T-Mobile has had a few encounters with the National Advertising Division (NAD) in the past, and today the group is going after T-Mo once again.

The NAD today recommended that T-Mobile stop using its “Best Unlimited Network” advertising. This ad tagline came under NAD review due to a complaint from AT&T.

In its recommendation, the NAD explains that carriers should be free to promote the advantages that it offers to consumers. When a wireless carrier uses comparative advertising claims, though, it must back up those claims to avoid misleading customers and ensure that all providers are on a level playing field.

For its “Best Unlimited Network” ads, T-Mobile pointed to the six OpenSignal network awards that it won in August 2017. T-Mo used data from Ookla in Q3 2017 that said T-Mobile had the fastest LTE download and upload speeds, going on to argue that its superior latency and 4G availability shows that its network is best for unlimited high-speed data users. T-Mo also cited the extras that it offers to unlimited customers, saying that they’re better than the features offered to subscribers of competing carriers.

AT&T argued that the OpenSignal and Ookla tests “were a poor fit for the challenged claim.”

The NAD says that T-Mobile’s evidence doesn’t match the breadth of the “Best Unlimited Network” claim that it makes. It feels that T-Mo hasn’t provided evidence that its network is better at providing talk or text services, or in providing high-speed data more reliably to a larger coverage area. The NAD also says that T-Mobile’s unlimited plan features are elements of T-Mo’s plan and not the network, so they don’t support T-Mobile’s “Best Unlimited Network” claim.

T-Mobile responded by arguing that for consumers weighing what makes a network the “Best Unlimited Network”, having the fastest data speeds is more important than other attributes. However, the NAD does not feel that there’s any evidence to support that argument.

T-Mobile has said that it’s a “long-time support of the self-regulatory process, but is disappointed with the NAD’s decision” and that it plans to appeal to the National Advertising Review Board.

Source: NAD