Security group G4S (GFS) rises 3% to 249.15p on rumours that Charterhouse may buy its cash solutions business for $1.6 billion. Market gossip is also behind a 1.3% rise in Qinetiq (QQ.) to 195.4p. Press reports suggest the defence group will be broken up, led by the sale of its American division. The Sunday Times says sale documents were sent to potential suitors last week, citing a potential £300 million to £400 million price tag. That could be over-ambitious, as we discuss in this article.

Private investors will get a chance to participate in the stockmarket listing of Alton Towers-to-Legoland operator Merlin Entertainments. Read our news analysis for all the details.

Costain (COST) is to participate in a revival of the UK nuclear power industry with a new plant to be built at Hinkley Point in Somerset, sending its shares up 0.7% to 278p. EDF Energy, Areva, China National Nuclear and China General Nuclear Power are involved in a consortium to fund and build the plant. Costain has been appointed as a major contract partner in the construction process, providing design and delivery of the water cooling systems.

Investors discussion boards are once more flung into furious debate as insurance claims outsourcing specialist Quindell Portfolio (QPP:AIM) says it will top market forecasts for 2014. The current year third quarter update shows progress with several substantial contracts won, cash collection ahead of plan and new opportunities emerging. Canaccord analysts up 2014 revenue forecasts by 9.3% to £215 million. Read Shares' recent 'Griller' interview with Quindell founder and chairman Rob Terry in which he spells out plans to take Quindell into the FTSE 100.

There's a change at the top for mining investor Anglo Pacific (APF). Chief executive officer John Theobald and chief investment officer Chris Orchard are being replaced by two members of activist investor Audley Capital. Julian Treger and Mark Potter take over in the respective job titles. Anglo Pacific, which derives most of its income from royalty streams on miners' production including Rio Tinto's (RIO) Kestrel coal mine in Australia, is also raising £2.5 million. Treger is contributing the bulk of this money and the remainder is coming from Potter. We'd speculate that Firestone Diamonds (FDI:AIM) could be a potential beneficiary of cash from Anglo Pacific, given that it has a decent asset that needs a large slug of money (to be obtained via multiple sources) and where Treger is a non-executive director. Anglo's shares rise 2.9% to 201p.

A profit warning from Interbulk (INB:AIM) takes shares in the logistics group down 11.9% to 6.5p. Its dry bulk business has been affected by weakness in the European polymer industry.

Ukraine and Russia focused oil and gas producer JKX Oil & Gas (JKX) falls 5.1% to 69.3p as the results from a fracture stimulation on a well in Ukraine come in at the lower end of its expectations.

Chinese coal bed methane play Green Dragon Gas (GDG:AIM) surges 4.2% to 276p as it announces it will surpass its year-end production target of five billion cubic feet of gas. Some of the uplift in output can be attributed to third parties who drilled on its Shizhuang South (GSS) production block. This licence was reaffirmed by the Chinese authorities in July as wells belonging to Green Dragon.

Aerospace group Senior (SNR) gains 1.6% to 280.2p as it confirms trading is in line with expectations. Net debt is down £10 million from the start of the year to £61 million.

Transport software specialist Tracsis (TRCS:AIM) rises 3% to 208.5p after securing a hard-won renewal of a five-year transport industry framework agreement for remote infrastructure condition monitoring. Believed to with Network Rail, future revenues are not guaranteed yet analysts at WH Ireland estimate around £6 million earned over the past two years. Shares flagged Tracsis in August 2012 at 129p (see page 10 of PDF).

Chinese food preservatives play Sorbic International (SORB:AIM) bakes in a 10.5% gain at 10.5p on a well-received trading update. The £6 million cap, which produces the food preservatives sorbic acid and potassium sorbate from Shandong Province, says full-year results to end-September will beat market expectations, with margins improving significantly in August.

Connected health products minnow Fitbug (FITB:AIM) skips the best part of 4% higher to 1.35p after announcing the launch of 'Fitbug Orb', a new Bluetooth Smart, wireless activity and sleep tracker viewed as the company's 'most significant product development to date'.

Drug discovery company Xenetic BioSciences (XEN: AIM) rises 20% to 6.75p on news of potential takeover talks. General Sales & Leasing may table an all-share deal which could be an easy route to getting the business listed in the US. It seems an odd pairing as General Sales run helicopters for sightseeing tours. That interest will be sold if the takeover goes through, leaving General Sales to solely focus on Xenetic.

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Issue Date: 21 Oct 2013