Communications services companies rose slightly in volatile trading.

Shares of Zoom Video Communications fell sharply, continuing a highly volatile path for the maker of newly popular video-conferencing software. Zoom shares had more than doubled from June levels at Wednesday's peak over $500, but they fell more than 6% on Thursday.

E.W. Scripps agreed to buy ION Media for $2.65 billion in a move to significantly expand the TV station owner's reach with the backing of Warren Buffett's investment firm Berkshire Hathaway.

Berkshire plans to make a $600 million preferred-equity investment in Scripps to help finance the purchase of closely held ION.

Already a big player in the music and podcasting businesses, Spotify Technology struck a partnership deal with television-and-movie production studio Chernin Entertainment to create television, movies and digital-video programming based on Spotify's hundreds of original series.

Write to Rob Curran at rob.curran@dowjones.com