How long do patents usually last for?

10 years
20 years
40 years
60 years

The correct answer is B. 20 years.

A patent is a right granted by the government to an inventor, giving them the exclusive right to make, use, sell, and offer to sell an invention for a limited period of time in exchange for the public disclosure of the invention.

The term of a patent is 20 years from the date on which the application for the patent is filed in the United States.

Option A is incorrect because a patent typically lasts for 20 years, not 10 years.

Option C is incorrect because a patent typically lasts for 20 years, not 40 years.

Option D is incorrect because a patent typically lasts for 20 years, not 60 years.