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Patents Grantslast 30 patents

Information Patent Grant
Exclusion system for a key telephone system
- Patent number 4,158,111
- Issue date Jun 12, 1979
- International Telephone & Telegraph Corp.
- Bruce R. Saxon
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
3173128
- Patent number 3,173,128
- Issue date Mar 9, 1965
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
2850579
- Patent number 2,850,579
- Issue date Sep 2, 1958
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
2236797
- Patent number 2,236,797
- Issue date Apr 1, 1941
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
2201358
- Patent number 2,201,358
- Issue date May 21, 1940
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
2183839
- Patent number 2,183,839
- Issue date Dec 19, 1939
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
1942404
- Patent number 1,942,404
- Issue date Jan 9, 1934
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
1930921
- Patent number 1,930,921
- Issue date Oct 17, 1933
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
1896315
- Patent number 1,896,315
- Issue date Feb 7, 1933
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
1783295
- Patent number 1,783,295
- Issue date Dec 2, 1930
- H04 - ELECTRIC COMMUNICATION TECHNIQUE