The Federal Communications Commission voted today to require broadcast stations to post political ad revenue information online, marking a small step forward in campaign finance transparency.

Broadcasters will be required to post political ad files, which previously had been publicly available only in paper form at each station, to a FCC online database. Two of the three commissioners voted for the requirements, which Bloomberg View has supported.

The vote came despite lobbying from media companies including News Corp., NBCUniversal and Walt Disney, who said posting data online would undermine pricing control and give advertisers an unfair leverage.

Even with the increased transparency these online records will provide, there are limitations.

Broadcasters won’t have to upload existing files, only new ones going forward, and there are no plans to make the database searchable. In addition, the only stations affected in the first two years are those affiliated with the top four national networks (ABC, NBC, CBS and Fox) in the top 50 Designated Market Areas. Smaller stations will have until 2014 to comply.

This means we won’t soon receive information from cable news stations, which are receiving an increasing amount of political ad spending. A February report from the Pew Research Center showed cable as the leading campaign news source, with 36 percent of Americans saying they learned about candidates on cable news networks, compared to 26 percent who said they watched network news and 32 percent who go to local TV news for their campaign updates.

Posting large network political ad revenue online is an important move toward shedding light on shady super-PAC spending. Still, there is still a place for do-it-yourself projects like ProPublica’s Free the Files initiative, which encouraged people to go to their local stations and scan the files to post online.

If we truly want full disclosure of political spending, it’s up to us to continue to demand it.

(Kirsten Salyer is the social media editor for Bloomberg View. Follow her on Twitter.)

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