Citation Excel (C560XL)
Flight Crew Air Transport Pilot (ATP)
Inflight Event / Encounter Wake Vortex Encounter
Flight Crew Took Evasive Action
Environment - Non Weather Related
We were en route to MHR and leveled off at intermediate altitude of FL360. A B737 was ahead and to our 11 o'clock position at FL380. ATC advised that after we got adequate separation from B737 we would continue our climb to FL400. After several minutes; ATC cleared us to climb to FL400. As we passed thru FL380 we encountered the wake turbulence from B737. Our aircraft was on autopilot but pitched up and rolled left approximately 20 degrees. The autopilot disengaged at the same time I grabbed yoke and disconnect button. This was a momentary upset and I rolled wings level; lowered pitch to a 400 FT/minute climb and continued to FL400. We advised ATC of the upset. The B737 appeared to be 12-15 miles ahead of us on the TCAS. No one was injured.
CE-560XL Captain reported wake vortex encounter climbing through FL380 while 12-15 miles in trail of a B737.