• Technology trends
  • Patent search
  • Sign In
  • Sign Up
Patent classifications
H
ELECTRICITY
Load children
H04
ELECTRIC COMMUNICATION TECHNIQUE
Load children
H04M
TELEPHONIC COMMUNICATION
Load children
3/00
Automatic or semi-automatic exchanges
Load children Filter patents View analytics View as hierarchy
H04M3/42
Systems providing special services or facilities to subscribers
Load children Filter patents View analytics View as hierarchy
H04M3/42025
Calling or Called party identification service
Load children Filter patents View analytics View as hierarchy
H04M3/42034
Calling party identification service
Load children Filter patents View analytics View as hierarchy
H04M3/42042
Notifying the called party of information on the calling party
Load children Filter patents View analytics View as hierarchy