Liberty Media's (Nasdaq: LMCA) petition for the right to take de facto control of Sirius XM Radio (Nasdaq: SIRI) was rebuffed as incomplete, so now it seems as if John Malone's eclectic holding company wants to buy its way into control.

Liberty Media has entered into a forward purchase contract to acquire 302 million shares of Sirius XM at a price of $2.15 a share. If physically settled by the third quarter -- as Liberty Media expects -- the company will be shelling out $650 million to acquire a 5.2% stake in Sirius XM. When you combine that with the 40% preferred share stake that the company received three years ago when it bailed Sirius XM out, Liberty Media will effectively own a 45.2% stake in the company.

The announcement was made yesterday morning, so why did Sirius XM close slightly lower on the news? Well, Liberty Media appears to be getting what it seems to want without having to pay a juicy premium. Liberty Media wants a majority stake in Sirius XM. It may not necessarily want to swallow it whole.

Radio is becoming a big business outside of its terrestrial roots. Sirius XM recently raised its subscriber growth projections. The satellite radio star now expects to tack on 1.5 million additional listeners this year. Pandora (NYSE: P) shares bucked the trend during yesterday's down day, popping nearly 9% higher after it revealed that it now has 51.9 million active users, and that the average user streamed 20.5 hours of the service last month.

It's easy to see why Liberty Media would want a bigger piece of the Sirius XM action, even if its original intention in 2009 simply may have been to take over the company and feast on the tax advantages of its beefy net-operating losses.

Radio is valuable again, and it's why Liberty Media is paying far more for its eventual 5.2% stake than it ever had to expose to grab a 40% chunk.

Running of the bulls
I remain bullish on Sirius XM's future. It should come as no surprise that I'm promoting the CAPScall initiative for accountability by reiterating my bullish call on Sirius XM for Motley Fool CAPS.

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