* FILING SHOWS BLOCK TRADE OF BLUEDON INFORMATION SECURITY TECHNOLOGIES CO LTD'S 23.5 MILLION SHARES INVOLVING 211.3 MILLION YUAN ($33.65 million) ON MARCH 26 Source text in Chinese: bit.ly/2grA0v1 Further company coverage: ($1 = 6.2800 Chinese yuan renminbi) (Reporting by Hong Kong newsroom)