Volkswagen supplier Robert Bosch reportedly has rejected vehicles owners’ claims in the US that 38 of its employees conspired with the automaker for a decade to develop technology that enabled diesel vehicles to evade pollution-control tests.

Bosch would defend itself against the “wild and unfounded” allegations made in a lawsuit in San Francisco, the parts maker said in a federal court filing cited by Bloomberg. Bosch also asked that its employees not be named in legal documents.

That likely stems from the very detailed allegations made in one of the online court documents just-auto has seen which specifically names Robert Bosch Gmbh’s chairman, CEO and chief technology officer as a defendant.

Bloomberg noted that lawyers for Volkswagen car owners in the US had revised an earlier lawsuit against the automaker to name Bosch employees they said participated in the emissions-manipulation scandal that came to light in September.

The “ingeniously designed defeat devices” were armed with software provided by Bosch, vehicle owners said in their filing in San Francisco court. The technology could recognise when the car was being tested in a lab or emissions testing station [California and some other states which have adopted the same stricter-than-federal emissions laws have mandatory annual ‘smog tests’ – ed] to feign clean emissions and compliance with pollution standards.

According to the filing cited by Bloomberg, Bosch marketed ‘clean diesel’ technology in the US and lobbied regulators to approve the vehicles included in VW’s settlement. The filing asserts that Bosch also participated in the scheme to prevent US regulators from uncovering the device’s true functionality.

Bloomberg noted the supplier was not included in VW’s US settlement while Bosch said last week it did not see the need to put more money aside for legal costs, leaving its provisions for such issues at EUR650m (US$737m).