Before the product was patented, it was released in a circle of friends. Later, he applied for a patent and sued me. Can his patent be invalidated?

1. independent research and development by riders 2. There is a factory. Four of us. Who is the patentee of the other factory? Is the patent authorized to issue certificates? If the certificate has been issued, it can be declared invalid. You must prove that the patent has been made public before the application. The publicity of friends circle, qq space, website, publicity, advertisement and periodical is called publicity. . . . There is no infringement without a certificate.