On January 24, 2018, with respect to an Invalidation Request filed by Rohm and Haas Electronic Materials CMP Holding CO., LTD. against invention patent No. 00811638.5 of Cabot Microelectronics Corporation, Reexamination Board of SIPO issued a Invalidation Decision to declare the amended Claims of this invention patent valid.

Headquartered in Illinois, USA, Cabot Microelectronics Corporation is the world’s leading supplier of chemical mechanical planarization slurries (CMP) and the second largest CMP pads supplier to the semiconductor industry. Their products are used to level, smooth and remove excess material from the multiple layers deposited upon silicon wafers in the production of semiconductor devices. Cabot Microelectronics Corporation possesses the above Chinese patent which seeks protection for CHEMICAL MECHANICAL POLISHING SYSTEMS AND METHODS FOR THEIR USE.

The issues of the case lie: 
(1) whether the amendment to an independent clam based on a part of features in a dependent claim complies with the relevant prescription in the Guidelines For Examination; and
(2) whether it shall analyze a function played by a distinguishing feature in a technical solution from the point of view of inventive concept when evaluating inventive step. 

During the invalidation proceeding, on behalf of Cabot Microelectronics Corporation, Liu Shen successfully argued that (1) the part of features in the dependent claim is an independent technical feature instead of a partial technical feature, and further restricting the independent claim based on the feature complies with the relevant prescription in the Guidelines For Examination; and (2) inventive concepts of the present patent and the prior art are totally different, some components seem identical but play different functions in the technical solutions of the present patent and the prior art, and the prior art does not give any technical teaching, either, and thus the claims of the present patent possess inventiveness. The Board accepted our arguments and declared the all amended Claims of this invention patent valid.  

Ms. Li Song, Mr. Nican Jin, Mr. Chengbin Zhan, and Mr. Xiaofei Zhang of Liu, Shen & Associates represented the patentee of Cabot Microelectronics Corporation for this case.