Google parent Alphabet Inc.’s heated rivalry with Uber Technologies Inc. over self-driving cars has spilled into the courthouse, after the internet giant sued the ride-hailing company for allegedly stealing trade secrets to jump-start its own autonomous vehicle program.

Anthony Levandowski, a former key manager in the Google self-driving car project, is accused of secretly downloading 14,000 files in December 2015 before departing Alphabet last year to create Otto, a self-driving truck maker acquired last year by Uber.

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