From further reading, the ruling is based largely on the Chairman's testimony. There is some corroborating testimony from other employees backing requests from executives to upload "popular" music to their service to seed. Logs and actual evidence are not provided, and searching a bit found nothing. I'm not digging through PACER for this, be my guest if you are inclined :)
Transcripts are not available so it's impossible to know if context, however the Chairman is quoted stating they "bet the company on the fact that [it] is easier to ask forgiveness than it is to ask permission” to use plaintiffs’ content. Id. Escape discussed the possibility that its strategy of illegally growing its user base before settling with plaintiffs might permit it to collect information about Grooveshark users’listening habits, which it could then sell to plaintiffs for more than Escape."
This would put liability on the company, but I would suspect that it would require backing evidence which we can't see. Considering that there are personal charges brought against 9 other employees, there is an obvious concern that a plea bargain could contaminate testimony of the Chairman. That said, backing testimony does exist.
The plaintiffs claim that logs and source code were destroyed in discovery, but this is a normal claim by RIA lawyers when facts don't yield what they want. Of course the RIA is mentioned all over the court findings, including the initial lawsuit started by UMG and RIA. The initial law suit was over material that was recorded prior to 1972 and was not subject to copyright protection.
I'm so glad that the Copyright laws are here to ensure that the Hendrix family receives money from Jimmy's works. Oh wait, they fuck over everyone they can and pocket everything.. nevermind.