John Malone’s Liberty Media continues to slowly raise its stake in Sirius XM Radio.

The satellite radio firm, led by CEO Mel Karmazin, reported in a regulatory filing late Tuesday that Liberty has bought additional stock to take its ownership from 48.1 percent to 48.8 percent.

It paid around $2.53 each for about 40 million shares in the roughly $100 million purchase.

The latest acquisition of Sirius shares by Liberty comes just weeks after the company’s most recent increase in its stake. Liberty management has said it plans to take control of Sirius, but has kept its options open for when and how.

Earlier this month, Liberty filed a second application with the FCC asking the agency for approval to take full control of Sirius by buying enough stock to take its stake to more than 50 percent.

Liberty management has signaled it could replace Sirius CEO Karmazin, whose contract expires at the end of the year, pay dividends, buy back stock and spin off its Sirius stake to Liberty investors once it takes control.