Royal & SunAlliance (R&SA) is facing a bill for legal costs following a High Court decision by Justice Morison.
The insurer had contested the supplier arrangement in a case involving uninsured loss recovery (ULR).
DAS handled the £610 claim and agreed a hire rate with Helphire, as per its usual arrangement for replacement vehicles.
DAS head of claims & assistance Victoria Scott said: "R&SA challenged the DAS agreement on numerous fronts but succeeded on none. It is a clear vindication of our ULR business model, not only for insured hire but also for credit hire.
"In protracted court arguments, R&SA sought an insight into our confidential commercial arrangements with replacement vehicle providers. The judges, however, ruled against R&SA using well established case law and, it was proven that alternative hire rates available to the motorist would have been higher than those paid by DAS. They would have also been without the benefit of a nil excess unless a collision damage waiver were purchased at an additional cost of around £10 per day. This all points to our model being based on a sound structure which, whilst supporting our customer, does not inflate hire claims to the insurance market.
"In the question of subrogation, Morison LJ made the comment that submissions on behalf of R&SA were 'simply wrong and apparently misunderstood the nature of subrogation in his context'".
The nil excess arrangement was also contested on the basis that it might be construed as betterment, as the policyholder was liable for the first £100 on his own comprehensive motor policy. However, Morison LJ concurred absolutely with the DAS submission that it is impossible to portray the nil excess as betterment.
The Helphire daily rate of £29.07 was described as 'reasonably modest', amounting to a total of £610.46 in this claim.
The court refused permission to appeal.
