T-Mobile has worked hard to cultivate its image as the "un-carrier," but that doesn't mean it has no rules for users.
Those on unlimited data plans, for example, can only use those plans for approved purposes, the carrier has revealed.
Customers who use their T-Mobile unlimited data plans for things like peer-to-peer (P2P) sharing or always-on webcams or servers will soon receive notices from the carrier, reports Re/code.
T-Mobile wants to reach out to them and "help them change," Chief Marketing Officer Mike Sievert told the site.
Word of T-Mobile's initiative to stop certain heavy data users in their tracks first leaked as an internal memo that the company says was widely misinterpreted.
T-Mobile isn't throttling its unlimited data users on a large scale, the carrier says, but it will take measures against users who it says are breaking the rules.
That includes any P2P file sharing using T-Mobile data network, as well as excessive data use while tethering to a PC.
Interestingly, Sievert said the carrier is starting by reaching out to just 20 customers, though it's unclear how far the problems extend beyond those.
If the customers don't comply, T-Mobile may throttle or even discontinue their service. But Sievert added that when compared with actions being taken against unlimited users by other carriers, like Verizon and Sprint, T-Mobile's measures are "so apples and oranges it's absurd."