Tesla (TSLA) has a contract to use laser-sensor technology from Luminar Technologies (LAZR) for testing and development, Bloomberg reports, citing people familiar with the matter. A photo of a Tesla Model Y with a roof rack of lidar sensors posted to Twitter on Thursday stoked speculation that the companies were working together, Bloomberg points out. Luminar sold Tesla the sensors on that Model Y as part of an agreement between the companies, sources told Bloomberg. It’s not clear what Tesla’s intentions are with Luminar’s lidar, the people added. Tesla engineers could be benchmarking their camera-centric self-driving system against lidar; they also could be testing lidar for future use, Bloomberg notes. Shares of Luminar are up 6%, or $1.27, to $22.68 in early trading.