Film buffs in Cambridge and Bury St Edmunds are fighting to keep their local Picturehouse cinemas.
After Cineworld took over the brand last year, the Competition Commission has said the company is dominating the local market and the cinemas may need to be sold off.
Local film-goers say Picturehouse gave choice and variety often showing the lesser-known and lower budget films that aren't screened in the multiplexes. They're worried the screens could close altogether if a buyer can't be found.
The Competition Commission says half the ticket revenue in the Picturehouse cinemas comes from films which are also shown on Cineworld screens.
Click below to watch a report by ITV News Anglia's Claire McGlasson
Cineworld is facing the sale of cinemas in three areas after being told its takeover of the Picturehouse chain could lead to higher prices for film fans.
Highlighting its concern about the impact on consumers in Aberdeen, Bury St Edmunds and Cambridge, the Competition Commission said it may order the group to sell cinemas to a rival business in these areas.
Cineworld operates 79 cinemas in mainly out-of-town locations, while Picturehouse's 21 outlets tend to be smaller locations in town and city centres.
Cineworld, which acquired the art house chain for #47 million in December, said it was disappointed with the Commission's provisional findings and added that it would continue to lobby the watchdog ahead of its final report in October.
Chief executive Stephen Wiener said Cineworld and Picturehouse were "two fundamentally different businesses" that could operate in the same area.
He added that the company was committed to continuing its expansion and investment in the two chains.
Commission deputy chairman Alasdair Smith said that the two chains faced little competition in the three areas where they are in close proximity.
He added: "We found that when setting the price of tickets, exhibitors take account of the prices of competing cinemas operating in their local area.
"We will now look at ways we can restore competition and protect customers' interests."