If at least one claim is allowed, a Notice of Allowance is issued giving the applicant a deadline for paying the government issue fee. A patent will issue a few months after the issue fee is paid. The patent covers the invention as it is described in the allowed claims. The patent term, and the ability to sue for patent infringement, does not begin until the patent issues (although an invention claimed in a published application is provisionally protected from the publication date, if a patent eventually issues).