A 2019 ad deal set off a decade-long standoff between theater chains chasing revenue and studios who need people to actually see the trailers.

AMC now warns ticket buyers to expect 25-30 minutes of ads and trailers before the film begins. The company’s own math behind the gap — and why it is shrinking.

Everyone repeats the same line about a 2:30 trailer limit. A data analysis of nearly 7,000 trailers going back to 1930 shows the opposite is true.