Interdealer broker ICAP (IAP) topped the losers board this morning, down 6.9% at 300p, after reporting 'extremely challenging' trading conditions in the nine months to 31 December 2012. The FTSE 100 counter is a good proxy for the global banking sector its serves and that activity has tailed off in March perhaps underlines how trading activity could be damaged by global regulatory moves to curtail the speculative activities of large financial organisations.

Volatility is good for ICAP, which facilitates trading between banks who don't want to deal on exchange, and so this year's monetary loosening by the Bank of Japan, and consequent devaluation in the yen created generated good fees in January and February. Foreign exchange is by far the biggest market and the prospect of an all-out global currency war as economic growth continues to disappoint creates a favourable backcloth, but not if proprietary trading is taxed out of existence or made unfeasible by new rules to ringfence banks' retail and investment banking operations.

For a UK equity fund manger, the FTSE 100 pushing on five-year highs is manna from heaven. Hence no surprise Liontrust Asset Management's (LIO) year-end trading update was always going to be bullish, stock up 1.2% to 166p on news of £233 million of net inflows for the first quarter of 2013.

After an initial rise, the market had second thoughts about Costain's (COST) proposed takeover of May Gurney (MAYG:AIM), sending the predator down 5.9% to 285p. The deal is structured as a merger, but Costain is actually paying a premium to gobble up May Gurney, as we discuss in detail here.

An upbeat trading statement took TUI Travel (TT.) 3% higher to 319.7p. Margins and average selling prices are improving, which leads the travel group to say that its full-year performance should come in at the upper end of its growth targets.

Life insurer Prudential (PRU) fell 3.6% to £10.58 after being fined £30 million by the Financial Services Authority (FSA) over failing to inform the body of its proposed £23 billion bid to buy Asian insurer AIG in 2010. The FSA said management did not tell the regulator of its plans until news of the deal appeared in the media. Chief executive Tidjane Thiam was also censured for his role in the decision not to contact the FSA about the proposed acquisition.

Online insurance company Esure Group (ESUR) fell 1.34% to 295p on the first day of public dealings.

Construction-to-infrastructure equipment specialist Speedy Hire (SDY) jumped 5.1% to 46.75p after winning a £6 million-a-year contract with National Grid (NG.).

Real Estate Investment Trust NewRiver Retail (NRR: AIM) advanced 1.5% to 202p after confirming two pre-lettings in the Forum Shopping Centre in Newcastle-upon-Tyne, which it is re-developing. North Tyneside Council has signed a 30-year break-free lease at an initial rent of £363,000 a year, which it will use as a library and community centre. It has also signed a 10-year lease with a value retailer for £125,000 a year. Management confirmed that they are in advanced legal negotiations to let the final two units.

Luxury car dealership H.R. Owen (HRO) revved up 2.9% to 70.5p on strong annual numbers revealing bumper sales and profits increases. The £16.1 million cap's numbers for calendar 2012 showed revenues surging 26% higher to £243.5 million, driving taxable profits up 44% to £2.3 million, as the business benefited from a recovering new car market and strong performances from brands including Ferrari, Bentley and Lamborghini.

A profit warning from CSF (CSFG:AIM) left the data centre group on its knees, the shares falling 47.2% to 14.25p. The board has now commissioned a strategic review of the company.

Shares in Topps Tiles (TPT) cheapened 2.4% to 61.75p on analyst downgrades accompanying news of disappointing second quarter (Q2) sales amid weaker demand. In a first half pre-close statement, the UK's biggest tile specialist announced a 2.2% fall in Q2 like-for-like sales, versus growth of 1.6% in the first quarter. Highly operationally-geared and exposed to the moribund housing market, the £121 million cap now expects total sales for the half year to March to be in the region of £87.4 million and taxable profits to fall 23% to around £4.3 million.

Interim results from oil services technology play Plexus (POS:AIM) got the thumbs up from the market with the shares gaining 4.7% to 225p. Pre-tax profits rose 13% to £1.7 million and the company, which owns the proprietary POS-GRIP friction-grip method of wellhead engineering, revealed a 'strong forward order book' for POS-GRIP rental wellhead equipment.

Shares in US-based unconventional oil play TomCo Energy (TOM:AIM) fell 6.6% to 1.34p after it revealed it is still waiting on technology provider Red Leaf Resources as it seeks to provide the data needed for a resource upgrade at its Holliday block in Utah.

Iron ore miner Bellzone (BZM:AIM) crashed 40% to 6.9p after a major downgrade to its production forecasts. The shares are now less than half the price paid by Chinese partner Sonangol three months ago, having now built up a 25% stake in Bellzone.

Further delays to a planning application pulled Sirius Minerals (SXX:AIM) down in early dealings, although the shares subsequently rose 7.7% to 21p. The company now expects a planning decision on its potash mine to come in July rather than the previous May target.

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Issue Date: 27 Mar 2013