On August 12, 1851, Isaac M. Singer was granted a patent for the first practical and efficient sewing machine. His sewing machine was revolutionary, having a double treadle.

Elias Howe had patented the sewing machine before Singer. So Singer paid huge settlements to Howe. However, Singer used smart business innovations like installment buying, after-sale servicing and trade-in allowances, to take a leading position the marketplace.

Sources: Todayinsci

This patent led to the first major patent war. Watch this video:

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