The explanations of both terms are accurate. However, as far as this case is concerned, Factory B’s defense is not tenable. Factory B made the necessary preparations for production in November 2000, which was after Factory A’s patent application date (August 2000), so it did not meet the provisions of the right of prior use. Factory B's production and sales activities since June 2001 constitute infringement.
C constitutes infringement because of its sales behavior.