SAN FRANCISCO, United States (AFP) — Apple’s move to slow down older iPhones as batteries weaken is under scrutiny by US prosecutors and stock market regulators, according to a report Tuesday by Bloomberg.

The US Department of Justice and the Securities and Exchange Commission are investigating whether Apple broke the law by failing to disclose a software update that made older iPhone models function slower, Bloomberg reported, citing unnamed people familiar with the matter.

It was said to be too early in the probe to speculate regarding the potential for Apple to be accused of wrongdoing.

The SEC told AFP that it would not comment, and neither Apple nor the DOJ replied to AFP inquiries about the report.

Apple admitted late last year that it intentionally slowed down older models of its iPhones over time.

The company said this was to extend the performance of the phone, which uses less power when running at slower speeds, and was to prevent unexpected shutdowns due to a low battery charge.

It has denied incorporating planned obsolescence and plans to release a software update later this year that will let people turn off the iPhone-slowing feature.

In late December the company issued an apology for slowing older models and said it would discount replacement batteries for some handsets.

A French investigation into possible “planned obsolescence” or “fraud” by Apple is being led by antitrust and consumer protection specialists in the French economy ministry.

Planned obsolescence is a widely criticized commercial practice in which manufacturers build in the expiry of their products so that consumers will be forced to replace them.

Critics have accused Apple of nudging iPhone users to upgrade to newer models by letting them think it was the handsets that needed replacing, rather than just the battery.

The California-based group faces lawsuits in the United States and Russia over the matter.

The notion that people will opt to replace batteries instead of buying new iPhones, or that the company’s reputation was bruised, is playing into concerns that Apple may be selling fewer of its iconic handsets than anticipated.

Apple is expected to reveal the latest iPhone sales figures in its quarterly earnings release on Thursday.