This is the info I got from an FAA inspector. Omni Energy Services bought American Helicopters and their 135 certificate and operated the former American aircraft on the old 135. The FAA pulled that 135 after an aircraft was crashed due to running out of fuel and there was a post it note on the instrument panel with the fuel level thought to be onboard. After a ramp check of the American Helicopters aircraft, the aircraft were hauled away on trucks. I'm sure there are other versions of this story.
By the way, American Helicopters was some how related to Felton Baker and Houston Helicopters. If you know Felton then this story is all too true.