CStone Pharmaceuticals (HKG:2616) Chief Executive Officer Jianxin Yang increased his holding in the drug company by 560,000 shares, according to a Wednesday filing with the Hong Kong bourse.

Yang purchased the shares at a price ranging from HK$2.26 to HK$3.29 apiece, the filing said.

Since beginning in his role as CEO, Yang has bought 10,359,000 shares, or 5.46% of the total shareholding of CStone.