An anonymous reader writes: What the case was about:
Sony and other record labels sued Cox (an ISP) for contributory copyright infringement. They claimed Cox was liable because it kept providing internet service to customers it knew were illegally downloading music (after receiving 163,000+ notices).
The ruling (8-1):
Cox wins. The Supreme Court reversed the $1 billion verdict against Cox.
Key holding in plain English:
An internet provider is not automatically liable just because it knows some customers are pirating and doesn’t cut them off.
Contributory liability requires intent — either actively encouraging piracy or offering a service specifically designed for it.
Cox only sold ordinary high-speed internet (which has tons of legal uses), so it is not liable.
Mere knowledge of infringement by users is not enough.