Investec has kept its 'sell' rating for High Street department store Marks & Spencer (M&S), but has placed its target price under review after a better-than-expected fourth quarter.The broker admitted that the trading update on Thursday offers a "glimmer of hope". Analyst Bethany Hocking said: "We still have concerns about whether M&S's clothing offer is becoming less relevant to its core shopper; this statement does show some signs of progress, however, and the shares should go higher today."Canaccord Genuity has reiterated its 'buy' rating and 399p target rice for asset management group Ashmore after a trading update showed strong inflows in the third quarter."Ashmore offers investor a good entry point in respect of price-to-book multiple with much of the emerging market premium inherent in the stock, in the past, has dwindled away. [...] With no debt on balance sheet, a strong cash generation and c. $330m of balance sheet cash at H113 we expect dividend to be progressively strong."Construction firm Balfour Beatty was performing well on Thursday morning after Berenberg upgraded its rating for the stock from 'hold' to 'buy'.The broker said that since the group's 2012 results were released on March 7th, the share price has dropped 19%. This compares with downward revisions to consensus earnings estimates of just 6-7% for 2013-2014.The stock now trades at 7.5 times 2014 earnings, a 25% discount to its long-term average and a 36% discount to its European peers.BC