Faulty Takata airbags have killed 22 people and are responsible for the largest recall in automotive history, affecting 37 million vehicles in the U.S. Some of those cars may be operated by Uber and Lyft drivers, but neither company knows the number or whether their drivers have responded to the recalls, The Information has learned.

Representatives from Uber and Lyft acknowledged that they do not track how many cars in their fleets are subject to auto recalls because they said they expect their drivers to get problems fixed. As drivers could be hurt in an accident, they “have a strong personal incentive to make sure their car is in a safe operating condition,” said Adrian Durbin, a spokesman for Lyft.