HONG KONG, Jan 15 (Reuters) - The world’s biggest asset manager, Blackrock Inc, sold almost all its shares in China Telecom this week at a hefty discount, stock market filings showed on Friday. China Telecom is one of 44 companies subject to a new ban on U.S. investment. BlackRock sold 818 million shares at an average of HK$1.92 each on Tuesday, according to a Friday Hong Kong exchange filing. That is 12% below Tuesday’s closing price. The filing gave no reason for the HK$1.6 billion ($206 million) sale, which reduced BlackRock’s stake in China Telecom from 6.1% to 0.2%, and BlackRock had no immediate comment.