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AIzaSyB4mHJ5NPEv-XzF7P6NDYXjlkCWaeKw5bc
May 31, 2026
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Public Timelines
FAQ

Rising number of patents (200 to 4,000/year) (may 1, 1820 – mar 1, 1860)

Added to timeline:

11 Nov 2022
0
0
486

Date:

may 1, 1820
mar 1, 1860
~ 39 years