Abraham Lincoln holds the distinction of being the only US President to have obtained a patent.

The US Patent Office issued Patent No. 6,469 for “Buoying Vessels Over Shoals” on May 22, 1849. Lincoln conceived the idea of inventing a mechanism that would lift a boat over shoals and obstructions when on two different occasions the boat on which he traveled got hung up on obstructions.

This device was composed of large bellows attached to the sides of a boat that was expandable due to air chambers. His successful patent application led to his drafting and delivering two lectures on the subject of patents while he was President. As an attorney, Lincoln was familiar with the patent application process as well as patent lawsuit proceedings. Among his notable patent law experiences was litigation over the mechanical reaper.

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