell and enjoy the profits, during the
existence, of his rights, of the invention or discovery patented. 2. To
recover damages for a violation of such rights. 3. To have an injunction to
prevent any infringement of such rights.
     3. His duties are to supply the public, upon reasonable terms, with the
thing patented.