There has long been speculation on this... When the port authority was in San Pedro a few months ago - I asked them to clarify and re-clarify. They insisted that I DID NOT need a captain's license. Any type of commercial operation whatsoever must have licensed captains. I assume this means transportation, diving, or any type of water-based tour.
If the rule has changed - I'd like to see something a bit more official from the port authority before I get concerned. Does the PT have a website? Do they print these changes on a letterhead?