42 Pa. C.S. § 6160
The following words and phrases when used in this chapter shall have the meanings given to them in this section unless the context clearly indicates otherwise:
"Insurer." A foreign or domestic insurance company, association or exchange holding a certificate of authority under the act of May 17, 1921 (P.L. 682, No. 284), known as The Insurance Company Law of 1921; a health maintenance organization holding a certificate of authority under the act of December 29, 1972 (P.L. 1701, No. 364); known as the Health Maintenance Organization Act, a hospital plan organization holding a certificate of authority under 40 Pa.C.S. Ch. 61 (relating to hospital plan corporations); a professional health services plan corporation holding a certificate of authority under 40 Pa.C.S. Ch. 63 (relating to professional health services plan corporations); a fraternal benefit society holding a certificate of authority under theact of December 14, 1992 (P.L. 835, No. 134) , known as the Fraternal Benefit Societies Code; or a risk-assuming preferred provider organization operating pursuant to section 630 of The Insurance Company Law of 1921.
42 Pa.C.S. § 6160