It was a big challenge for Canon Inc., one of Japan's top camera makers, to embark on the copy machine business in the late 1960s, as the market was dominated by the U.S. giant Xerox Corp.

But Canon, now a globally known printer maker, successfully penetrated the market because it checked on all the patents owned by Xerox, carried out its own research, scrutinized products, and invented a new copying technology that did not infringe on the U.S. rival's many patents.

"The importance of patents has been brought into focus in various ways lately, but we have been aware of their significance for more than 30 years," said Nobuyoshi Tanaka, managing director and group executive of Canon's corporate intellectual property (IP) and legal headquarters.