(a) Notwithstanding any other provision of this code, an insurer may not consider for the purpose of setting premiums or reducing a claims-free discount for a particular insured physician’s professional liability insurance a lawsuit filed against the physician if:
(1) before trial, the lawsuit was dismissed by the claimant or nonsuited; and
(2) no payment was made to the claimant under a settlement agreement.
(b) An insurer that, in setting premiums or reducing a claims-free discount for a physician’s professional liability insurance, considers a lawsuit filed against the physician shall refund to the physician any increase in premiums paid by the physician that is attributable to that lawsuit or reinstate the claims-free discount if the lawsuit is dismissed by the claimant or nonsuited without payment to the claimant under a settlement agreement. The insurer shall issue the refund or reinstate the discount on or before the 30th day after the date the insurer receives written evidence that the lawsuit was dismissed or nonsuited without payment to the claimant under a settlement agreement.

(c) This section does not prohibit an insurer from considering and using aggregate historical loss and expense experience applicable generally to a classification of physicians’ professional liability insurance to set rates for that classification to the extent authorized by Chapter 2251 and Article 5.13-2. Notwithstanding Section 2251.052(c), an insurer may not assign a physician to a particular classification based on a factor described by Subsection (a).