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American District Telegraph Co

American D

Active Patents

0

Total Holdings

4

Patent Holdings

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Patent No.	Title	Status	Filing Date	Grant Date	Claims	Actions
US3444544A	Light modulated intrusion detection system	Expired / Lapsed	1965-07-19	1969-05-13	0	Details
US2227147A	Photoelectric burglar alarm system	Expired / Lapsed	1938-03-24	1940-12-31	0	Details
US2116462A	Automatic electric signal circuit	Expired / Lapsed	1931-05-22	1938-05-03	0	Details
US1331151A	Recording system and apparatus	Expired / Lapsed	1917-01-27	1920-02-17	0	Details