Two Hong Kong asset management firms have agreed to pay US$10.9 million to settle charges by the US Securities and Exchange Commission of insider trading before a bid by CNOOC for Canadian oil firm Nexen. The proposed accord, disclosed in a court filing on Monday, would add to the more than US$18 million the regulator had previously secured in settlements as part of an investigation into suspicious trading linked to the July 2012 deal. China Shenghai Investment Management and eight of its clients, including an individual named Stephen Wong, have agreed to give up nearly US$4.27 million in profits realised trading in Nexen stock. Citic Securities International Investment Management (HK), a joint venture between Citic Securities International and a company owned by China Shenghai principal James Wang, agreed to pay nearly US$6.6 million in disgorged profits and penalties. CNOOC announced in 2012 that it agreed to acquire Nexen for US$15.1 billion in what became China's biggest foreign takeover bid. Shares of Nexen climbed almost 52 per cent on that day. Five days later, though, the SEC obtained a court order seeking to freeze the assets of traders using accounts in Hong Kong and Singapore to trade in Nexen. More than US$40 million in proceeds from suspicious Nexen trading were subsequently frozen, the SEC said in the court filing on Monday, including US$15 million in alleged illegal profits. In the months that followed, defendants began reaching settlements in the case. In October 2012, Hong Kong-based Well Advantage agreed to pay more than US$14 million to settle the insider trading charges. In March, mainland businessman Ren Feng and his wife Zeng Huiyu agreed to pay US$3.3 million.