Liberty Media Corp. announced this morning that it bought back 5.2 percent of its outstanding common stock from Comcast Corp. In addition, Sirius XM Radio Inc. will repurchase $500 million of its shares from Liberty Media.

Also today, Liberty Interactive Corp. said planned to spin off its stake in travel website TripAdvisor and its BuySeasons business into a new publically traded company.

The new company will be called Liberty TripAdvisor Holdings. Liberty currently holds a 22 percent economic and 57 percent voting interest in TripAdvisor Inc.

Liberty also plans to recapitalize its Liberty Interactive Group tracking stock into two tracking stocks — QVC Group and Liberty Digital Commerce Group.

Liberty Interactive Corp., which is controlled by cable mogul John Malone, split off from Liberty Media Corp. in 2011. Liberty Interactive owns the QVC shopping channel, some shopping websites and also invests in other companies.

Liberty Interactive shares rose 43 cents, or 2 percent, to $23.30 in premarket trading.

Separately, After Sirius buys back those shares, Liberty Media will still own more than 52 percent of the company's stock.

Sirius shares added nearly 3 percent, or 11 cents, to $3.94 in premarket trading. Liberty Media shares closed at $143.31 on Wednesday.