Angry Birds maker Rovio is in the process of a fundraising round that would value the company at $1.2 billion, according to a report by Bloomberg.

That would make the casual games company worth more than Plants vs. Zombies creator PopCap, which games publisher Electronic Arts bought for $750 million. Rovio is still well short of social games maker Zynga, which is valued somewhere between $10 billion and $20 billion and is looking to raise up to $1 billion in its upcoming initial public offering.

Wibe Wagemans, Rovio’s head of global brand advertising, hinted that the company was raising money at VentureBeat’s GamesBeat 2011 conference in San Francisco last month.

“We’re in fast growth mode, so we’re always on the lookout for good money,” Wagemans said. “We’re always interested.”

Angry Birds is a popular game on mobile devices in which players fling birds at structures to try to destroy pigs. It started on smartphones like the iPhone and on tablets like the iPad. It has since expanded to a large number of other platforms like web browsers and TV boxes that are powered by operating systems like Android.

The company finished raising its last round of money — $42 million —  in March this year. Rovio has been expanding through 2010 and 2011 and currently has 50 employees in Finland.

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