ITV PLC (LSE:ITV) shares fell on Friday despite the UK broadcasting regulator looking at allowing longer and more frequent advertising breaks.
Ofcom said it was launching a review in light of evolving viewing habits and the rise of streaming services.
Previously it has said the frequency of ads could be seen as disruptive to viewing.
Last year ITV made advertising revenue of almost £2bn.
“The market doesn’t seem to have cottoned on to the potential for ITV to earn a lot more money in advertising revenue," said analysts at AJ Bell.
“Having longer ad breaks could certainly move the dial for its earnings. We’ll find out later in the summer when Ofcom updates on its review.”
The shares were down 1.8% to 64.1p by lunchtime on Friday.