Some good news for AT&T customers who have grandfathered unlimited data plans. Going forward, AT&T will throttle customers with unlimited data plans only when they’re in areas that are experiencing network congestion. 

The company has silently updated its support documents to say the following, which was first discovered by Ars Technica:

“As a result of AT&T’s network management process, customers on a 3G or 4G smartphone or on a 4G LTE smartphone with an unlimited data plan who have exceeded 3 gigabytes (3G/4G) or 5 gigabytes (4G LTE) of data in a billing period may experience reduced speeds when using data services at times and in areas that are experiencing network congestion. All such customers can still use unlimited data without incurring overage charges, and their speeds will be restored with the start of the next billing cycle.”

In 2012, AT&T had started throttling top 5% of the unlimited data plan subscribers to 2G speeds. But was forced to make a change in the policy after a backlash for its unlimited data plan customers. It then added a data cap, and started throttling its grandfathered unlimited data plan users after they consumed 5GB of LTE data or 3GB of 3G/4G data in a month. Many AT&T users have reported speeds slower than 512kbps despite being on LTE and paying the carrier for an “unlimited” plan.

This even led the FTC to file a case against the carrier late last year. The case is still pending trial in the court, and AT&T is likely to be fined for throttling the data speeds of its customers without informing them. AT&T has argued that it throttled heavy data users to “manage” its network better, but happily provided proper LTE speeds to customers who were subscribed to its 5GB+ data packs.