This remedy is in addition to any other remedy provided by this act or by law.
Provided, That (i) notice of such service and a copy of such process is sent within ten days after such service, by registered or certified mail, by or on behalf of the Insurance Commissioner to such company, association or exchange at its last known principal place of business, and (ii) the receipt of such company, association or exchange or the receipt issued by the post office with which the letter is registered or certified, showing the name of the sender of the letter and the name and address of the company, association or exchange to whom the letter is addressed, and the affidavit of or on behalf of the commissioner showing a compliance herewith, are filed with the prothonotary or clerk of the court in which such action, suit or proceeding is pending on or before the date such company, association or exchange is required to appear or within such further time as the court may allow.
An "organization" means any of the following:
An "out-of-State single employer" means any person acting directly as an employer and has its principal office located in a state other than this Commonwealth.
An "out-of-State trustee" of a fund means a trustee of a fund established by an insurer for two or more employers or established by two or more persons acting directly as employers and the trustee has its principal office located in a state other than this Commonwealth.
A "union-negotiated out-of-State trust" means a trust established under a collective bargaining agreement and which is located in a state other than this Commonwealth.
It shall be the responsibility of the insurer claiming exemption under this subsection to demonstrate compliance with each of the above conditions.
40 P.S. § 46