With Nokia losing its polish, Finnish journalists have been happy to jump onto the Angry Birds story.

And now they're digging into some of the financial issues surround the company; most notable among which is how much the company is worth.

Zynga was rumoured to have offered over $2 billion for it in 2011, while various Rovio insiders have pushed the valuation higher.

Now Finnish website Arvopaperi has made its own attempt.

Without citing any sources, it puts the US valuation of the developer at between $6 to 9 billion.

Rovio is expected to file for IPO in 2013, possibly in the US.

Big bird

This is quite a leap, given that CMO Peter Vesterbacka said the company's 2011 annual sales were around $100 million - and even taking into account his oft repeated mantra that it's 'insanely profitable'.

Assuming Arvopaperi's argument that such a fast growing company could be valued at 20 times sales, this would require Rovio's revenue in 2012 to be at least $300 million.

That's a lot of t-shirts and plushes, given the most direct cash Rovio can currently make from a mobile user is the price of a game (99c-$4.99) and a 99c in-app purchase.

Big daddy

More interesting, perhaps, is the detective work that's been carried on Rovio's ownership.

It's known the main shareholder was Kaj Hed, father of CEO Mikael Hed and uncle to executive Niklas. He invested at least $1 million into the company when it was a start up.

Checking with the Finnish governmental registry, it's revealed that his Trema International Holdings owns 69.7 percent of the company, with investors Accel Partners and Atomico Invest both having a 10 percent share.

They injected $42 million into the company in March 2011.

Other shareholders include Niklas Hed (4.3%) Peter Vesterbacka (3.1%), Mikael Hed (0.6%), Felicis Ventures (1%), while Rovio's employees have a collective 1.3 percent share.

[sources: Arvopaper / Arctic Startup]