Allied Progress, which opposes the Sinclair-Tribune merger has bought time on four Sinclair stations for a 30-second spot taking aim at the broadcasters over its corporate fake news warning read by its local news anchors across the country.

Sinclair is not obligated to take the ads, but Allied said it had made a six-figure buy on four Sinclair TV stations--WJLA Washington, KDSM Des Moines, KOMO Seattle and WBFF kin Sinclair's home base of Baltimore.

The one-week ad buy, which launches Friday (April 6) uses the Deadspin online video of the anchors all reading the warning at once, suggesting that is the kind of centralization, and politicization, they have warned about if Sinclair is allowed to merge with Tribune and boost its station ownership to a an audience reach of an effective--with the UHF discount--72% of the nation.

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“We’re running these ads to ensure Sinclair’s local viewers know the company’s politically motivated owners are forcing the anchors they trust to advance a partisan agenda that has nothing to do with news and everything to do with politics," said Karl Frisch, executive director of Allied Progress.

Sinclair has defended the on-air fake news warning as just trying to promote its local news, differentiating it from the unmoderated social media echo-chamber that other news outlets report as news.

While both Justice and the FCC are vetting the Tribune deal, the ad targets the latter, telling viewers to contact the FCC and ask it to stop the merger.

Currently, the FCC's vetting of the deal is on hold awaiting yet another refiling of an adjusted deal as Sinclair works with Justice to try and square it with DOJ's concerns about concentration in ad markets, for one thing. The FCC's review extends beyond antitrust to positive public interest benefits, which Sinclair has said include expanded local news and scale that will allow it to compete with video distribution platforms like cable and over-the-top video.