After the trial sale of new electric tricycles which were independently researched and developed by JIANGSU KINGBON VEHICLE CO., LTD in Jiangsu Province in 2014, Tianchang Zhang, the company’s research and development staff, applied for an utility model patent to the State Patent Office. After leaving the company, he initiated a lawsuit against JIANGSU KINGBON VEHICLE CO., LTD in violation of his patent right. Shnfan Law Firm, as the defendant agency of JIANGSU KINGBON VEHICLE CO., LTD, affirmed Zhang Fanchang's involvement in the research and development of new products during the opening defense. However, according to the Patent Law: if the company continues to produce only within the scope of the original production scale, it can claim that it will not infringe upon his patent right on the grounds of having prior rights. Before Zhang applied for the patent, new product had already been tested and sold as existing technology on the market, and did not infringe the patent right. Subsequently, Shnfan Law Firm requested patent reexamination procedure to State patent Office to declare that the patent is invalid on the ground that the patent is lack of novelty. After examination by the Trademark Office, if the patent right is declared invalid, the patent right will not be deemed to have existed since the beginning; JIANGSU KINGBON VEHICLE CO., LTD does not infringe the patent right and does not need to pay compensation.