Lawyers for car buyers say cases should proceed on the basis of the Court of Appeal ruling, but Mr Rathi was more circumspect.
He said that the courts had given different interpretations of the law regarding fixed commissions, while the FCA had already been looking into discretionary commission arrangements.
Lenders involved in the case have asked the Supreme Court to consider the case. In the meantime, dealers and lenders have been given a longer period to deal with complaints.
A clearer idea on whether a “structured redress system” which would either require customers to complain, or ensure firms to go back through cases and automatically pay compensation, would come next year, MPs heard.
Significantly, Mr Rathi said that the regulator was also considering whether the Court of Appeal ruling could have implications for other sectors.
He would not be drawn on which sectors, but analysts have suggested other “big ticket” purchases made on finance could come under the microscope.
In a wide-ranging hearing, the committee of MPs also questioned the FCA on investment risks facing consumers, financial influencers, and the operational effectiveness of the regulator.
