Small Transport
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 150; Flight Crew Total 2300; Flight Crew Type 1000
Communication Breakdown; Confusion; Situational Awareness
ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Incursion Taxiway
Air Traffic Control Issued Advisory / Alert
Airport; Chart Or Publication; Human Factors; Procedure
I was repositioning the aircraft; empty; from the General Aviation ramp to the Main Terminal Charlie gates to get fuel and pick up my passengers. I received the Green 'Security' Light from the FBO ramp then pulled forward off the ramp at K1 before it turned red again while I called Ground for taxi clearance. Upon receiving taxi clearance; I was instructed to give the Tower a call at a number they provided. I immediately called Tower after I reached the assigned gate. The Controller informed me that I had taxied into the movement area without clearance. I explained to him that I thought that area was still non-movement area; and that there are no hold-short lines or movement area boundary markings or any other type of markings or signage visible from the ramp denoting that you are entering the movement area. The Controller told me that I was the third or fourth person who had done this recently and he was getting tired of it. I apologized for my mistake; and reiterated that it was not intentional; and that I believed at the time that I was still in the non-movement area when I called him.Immediately after arriving at my destination; I called my Chief Pilot and told him what had happened. The next morning the Chief Pilot [provided our] pilot group with proper procedures that are to be followed regarding getting the green light from the FBO and getting Taxi Clearance when exiting the FBO ramp.
When cleared to exit the General Aviation ramp at STL the pilot of a Small Transport aircraft taxied onto K1 prior to contacting Ground Control. The Ground Controller reprimanded the pilot for entering a movement area without a clearance.  Reporter stated there were no airport markings or signage that depicted movement vice non-movement areas when departing the GA ramp.