The knot appears to to be formally tied. Mining giant Xstrata has confirmed its plans to merge with commodity player Glencore (pic: Glencore boss Ivan Glasenberg) in a £56bn mega deal.

The union was announced on the day Xstrata declared a 20% surge in 2011 profits to £3.8bn. But the deal could still be given a rough ride by some important players - the company owners.

Cosy

One owner is Standard Life, which owns almost 2% of Xstrata. "Although we see some merit in the merger of Xstrata and Glencore the proposed exchange ratio clearly undervalues Xstrata's assets and future earnings contribution," David Cumming, head of equities at Standard Life, is quoted in the Guardian.

Schroders, another asset management company, was similarly downbeat on the deal, claiming Xstrata's growth prospects were superior to that of Glencore's. Certainly there's some shareholder apprehension toward the deal.

The two top execs of both companies, Ivan Glasenberg at Glencore and Xstrata's Mick Davis, the highest paid FTSE 100 boss, both attended the same school. Both are highly driven individuals arguably not used to the partial job-share responsibilities a larger merger would drag with it.

Who pays?

There's also a lot of anxiety about the impact of the merger for consumers: less competition, higher prices all-round (for consumers and manufacturers), and the drying up of external competition generally. Which could see the European Commission take a close interest in the deal.

And although the new company would be listed in London, don't think the new combo will be returning much in the way of cash to the UK tax base. The new company will likely stick to a Swiss HQ and be incorporated in the Channel Islands to keep its liabilities down.