An independent ad-industry watchdog is recommending that T-Mobile stop making claims that its 4G LTE network is the fastest, or that its network is “newer” than Verizon.

The recommendation comes after the National Advertising Division investigated Verizon’s complaint that T-Mobile was making unsupported advertising claims about the speed and age of its LTE network.

The recommendations came after NAD investigated complaints from Verizon leveled at T-Mobile, finding that some of the company’s claims made in advertisements weren’t supported.

The T-Mobile ads in question described Verizon’s system as “older,” and “slower,” and said “they limit you.” The ads also asked viewers, “Why doesn’t Verizon offer unlimited data like T-Mobile?”

Who’s The Fastest?

According to NAD, Verizon challenged T-Mobile’s claim to have the “fastest” 4G LTE network, alleging that its rival relied on data that was not representative of the vast majority of smartphone users.

During the course of NAD’s investigation, Verizon began offering unlimited data and T-Mobile discontinued the ad. However, the watchdog group notes that T-Mobile did not discontinue claims that its network was new or faster than Verizon’s.

To that end, Verizon had argued that T-Mobile based its claim on unrepresentative data. T-Mobile used crowd-sourced data from Ookla and Open Signal as support for its claim that it has the “Fastest 4G LTE network.”

Verizon took issue with this data, noting that users who download the Ookla and Open Signal apps are only a subset of all smartphone users, and this group is likely to include more sophisticated customers who are interested in monitoring the speed they experience when using their mobile device.

The Ookla-measured speeds for Verizon customers may have slowed at the end of their monthly billing cycle when they reached data limits and experienced deprioritization, the wireless company claims.

Further, Verizion claims that customers who were experiencing deprioritization for the first time during the time period crowd sourced data was collected, may have monitored their speeds more closely than customers of T-Mobile who had past experience with data deprioritization.

Because of this, the speed tests collected may have oversampled Verizon customers, creating a misrepresentation of 4G LTE speeds most Verizon customers actually experience.

Coverage Coverage Coverage

In addition to challenging T-Mobile’s speed claims, Verizon also took issue with its rival’s assertion it has the same coverage as Verizon.

The challenged claims included:

• T-Mobile has near-equivalent area and/or geographic coverage as Verizon
• T-Mobile covers 99% of the area covered by Verizon
• T-Mobile covers 313,312 or “311 Million and Counting” Americans with 4G LTE
• T-Mobile “covers 99% of the Americans that Verizon covers” and 99% of Verizon’s customers

The Findings

When it came to T-Mobile’s speed claims, NAD’s review found that Ookla and Open Signal Speed tests conducted in the month after Verizon introduced unlimited data plans might have had a bias in favor of T-Mobile and did not support the wireless provider’s claim to have the fastest 4G LTE network.

As a result, NAD recommended T-Mobile discontinue claims that it has the fastest 4G LTE network. It also recommended that T-Mobile stop asserting that its LTE network is “newer” than Verizon’s and that Verizon’s LTE network is “older.”

Additionally, NAD concluded that T-Mobile provided a reasonable basis for some of the challenged coverage claims.

While T-Mobile had provided a reasonable basis for its coverage calculation that it covers 99.7% as many Americans as Verizon, NAD noted that it was concerned that a claim comparing the number of people covered could be conveyed as being related to geographical coverage.

To this end, NAD recommended that T-Mobile modify ads to remove imagery that suggests it is talking about geography and make clear that the comparison is related to population coverage.

In its advertiser’s statement, T-Mobile says it will “comply with NAD’s recommendations.”

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