Apple is accused of slowing down millions of iPhones to force users into buying new ones.
A class-action lawsuit seeks $2 billion in damages for iPhone users who were affected by the throttling.
The lawsuit alleges that Apple used software updates to intentionally slow down older iPhones.
Apple had previously admitted to slowing down older iPhones, but said it was to preserve battery life.
Critics argue that Apple should have been more transparent about its software updates and the impact on older iPhones.
The lawsuit covers iPhones from the iPhone 6 through the iPhone 7 Plus.
The throttling allegedly occurred after users downloaded the iOS 10.2.1 software update.
Apple agreed to pay $500 million in 2020 to settle a similar lawsuit over iPhone throttling.
The latest lawsuit seeks to represent all iPhone users in the US who were affected by the throttling.
If successful, the lawsuit could lead to significant financial damages for Apple and force changes to its software update policies.