Since 2010, the Patent Re-examination Board (PRB) has published the top 10 patent invalidation cases of the year in April of each year. The selection criteria are high social concern, significant impact on the related industry, or involve difficult legal issues and important examination criteria. Below is one of the top 10 cases that discusses what is considered allowable claim scope around sequences. It is well known that China has strict requirements when it comes to adequate written description and support in the specification. Chinese Patent Law Article 26(4) says that “all claims must be supported by the description and shall define the extent of the patent protection sought for…