(6) The term "debt collector" means any person who uses any instrumentality of interstate commerce or the mails in any business the principal purpose of which is the collection of any debts, or who regularly collects or attempts to collect, directly or indirectly, debts owed or due or asserted to be owed or due another. Notwithstanding the exclusion provided by clause (F) of the last sentence of this paragraph, the term includes any creditor who, in the process of collecting his own debts, uses any name other than his own which would indicate that a third person is collecting or attempting to collect such debts. For the purpose of section 808(6), such term also includes any person who uses any instrumentality of interstate commerce or the mails in any business the principal purpose of which is the enforcement of security interests. The term does not include --
(A) any officer or employee of a creditor while, in the name of the creditor, collecting debts for such creditor;
(B) any person while acting as a debt collector for another person, both of whom are related by common ownership or affiliated by corporate control, if the person acting as a debt collector does so only for persons to whom it is so related or affiliated and if the principal business of such person is not the collection of debts;
(C) any officer or employee of the United States or any State to the extent that collecting or attempting to collect any debt is in the performance of his official duties;
(D) any person while serving or attempting to serve legal process on any other person in connection with the judicial enforcement of any debt;
(E) any nonprofit organization which, at the request of consumers, performs bona fide consumer credit counseling and assists consumers in the liquidation of their debts by receiving payments from such consumers and distributing such amounts to creditors; and
(F) any person collecting or attempting to collect any debt owed or due or asserted to be owed or due another to the extent such activity (i) is incidental to a bona fide fiduciary obligation or a bona fide escrow arrangement; (ii) concerns a debt which was originated by such person; (iii) concerns a debt which was not in default at the time it was obtained by such person; or (iv) concerns a debt obtained by such person as a secured party in a commercial credit transaction involving the creditor.