The old British Gas has lobbed a $13 billion cash bid on Origin Energy but once again the press have fallen for the old trick of undervaluing the size of the cheque that will be written out.

Origin has $3.44 billion in debt, so the Brits are actually paying $16.4 billion which is the biggest cash takeover in Australian history when you consider that Rinker was really a US-based company.

The Chinese government is the only logical rival bidder, especially when you consider it last month spent $2.2 billion buying 1% of BP. That would really test the Rudd Government when you consider whoever gets Origin will jack up domestic gas prices.

Whilst BG’s bid is all about coal-seam methane gas reserves in Queensland, there’s another Queenslander rubbing his hands with glee.

Treasurer Wayne Swan should immediately adjust his budget forecasts because if BG’s Origin bid succeeds, he’ll be banking at least $500 million of additional capital gains tax receipts.

If Origin does fall to the Brits, it will exacerbate Australia’s woeful foreign ownership record that sees almost 250 foreign companies generating more than $200 million a year out of Australia and, with the loss of Origin, only 81 Australian companies generating more than $200 million offshore.

However, spending $16.4 billion still won’t make BG one of the 10 biggest foreign investors in Australia. I reckon the list currently sits as follows:

1. Rio Tinto: London-based mining giant which is only 15% Australian-owned, has just two Australian-based directors and owns more than $100 billion worth of Australian resource assets.

2. Glencore/Xstrata: $50 billion courtesy of the bargain basement MIM takeover, plus a booming and burgeoning coal division and the nickel plays Jubilee Mines and Minara.

3. Mitsubishi: 50% stake in all those vast Queensland coal mines run by BHP-Billiton, plus large gas and iron ore exposures which in total would be worth more than $40 billion.

4. Shell: the Woodside stake is worth about $13 billion and Shell’s direct WA LPG and LNG business is now throwing off profits of more than $2 billion a year. Throw in the 25% market share they have of the Australian downstream petroleum market and you are talking assets worth about $40 billion.

5. Singapore Government: controls almost $40 billion when you include Optus, SP Ausnet, Singapore Power, Singapore Airlines, Basslink, Australand and various other property and sharemarket holdings.

7. Exxon-Mobil: 50% of Bass Strait plus various other WA gas and oil interests worth about $35 billion.

8. Chinese Government: the $15.5 billion splurge on 9% of Rio Tinto is the biggest investment but 40% of the Channar iron-ore mine, the $1.38 billion bid for Midwest Corp and various other investments such as 25% of the Portland Aluminium Smelter and 20% of Macarthur Coal would bring the total up close to $30 billion.

9. Mitsui: vast iron ore, coal and gas interests worth about $25 billion.

10. BP: one of the four major downstream players and the one-sixth stake in the North West Shelf is throwing off profits of more than $1 billion a year suggesting the overall Australian business is worth about $20 billion.

Check out this Mayne Report video on yesterday’s Iress Technology AGM that wasn’t.