The US International Trade Commission (ITC) said Wednesday it had launched an investigation into whether German auto maker Volkswagen and some of its subsidiaries had infringed on hybrid electric vehicle patents owned by Baltimore-based Paice LLC.

The commission hastened to add, though, that it had not yet made any decisions on the merits of the case.

Paice LLC said it was seeking a cease-and desist order, which would block imports and sales of Volkswagen, Porsche and Audi brand hybrid cars in the US.

Tight-lipped management

Wolfsburg-based Volkswagen said they were not willing to comment on the matter while the probe was underway.

The German carmaker has already been in deep trouble after admitting last year it had installed emissions-cheating software in a large number of its cars at home and abroad.

In a letter seen by Reuters on Wednesday, VW Chief Financial Officer Frank Witter told complaining British hedge fund TCI it had made significant progress in implementing a new structure for the group.

But he also acknowledged that an inquiry by law firm Jones Day into who was responsible for rigging exhaust emissions tests was dragging on. "We're all frustrated at the time this is taking."

Witter added Jones Day had to be allowed to continue its work to ensure "no stone was left unturned in the pursuit of truth."

hg/jd (dpa, Reuters)