The local Florida media has confirmed that Siemens will allow its current Walt Disney World Resort sponsorship contract to expire:

Quote Originally Posted by Orlando Sentinel
After a 12-year run, Siemens and Walt Disney Company will end their sponsorship deal in October, according to spokespeople from both companies.

Siemens has sponsored several Disney attractions, including the “IllumiNations: Reflections of Earth” laser and fireworks night show at Epcot and the iconic Spaceship Earth ride.

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No announcements regarding any future sponsorship of or related impacts to the affected attractions has been made.