Date: 201511
Local time of day: 1201-1800
Location: TEB.Airport, NJ
Flight conditions: VMC
Weather elements / visibility: 10
Light: Night
Aircraft: Medium Large Transport; Low Wing; 2 Turbojet Eng
Operator: Corporate
Operating under: Part 91
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground TEB
Second aircraft: Any Unknown or Unlisted Aircraft Manufacturer
Reporter organization: Corporate
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Situational Awareness; Communication Breakdown
Second reporter function: Pilot Not Flying; Captain
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Incursion Runway
Detector: Person Flight Crew
When detected: Taxi
Result: Flight Crew Took Evasive Action
Contributing factors: Airport; Procedure
Primary problem: Procedure

Narrative: XA07L: We received our taxi instructions from Ground controller to taxi out [to] Runway 24; Kilo; Lima; Quebec; hold short of Runway 19. After the Captain (Pilot Not Flying; Right Seat) read back the taxi instructions to the Ground controller; I (Pilot Flying; Left Seat) repeated the instructions to the Captain and we began our taxi. We subsequently heard ground control issue a taxi clearance for a Learjet to follow us out with the same taxi instructions.XA10L (approx.): While northbound on Taxiway Lima; between Taxiway Echo and Delta; we received clearance from ground control to cross Runway 19 at Quebec and contact tower on the other side of the runway. The Captain (PNF) read back the clearance to cross Runway 19 instructions and I (PF) repeated the crossing clearance to the Captain. Receiving this clearance so far from the runway crossing point; I looked to see if any aircraft were on approach to Runway 19 (landing runway in use and the runway we just landed on 15 minutes prior). There were no aircraft on close-in approach; so I was comfortable with the clearance. Just after Taxiway Delta; I noticed an aircraft; with beacon on; taxiing off ramp and appeared to be headed toward Taxiway Lima towards the approach end of Runway 19. As we turned right on Taxiway Quebec; the Captain (PNF) turned on our Wing and Recognition lights; per our Flight Operations Manual and stated 'Clear Right'. I looked left and noticed the aircraft that I thought would be crossing Runway 19 at Lima; now had all of its lights illuminated and now appeared to be turning on to the Runway 19. My initial thought was this aircraft was taxing down Runway 19 and would hold short of the active departing Runway 24. I stated to the Captain; that airplane appears to be taking Runway 19 for departure. I slowed my aircraft down and continued to watch the aircraft on Runway 19; who now appeared to be accelerating at a slow speed and was not going to hold short of Runway 24. I abruptly stopped the aircraft at the hold short line of Taxiway Quebec and Runway 19 hold lines; told the Captain I am stopping. The aircraft may have transgressed the hold short lines by no more than a foot or two.The captain immediately informed the Ground controller that we were holding our position at Taxiway Quebec for the departing aircraft. After a short pause the Ground controller thanked us and then reissued the clearance to cross Runway 19 at Quebec and monitor tower on the other side. We asked twice who had the clearance there and the Ground controller told us we had the clearance and it was a misunderstanding between the Ground and Tower controllers.XA22L: No further issues with the remaining taxi and takeoff.


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


Synopsis: A corporate jet flight crew reported that after being cleared to cross an active runway they noticed another aircraft commencing takeoff on the same runway. The flight crew stopped prior to crossing the runway; avoiding a potential critical conflict.