According to Reuters, the sale of the shares took place over two separate trades during the last seven days.
Neither party has confirmed why the sale of the stock, which represents a portion of the total amount held by CIC, has gone ahead.
However, reports suggest that CIC may have undertaken the sale as part of a bid to reduce its holding in the investment bank below ten per cent.
Under US legislation, an organisation which holds a stake larger than this could be subject to further disclosures and regulatory scrutiny.
CIC began investing in Morgan Stanley in 2007 after it acquired a 9.86 per cent stake in the firm in exchange for $5.6 billion.
John Mack, former chief executive officer and current chairman of Morgan Stanley was appointed as a financial advisor to CIC earlier in the year.
Joseph Yam, former head of Hong Kongâs Monetary Authority, is also to join CIC in a similar capacity.
By Jim Ottewill