Final answer:
Isaac Singer did not patent the lockstitch, it was actually invented by Elias Howe and improved upon by Singer.
Step-by-step explanation:
No, Isaac Singer did not patent the lockstitch. The lockstitch sewing machine was actually invented by Elias Howe in 1846 and he was the one who patented it. Isaac Singer improved upon Howe's design and obtained a patent for his own sewing machine in 1851. While Singer's machine was significant in popularizing the use of sewing machines, he did not patent the lockstitch itself.
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