As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DECLARED EMERGENCY, AT FL 410 ENGINE DRIVEN HYDRAULIC -B- SYSTEM LIGHT ILLUMINATED, -B- SYSTEM INDICATES ZERO. INSPECTED HYDRAULIC SYSTEM FOUND -B- SYSTEM ELECTRIC PUMP LEAKING. REMOVED AND REPLACED ELECTRIC PUMP AND CASE DRAIN FILTERS PER MM.