KDKA claims (and is able to back up that claim) that they were the
first COMMERCIAL broadcast stations.

Except that KDKA wasn't selling any commercials back in 1920. (there is
some evidence WJZ - now WABC - was the first station to sell airtime to
an outside advertiser, in 1926. Before then, the economic justification
for a broadcasting station was to advertise the licensee's own
products/services.)

Arguably KDKA was the first station to take out a license for the
specific purpose of broadcasting. (Doc Jerrold's KQW (now KCBS) made
its first broadcast at a time when no licenses were required at all.
Wisconsin's 9XM (now WHA) was licensed as an experimental station. Both
stations did eventaully take out broadcasting licenses, but not until
after KDKA and other stations had already done so.)

There is evidence that KDKA's well-publicized first broadcast (of
returns of the 1920 election) was not made under the KDKA license, since
that license was not issued in time. KDKA already had an experimental
license and likely used that license to make the election broadcast.

Really, who was first depends on definitions.

See http://earlyradiohistory.us/sec024.htm for more information.

--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com