Arizona is leading a multi-US state investigation into whether Apple Inc's deliberate slowing of older iPhones violated deceptive trade practice laws, documents reviewed by Reuters on Wednesday showed.
In the ongoing probe since at least October 2018, investigators have asked Apple for data about "unexpected shutdowns" of iPhones and the company's throttling, or slowing down, of the devices through power management software, documents Reuters obtained from Texas through a public records request showed.
Last week, a separate document obtained from Texas by a tech watchdog group showed that Texas' attorney general was involved in the investigation but did not specify the issues being investigated nor which state was leading the effort.
A majority of US states, representing both Democratic and Republican attorneys general, are teaming up on the investigation, a source familiar with the matter said on Wednesday.
The attorneys general offices in Arizona and Texas declined to comment. Apple did not respond to a request for comment.
Apple came under fire in 2017 when Primate Labs, the maker of software for measuring a phone's processor speeds, revealed that some iPhones became slower as they aged.
Apple later acknowledged that it reduced power demands - which can slow the processor - when an aging phone's battery struggles to supply the peak current the processor demands. Apple said without its adjustments, iPhones would have unexpectedly shut down from power spikes.
Outraged iPhone users said that appeared to confirm long-held suspicions that Apple slowed older devices to encourage users to buy new phones. Apple publicly apologized and slashed prices on battery replacements.
Earlier this year, Apple agreed to pay up to $500 million to settle a proposed class-action lawsuit related to the battery issues.