National Advertising Review Board Recommends CoStar Group Discontinue Claim “The Most Popular Place to Find a Place”

For Immediate Release
Contact: Abby Hills, Director of Communications, BBB National Programs

703-247-9330 /

New York, NY – August 24, 2022 – A panel of the National Advertising Review Board (NARB), the appellate advertising law body of BBB National Programs, recommended that CoStar Group, Inc. discontinue the claim “The Most Popular Place to Find a Place” and that it modify certain advertising to make clear that it is directed only to the rental market. 

The advertising at issue had been challenged before the National Advertising Division (NAD) by Zillow, Inc., operator of a competing real estate website platform for selling, buying, and renting homes and apartments. CoStar Group had agreed to comply with NAD’s ruling but appealed NAD’s decision on certain issues ( Case No. 7045). 

The NARB panel determined that one reasonable message conveyed by the “Most Popular” tagline is that the advertiser’s site is the preferred site for researching available rental properties, a subjective standard. Because the advertiser did not have consumer research to support that message, the panel recommended that the “Most Popular” tagline be discontinued. The panel noted that nothing in its decision would preclude the advertiser from making a properly supported claim that specifies the specific data point, such as “most unique visitors.”

The NARB panel also concluded that prominent references to the brand name “,” in CoStar Group’s commercials that use the “Most Popular” tagline, reasonably convey that the advertising messages are directed to the rental market. To ensure that the ads do not also convey a message about purchases, however, the panel recommended that advertising that refers to “find a place” or comparable phrases should also include at least one conspicuous reference to renters, renting, or a visual that conveys a rental-market message.

CoStar Group stated that while it respectfully disagrees with the panel’s ultimate conclusions, it will accept all of NARB’s recommendations. 

All BBB National Programs case decision summaries can be found in the case decision library. For the full text of NAD, NARB, and CARU decisions, subscribe to the online archive.

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