Date: 201511
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 25
Light: Daylight
Aircraft: Medium Transport
Operator: Corporate
Operating under: Part 91
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Reporter organization: Corporate
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Time Pressure; Training / Qualification
Second reporter function: Pilot Flying; Captain
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: General None Reported / Taken
Contributing factors: Company Policy
Primary problem: Company Policy

Narrative: Upon in-range call to company HQ; I was notified of a problem involving our lone passenger's travel documents with respect to US Customs entry requirements. I then called US CBP directly and was notified our passenger was traveling under the visa waiver program; our company is not a signatory carrier and that our passenger could be denied entry into the US. The PIC and I elected to land as planned as our fuel load did not allow a return to departure point.The passenger was detained; the flight crew was asked to remain on US CBP premises; and the airplane was not released. CBP explained to the crew that in order to carry a traveler under the visa waiver program that person must travel on a signatory carrier. Since our company is not an approved carrier the company could be fined. Eventually; the passenger was allowed entry; conducted his business with my company and we were allowed to fly him back the same day.The PIC and I received short notice of this trip and we asked for passenger's documents as soon as possible. Unfortunately; we were not given any information until the night before a planned takeoff [in the early morning] the next day. The only information we were given was an email explaining passenger was a French citizen who works in Beijing and a copy of his passport was attached. I entered relevant information into eAPIS system and our manifests were accepted.Still; I had questions; are we allowed to carry a French citizen? The PIC and I conferred; he didn't know either. I called CBP directly to give them crew and passenger information and arrival ETA. I specifically told CBP officer our passenger was French. Relayed my exchange with CBP to PIC and we both agreed that with no comments from CBP regarding our passenger's status that we are good to go. In hindsight; I should have made some additional calls to confirm travel requirements of our passenger. I could have called our international trip support provider for advice or the company representative responsible for the trip for additional information. I could have asked for a delayed departure for more information. However; at this point I honestly did not know I needed more information. I didn't learn that our passenger was traveling under a visa waiver until I went in the cabin to explain the issue with US CBP to him and he showed me the actual visa waiver document. Additionally; my first time hearing of the signatory carrier requirement was upon initial contact with US CBP.Lesson learned; don't take the trip unless I am completely satisfied all entry requirements are met.


Second narrative: [Report narrative contained no additional information.]


Synopsis: Corporate flight crew flew a foreign citizen traveling under the visa waiver program into the US. Since their company was not a signatory carrier; the passenger could have been denied entry and the company fined.