Both designs have a round clock face with black indicators except for the second hand which is red.
An SBB spokesman says the rail company is "proud" the tech giant chose to copy the 68-year-old design.
But Reto Kormann told The Associated Press on Friday that Apple hadn't asked for permission before doing so.
Kormann says SBB will seek an amicable agreement and compensation from Apple.
An Apple representative in Germany declined to comment immediately on SBB's claim.
Apple itself has launched several patent, design and trademark claims against rival companies in the past.
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