Such a ruling (assuming it holds) stands to lower Pandora's performance royalty costs. But it's worth noting Pandora's recording royalties (paid to trade group SoundExchange) easily dwarf its performance royalties. New talks with SoundExchange are set to take place this year.
Pandora bought a Rapid City, SD radio station last year in a backdoor attempt to lower its performance royalties. As it is, the company's success at growing mobile ad rates and (ad-free) subscriptions led its content acquisition costs to drop to 46% of revenue in FQ4 from 56% in the year-ago period.