Several fleets with a significant number of diesel-powered Volkswagen vehicles are taking a closer look at how to move forward following revelations that the cars contain software designed to cheat federal emissions standards.

Managers of the commercial fleets, which preferred to remain anonymous, told Automotive-Fleet.com they are re-evaluating whether to retain Volkswagen vehicles on their selector lists. The fleet managers also said they have initiated talks with the automaker about a possible remedy to the issue.

One long-time Volkswagen large-fleet customer with about 2,000 Volkswagen diesels said the company is "definitely taking the VW issue into account, but no final decision" has been made about the 2016 model-year selector list.

The Roche Group has also been taking a closer look at its fleet, which includes Passat TDI sedans in the Roche Diagnostics and Genentech fleets. Bonnie Brown, Roche Diagnostics' former manager of administrative services had purchased 800 Passat TDIs for fleet use by June of 2014.

"At Genentech, we take our commitment to environmental sustainability very seriously," said Susan Willson, a Genentech spokeswoman. "We are currently evaluating the impact of the Volkswagen situation on our fleet and will provide an update when appropriate."

About 480,000 Volkswagen vehicles and 15,000 Audi vehicles were sold in the U.S. market with the software cheat. Globally, about 5 million Volkswagen, 2.1 million Audi, 1.2 million Skoda, and 700,000 SEAT vehicles have been affected. The software cheat wasn't included in any Porsche cars, according to spokesman Peter Heinz Thul.