((a)) ** In general** Except as provided in subsection (b) or (c) and in sections 1051, 1081, and 1101 of this title, this subchapter shall apply to any employee benefit plan if it is established or maintained—

((1)) by any employer engaged in commerce or in any industry or activity affecting commerce; or

((2)) by any employee organization or organizations representing employees engaged in commerce or in any industry or activity affecting commerce; or

((3)) by both.

((b)) ** Exceptions for certain plans** The provisions of this subchapter shall not apply to any employee benefit plan if—

((1)) such plan is a governmental plan (as defined in );

((2)) such plan is a church plan (as defined in ) with respect to which no election has been made under ;

((3)) such plan is maintained solely for the purpose of complying with applicable workmen’s compensation laws or unemployment compensation or disability insurance laws;

((4)) such plan is maintained outside of the United States primarily for the benefit of persons substantially all of whom are nonresident aliens; or

((5)) such plan is an excess benefit plan (as defined in ) and is unfunded.

((c)) ** Voluntary employee contributions to accounts and annuities** If a pension plan allows an employee to elect to make voluntary employee contributions to accounts and annuities as provided in , such accounts and annuities (and contributions thereto) shall not be treated as part of such plan (or as a separate pension plan) for purposes of any provision of this subchapter other than section 1103(c), 1104, or 1105 of this title (relating to exclusive benefit, and fiduciary and co-fiduciary responsibilities) and part 5 of subtitle B of this subchapter  (relating to administration and enforcement). Such provisions shall apply to such accounts and annuities in a manner similar to their application to a simplified employee pension under .section 408(q) of title 261section 408(k) of title 26