In the following sentence, I’m curious whether "to combat labor exploitation" only relates to "require documentation" as single or "limit hours, impose age limitations, or require documentation" as whole.
Furthermore, I’m also curious what "require documentation to combat labor exploitation" means.
Just as trucking regulations cap truckers’ driving hours in the
interest of public safety, labor regulations that limit hours, impose
age limitations, or require documentation to combat labor exploitation
may help correct market participants’ biases undervaluing the harm to
third parties or vulnerable participants with particularly weak
There’s some ambiguity because "to combat labor exploitation" comes at the end of the list, but I think it’s reasonable to assume that the authors meant to link all three of the requirements to the phrase. It’s clear that limiting hours, imposing age limitations, and requiring documentation are all ways to limit labor exploitation.
"Require documentation" likely refers to requiring employees to show proof that they’re authorized to work (such as a passport or permanent residence card). A discussion of such documents for the U.S. can be found here. Workers that can’t produce such proof are called "undocumented workers" and are of course susceptible to exploitation because they’re unlikely to complain about poor treatment when they’re working illegally.