It was another eventful week for the only satellite-radio provider. Shares of Sirius XM Radio (SIRI) were heading toward a down week until spiking sharply higher in the final minutes of trading on Friday. A better-than-expected decision on future rates by the Copyright Royalty Board triggered a late rally in the shares, sending the stock to a welcome 5% pop on the week. The Dow and tech-heavy Nasdaq fell slightly.

What else happened on the Sirius XM front this past week? Well, beyond the royalty-rate news, Sirius XM extended its partnership with Hyundai and closed out November with its highest short interest of the year. Non-Sirius XM news that could have an impact on the company this past week include John Malone's gobbling up of a majority stake in TripAdvisor (TRIP 0.11%) and a tightening of policies at CBS's (PARA -0.47%) last.fm.

Let's take a closer look.

Royalty isn't just for the King of All Media
Late on Friday afternoon, the Copyright Royalty Board decided Sirius XM's music royalty rate will go from 8% of gross revenue this year to 9% next year, advancing after that at 0.5% increments through 2017. The increases are substantial, but many feared that they'd be even worse. Sirius XM passes on the royalty costs to most of its subscribers through a music-royalty fee, and going too high would probably result in defections at a time when alternatives to satellite radio beyond terrestrial radio are growing.

Shorts on the run
It didn't hurt that the royalty news came shortly after Nasdaq reported that there were more than 339 million shares of Sirius XM sold short when the month began. That's the highest number held short in the media giant over the past year -- and that's not all. Keep in mind that shares of Sirius XM have soared nearly 60% higher this year, so the value of those negative wagers is even higher.

Malone gets trippy
As Malone's Liberty Media (STRZA) waits on clearance to take majority control of Sirius XM, one of Liberty's other subsidiaries also had grabby hands. Liberty Interactive (QVCA) -- Malone's Web-centric holding company with ownership of the QVC shopping network and several e-tail websites, including Gifts.com and Pro Flowers -- acquired majority voting power of travel-reviews pioneer TripAdvisor.

Liberty Interactive paid a juicy premium for Barry Diller's TripAdvisor shares, but they also came with supervoting power. Liberty Interactive now owns 22% of TripAdivsor, but it has a fate-dictating 57% chunk of the voting power.

That strategy won't apply to Sirius XM, as there is no class of shares with concentrated voting power. But it doesn't matter, since Liberty Media already has an effective 49.8% stake in Sirius XM, and it's just waiting on regulators to go over 50%.

The last.fm picture show
It isn't easy making money in online streaming. This week found last.fm tightening its belt in an effort to shed money-losing markets and nudge more of its ad-viewing freeloaders into becoming paying subscribers.

In its three largest markets -- the United States, United Kingdom, and Germany -- radio in the desktop client will be available only to paying subscribers after Jan. 15. The traditional Web radio remains a free ad-supported option.

In Canada, Australia, New Zealand, Ireland, and Brazil, there will be no significant changes. Those residents are already paying for the desktop client. However, last.fm will no longer offer its radio service outside the eight countries mentioned.

These changes -- more specifically, the move to start charging its stateside users wanting to go through the desktop client -- will benefit Sirius XM as it rolls out its own platform later this month. It will also be interesting to see whether Sirius XM eventually takes its online offerings global -- at least in terms of its personalized radio offering. It's unlikely to happen right away, given the country-by-country licensing challenges, but it's a welcome reminder that there may one day be a whole world for Sirius XM out there beyond its satellite reach, thanks to the Internet.

Running of the bulls
I recently put out a premium report on Sirius XM Radio, detailing the challenges and opportunities that await investors that are both long and short the dynamic media giant. A year of updates is also included with the report. Click here to check it out now.