The use of so-called "'customer cars' reflects the situation with F1’s engines, which are built by Cosworth, Ferrari, Mercedes and Renault and sold to nine teams."
However, it "would require the agreement of all of the teams and the sport’s governing body," the FIA. Williams Founder & Owner Frank Williams "is said to be against it."
Ecclestone said, "I believe that customer cars will be a good thing. Everybody needs to agree to that, but Frank Williams is the one who is against it."
The current requirement for teams to be a "constructor" comprises the bulk of their research and development costs. The proposed change from Ecclestone "would give the chassis sellers additional income while the weaker outfits would save development costs and gain a more competitive car." Express