SBB, which holds the trademark for a 1944 design by Zurich-born engineer Hans Hilfiker, said last month it might challenge the U.S. company after the clock appeared on a new operating system for the iPad.

"For the use of the clockface on certain Apple devices such as iPads and iPhones, the parties have negotiated an arrangement that enables Apple to use the SBB station clock under a license agreement," SBB said on Friday.

The cost of the licensing fee and further detail of the agreement will remain confidential.

"It is a design icon that has obviously lost none of its appeal in the digital age," the SBB said. "Even now, it symbolizes the innovation and reliability that are key qualities attributed to both SBB and Switzerland as a whole."

Hilfiker designed the minimalist clock to help travelers check the time at a distance while hurrying to catch trains.

In 1953, he added a red second hand in the shape of a railway guard's signaling disc, which pauses briefly at the top of each minute "to enable trains to depart punctually", as he put it.

Mondaine Group, the company that has held the license since 1986 to make clocks and wristwatches for consumers based on the design classic, said it was not involved in the SBB deal.

"As an exclusive licensee, we are surprised to hear about the licensing agreement between SBB and Apple," Ronnie Bernheim, the company's co-owner, told Reuters, but declined to say whether he would take any further action.

The Design Museum in London and the Museum of Modern Art in New York both included Hilfiker's clock among examples of outstanding 20th-century design.

Apple won a sweeping legal victory in August when a U.S. jury found Samsung Electronics had copied critical features of the iPad and iPhone.

(Reporting by Emma Thomasson; Editing by Dan Lalor and Jane Merriman)

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