B747 captain reported a momentary overspeed probably caused by wake turbulence encounter.

Attributes
ACN	1273021
Time
Date	201506
Local Time Of Day	0601-1200
Place
Locale Reference	EDDF.Airport
State Reference	FO
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Make Model Name	B747 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Descent
Flight Plan	IFR
Person 1
Function	Pilot Not Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 235 Flight Crew Total 12158 Flight Crew Type 9132
Events
Anomaly	Deviation - Speed All Types Inflight Event / Encounter Wake Vortex Encounter

Narrative:

During descent with autopilot and ats (automatic throttle system) on; aircraft experienced momentary over speed due to suspected wake turbulence encounter in otherwise smooth air.

Original NASA ASRS Text

Title: B747 Captain reported a momentary overspeed probably caused by wake turbulence encounter.

Narrative: During descent with autopilot and ATS (Automatic Throttle System) on; aircraft experienced momentary over speed due to suspected wake turbulence encounter in otherwise smooth air.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.