What happens to a patent when it expires?
it becomes the property of the state
ownership rights are inherited
the patent is licensed
It becomes public domain
A patent allows you, and only you, to profit from your genius when you invent something new. No one else can manufacture or sell your invention unless you give permission. When a patent expires,  anyone can copy your idea and market it. It becomes public domain  
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Answers by country
it becomes the property of the state
ownership rights are inherited
the patent is licensed
It becomes public domain
answers
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