Icap heads the FTSE 100 leaderboard at midday - on the back of IG's upbeat trading statement earlier.
Everyone involved in trading is seeing a boost from IG's surge. Icap is up 4.7% at 429p. IFA Hargreaves Lansdown is up 3.8% to 440p, and inter-dealer broker Tullett Prebon has risen 2.1% to 337.
Of course, Icap's rise might be to do with its comments at the weekend - that it would relocate if a proposed transaction tax were introduced in the EU, but it is hard to see how investors could be precisely sure how such a move would benefit Icap.
Elsewhere, the banks are not joining in the rally. Royal Bank of Scotland is the biggest faller, down almost 4% to 19.95p, while Lloyds Banking Group is down 1% to 28p and Barclays has fallen 0.7% to 149p.
The FTSE 100 broke through the three-figure gain line earlier - and is now 94 points up, a rise of 1.9%.
The market will be keeping an eye on two things this afternoon. Firstly, the ECB will again reveal how much it spent last week buying Eurozone bonds at 2:30. Last Monday it emerged it had spent €22bn, a record for its bond-buying programme.
The Dow Jones, meanwhile, is expected to open 58 points up on the back of the European rally.
