More than a year after its use of illegal "defeat device" software in diesel cars was first revealed to the public, Volkswagen is still dealing with the effects of the "Dieselgate" scandal.
The automaker continues to work toward a way to modify affected cars to meet emissions standards, as it continues to negotiate with U.S. regulators over two different types of affected diesel engines.
It also faces numerous lawsuits from different parties worldwide.
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Several of those groups are now seeking documents related to VW's use of "defeat device" software—but the company is trying to stem the tide of requests.
Volkswagen is asking a U.S. federal judge reject to requests from groups representing European investors and customers for documents related to the diesel scandal, Reuters reports.
Supplier Bosch, which is also the target of lawsuits related to the VW scandal, has joined the battle on Volkswagen's side to prevent their release.
2010 Volkswagen Golf TDI
Bosch filed a separate request with the court opposing the release of documents, arguing the request for their release was improperly filed.
The lawsuits against Bosch allege the company helped design the Volkswagen "defeat device" software, concealed its use, and demanded in 2008 that the German government provide it with legal protection. Bosch has denied these claims.
Reports of Bosch's involvement in VW "defeat device" software circulated shortly after the diesel scandal broke, and German authorities conducted an investigation into the company.
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Bosch said it has already released nearly 2 million pages of documents related to the scandal, while Volkswagen said it had turned over more than 20 million pages to the U.S. Justice Department, which is conducting a criminal investigation.
The European groups seeking documents represent both consumers and investors, and come from multiple countries.
They include Italian consumer association Altroconsumo; the Wolverhampton City Council, a local government representing a U.K. pension fund; and the Dutch Settlement Foundations, representing owners and investors in The Netherlands.
2010 Volkswagen Golf TDI
VW urged the judge to deny what it called "blatantly over-broad requests."
It noted that German authorities have rejected similar document requests out of concern that release of documents might compromise their own investigations.
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Continuing legal issues are some of the indirect costs Volkswagen will have to deal with as it slowly works to resolve the diesel scandal.
Beyond just modifying or buying back delinquent diesel cars, the company will have to address the damage to its reputation, and the public's dissatisfaction with the opaque manner in which it has handled the scandal thus far.