211 CMR, § 75.06
The NICB is hereby authorized to make assessments, in such manner as its Governing Board may determine, among all licensed insurers in the Commonwealth, to reimburse NICB for the costs of the performance of its duties under M.G.L. c. 175, § 113O. Such assessments shall be prorated upon the basis on net fire and theft premiums written under comprehensive policies, or insurance pertaining to the ownership, use or maintenance of motor vehicles written by each insurer in the Commonwealth. Each such insurer which is a member of the NICB shall be entitled to a credit against the assessments authorized hereunder for all assessments directly related to Massachusetts premiums paid by it to the NICB on account of its membership during the period covered by said assessment.
211 CMR, § 75.06