Net Asset Value(s)

7 July 2009 M&G High Income Investment Trust P.L.C. The Board of M&G High Income Investment Trust P.L.C. announce that the net asset value at 12:00 noon today was £198.0 million. Income Shares * 39.99p Capital Shares 0.00p Zero Dividend Preference Shares 60.79p Income & Growth Units 39.99p Package Units 100.78p The net asset values have been calculated on a cum-income basis, with dividends payable deducted from net assets on the ex-dividend date. Financial assets are valued on a mid-market price basis. * The ex-income NAV of each Income Shares is 38.03p. ---END OF MESSAGE--- This announcement was originally distributed by Hugin. The issuer is solely responsible for the content of this announcement.