On 17 January 1882, Leroy Firman received US Patent No. 252,576 for a “Multiple switch-board for telephone-exchanges”.
The leap was not the telephone itself but the network behind it. As subscribers multiplied, manual switching had to scale beyond a single board and a single operator.
Firman’s patent captured an exchange architecture that let several operators work from different board sections while still reaching the same lines
Often cited as the first patent focused on a telephone switchboard, it is a reminder that connectivity is an engineered system, and that system has a patent history too.
Telephone operators at a switchboard in Salt Lake City, 1907 and Anamosa, 1915.
| Country | Kind | No. | Published | Title | Download |
|---|---|---|---|---|---|
| US | Patent | 252,576 | 17.01.1882 | Multiple switch-board for telephone-exchanges |
Last updated on 18 February 2026