Two or more insurers mutually may agree to adhere to rates, rating plans, rating systems or underwriting practices or uniform modifications thereof, all subject to the following conditions:

(1) All of the terms of the agreements shall be in writing executed on behalf of each such insurer.

(2) An executed copy of every such written agreement and of every modification thereof shall be filed with the commissioner.

(3) Within a reasonable length of time after every such filing, the commissioner shall either approve or disapprove such agreement or modification. No such agreement or modification shall be effective unless and until approved by the commissioner.

(4) The commissioner shall not approve any such agreement or modification which:

(a) Constitutes or would tend to result in an unreasonable restraint upon free competition;

(b) contains terms otherwise tending to injure the public interest.

(5) No cause of action shall lie in favor of any insurer which is party to any such agreement against any other insurer party thereto on account of any breach thereof.

(6) All rate filings covered by such agreement shall be subject to the provisions of this chapter or of other applicable law.

(7) The commissioner may after a hearing thereon and for cause withdraw any approval previously given any such agreement or modification.