From the above report:
"According to the FAA, the pilot's possession of a commercial pilot certificate was only one of several requirements that he needed in order to transport passengers for hire. The pilot had indicated to FAA personnel his intent to obtain the requisite air carrier (air taxi) operating certificate, which would have provided the requisite authorization pursuant to 14 CFR Part 135. However, the authorization had not been granted.
"Personnel at the passengers' Bishop-based business office indicated to the Safety Board investigator that the passengers desired to reimburse the pilot for the cost of their transportation. However, the pilot pointed out that he "did not have enough time in the aircraft type to act formally as a charter pilot." It was therefore agreed that "in exchange for the favor of the flight" the pilot would receive a photograph from the passengers, who were professional photographers.
"The FAA's Western Pacific regional counsel reported to the Safety Board investigator that this type of compensation in lieu of holding the requisite air carrier certificate is not permissible under its existing regulations. The pilot did not appear to have been sharing expenses."