Commissioner Mike O’Rielly sent a letter last week to the compliance chiefs at Vivendi SA’s Universal Music Group, Sony Corp.’s Sony Music Entertainment and Access Industries Inc.’s Warner Music Group, which control some 80% of the recorded-music market.

The Federal Communications Commission asked the three major music companies for details on their anti-payola policies, citing unspecified recent reports of practices that would violate laws meant to prevent record companies from paying radio stations to play their music.

The Federal Communications Commission asked the three major music companies for details on their anti-payola policies, citing unspecified recent reports of practices that would violate laws meant to prevent record companies from paying radio stations to play their music.

Commissioner Mike O’Rielly sent a letter last week to the compliance chiefs at Vivendi SA’s Universal Music Group, Sony Corp. ’s Sony Music Entertainment and Access Industries Inc.’s Warner Music Group, which control some 80% of the recorded-music market.

Mr. O’Rielly posted a copy of the letter on Twitter on Tuesday, adding: “We’ll get to the bottom of recent accusations at some point [and] then can figure out next steps—if necessary.”