Patent classifications
H
ELECTRICITY
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H04
ELECTRIC COMMUNICATION TECHNIQUE
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H04M
TELEPHONIC COMMUNICATION
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3/00
Automatic or semi-automatic exchanges
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H04M3/42
Systems providing special services or facilities to subscribers
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H04M3/436
Arrangements for screening incoming calls; , i.e. evaluating the characteristics of a call before deciding whether to answer it
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H04M3/4365
based on information specified by the calling party, e.g. priority or subject
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