This paper deals with necessary knowledge about copyright law, and inaddition related important ethics which all researchers have to learn. Atfirst, it explains the outlines of Japanese Copyright Act of 1970, andfollowing revised acts. Researchers never fail to understand the realmeaning of legal citation doctrine. They necessarily should make sense ofthe way to lawfully and ethically reuse their own academic papers. Whenthey are working at national laboratories, or famous universities, they hadbetter know something about trademark, besides patent system. Thispaper also tells about what authorship ought to be. And other topics, forexample self-archiving, institutional repositories, creative commons license,and the usage of copyright-free illustrations are discussed. This paper isdedicated to young generation researchers including my students.