Maybe this helps -
From Boeing Jet Transport Performance Methods:
approach regulatory requirements
There are two separate regulatory requirements that are included in the climb-limited landing
weight. The first of these two is referred to as the approach climb requirement, the second is
called the landing climb requirement.
The airplane’s landing weight must be low enough to meet the legal requirements specified for
whichever is the more restrictive case of the two.
. For twin-engined airplanes the approach climb requirement is usually more limiting than the landing climb requirement. There is no 'factor' on the climb-limited landing weight, and I can't think of anything that would create a difference between the 'dispatch' and 'in-flight' limits