(a) Every insurer shall file with the commissioner every manual of classifications, rules and rates, every rating plan and every modification of any of the foregoing which it proposes to use in this Commonwealth. The filing of the aforementioned shall be made whether or not the coverage is provided on an individual or group basis and whether or not the group policy is issued in this Commonwealth or another state. Every such filing shall state the proposed effective date thereof and shall indicate the character and extent of the coverage contemplated. When a filing is not accompanied by the information upon which the insurer supports such filing, and the commissioner does not have sufficient information to determine whether such filing meets the requirements of the act, he may require such insurer to furnish the information upon which it supports such filing. Any filing may be supported by (1) the experience or judgment of the insurer or rating organization making the filing, (2) the experience of other insurers or rating organizations, or (3) any other factors which the insurer or rating organization deems relevant. A filing and any supporting information shall be open to public inspection after the filing becomes effective.

(b) An insurer may satisfy its obligations to make such filings by becoming a member of, or a subscriber to, a licensed rating organization which makes such filings and by authorizing the Commissioner to accept such filings on its behalf; Provided, That nothing contained in this Act shall be construed as requiring any insurer to become a member of or a subscriber to any rating organization.

(c) The Commissioner shall review such of the filings as it may be necessary to review in order to carry out the purposes of this Act.

(d) Subject to the exception specified in subsection (e) of this section, each filing shall be on file for a waiting period of thirty (30) days before it becomes effective, which period may be extended by the Commissioner for an additional period not to exceed thirty (30) days upon written notice within such waiting period to the insurer or rating organization which made the filing. Upon written application by such insurer or rating organization, the Commission may authorize a filing of a part thereof which he has reviewed to become effective before the expiration of the waiting period or any extension thereof. A filing shall be deemed to meet the requirements of this Act and to become effective unless disapproved, as hereinafter provided, by the Commissioner within the waiting period or any extension thereof.

(e) Any filing with respect to a surety or guaranty bond required by law or by court or executive order or by order, rule or regulation of a public body, not covered by a previous filing, or any filing with respect to a contract or a policy covering any risk or kind of insurance or subdivision thereof for which classification rates do not generally exist in the industry, or which by reason of¹ rarity or peculiar characteristics does not lend itself to normal² classification or rating procedure, shall become effective when filed and shall be deemed to meet the requirements of this Act.

(f) Under such rules and regulations as he shall adopt the Commissioner may, by written order, suspend or modify the requirement of filing as to any kind of insurance, subdivision or combination thereof, or as to classes of risks, the rates for which cannot practicably be filed before they are used. Such orders, rules and regulations shall be made known to insurers and rating organizations affected thereby. The Commissioner may make such examination as he may deem advisable to ascertain whether any rates affected by such order meet the standards set forth in subsection (d) of section three.³

(g) Upon the written consent of the insured stating his reasons therefor, filed with and approved by the Commissioner, a rate in excess of that provided by a filing otherwise applicable may be used on any specific risk. The rate shall become effective when such consent is filed and shall be deemed to meet the requirements of this Act until such time as the Commissioner reviews the filing and so long thereafter as the filing remains in effect.

(h) Beginning ninety (90) days after the effective date of this Act no insurer shall make or issue a contract or policy except in accordance with filings or rates which are in effect for said insurer as provided in this Act or in accordance with subsections (f) or (g) of this section.