Z:gnu-www-ja-quick-guide-gplv3--d99d4b-GPLv3 offers a reprieve for go/en

GPLv3 offers a reprieve for good behavior: if you violate the license, you'll get your rights back once you stop the violation, unless a copyright holder contacts you within 60 days. After you receive such a notice, you can have your rights fully restored if you're a first-time violator and correct the violation within 30 days. Otherwise, you can work out the issue on a case-by-case basis with the copyright holders who contacted you, and your rights will be restored afterward.