The FTC said $1.5 billion will go into a fund to repay eligible subscribers, with the remaining $1 billion collected as a civil penalty. The settlement requires Amazon to add a "clear and conspicuous" option to decline Prime during checkout and to simplify the cancellation process.

The FTC alleges that some unsuspecting customers may have been pushed into a Prime membership they didn't know how to cancel.

Chun also ruled that two Amazon executives named as individual defendants — Neil Lindsay and Jamil Ghani — were so entwined with the Prime program that they will personally face liability if the jury sides with the FTC. A third, Russell Grandinetti, could also potentially face personal liability if the jury so decides.