The market liked the idea of Henderson buying Gartmore in a share for share exchange announced this morning, lifting the buyer's stock 10% from last night's close, and for good reason: assuming it can make the deal work, it will make Henderson's retail business a force to be reckoned with.

The terms of the acquisition would give Gartmore shareholders two new Henderson shares for each three Gartmore shares, giving them 22.5% of Henderson after the deal. Using last night's share prices, the deal valued Gartmore at 92.1p a share, or £335m. Gartmore said it estimated its assets under management at the end of the year at £16.5bn.