The Collaborative International Dictionary of English v.0.48:

Patent \Pat"ent\, v. t. [imp. & p. p. Patented; p. pr. & vb.
   n. Patenting.]
   To grant by patent; to make the subject of a patent; to
   secure or protect by patent; as, to patent an invention; to
   patent public lands.
   [1913 Webster]

WordNet (r) 3.0 (2006):

patented
    adj 1: (of devices and processes) protected by patent; "they are
           patented inventions"