The National Ad Division is a program of the Council of Better Business Bureaus that investigates claims of misleading or otherwise problematic ads. Complaints typically come from an advertiser’s competition, and recently T-Mobile spoke up about Sprint’s marketing that promises to cut customers’ bills in half, or give them 50% off. The watchdog agreed that the claim made in ads is not, strictly speaking, true.

We’ve been following this problematic campaign since it began in 2014, including when a Sprint executive mentioned that the actual amount customers save works out to more like 20% off their bill.

“NAD determined that references to the limitations are blurred by the fast-moving audio and visual elements of the commercials,” the investigators noted, “which also make the supers, which refer to rate plans as well as limitations and restrictions, difficult to read, notice and understand.”

Even when you visit Sprint’s website to check out the promotion, it still takes some peering at fine print to figure out the restrictions and data overages that apply to customers switching from other carriers. Since nothing in life is simple, data allowances and overage fees depend on the carrier you’re switching from.

The watchdog’s ruling was ultimately that the campaign is correct in that its rate plans are about 50% of comparable plans from T-Mobile, but that the included features aren’t identical, and the required activation fee and device purchase price make it so that customers’ actual bills aren’t cut in half.

Sprint ended its “cut your bill in half” branding during NAD’s investigation, and said that it would comply with recommendations to change their ads to make the differences between their plans and competitors’ plans clearer.

“Sprint’s 50% off promo = 100% bull$#@!” declared T-Mobile CEO John Legere on Twitter.

In a statement to Consumerist, Sprint notes that they are, in the end, pleased that their ads were found to be accurate, if in need of a little clarification.

“Sprint was pleased with NAD’s conclusion that print and Internet advertising claiming 50 percent savings over most T-Mobile Simple Choice rate plans is truthful and accurate… Truthful comparative price advertising benefits consumers, and Sprint is pleased to be able to offer significant value through its Save 50 promotion.”

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