ATLANTA—Inter-carrier tussles over advertising claims have led to a lawsuit, and Cingular Wireless L.L.C. wants an Atlanta court to validate its assertion that its network has the fewest dropped calls among national carriers.

The suit was sparked by Sprint Nextel Corp.’s challenge to Cingular’s claim. According to Sprint Nextel spokesman Matt Sullivan, Sprint Nextel filed a compliant with the National Advertising Division of the Better Business Bureau, alleging Cingular does not have the fewest dropped calls. The NAD handles such challenges confidentially, and generally releases information on the issue only when the matter is resolved. However, the NAD closed its review of Cingular’s claim when Cingular decided to take the matter to cour...
(continues)