"Expenditure", any payment made or liability incurred by a vendor on behalf of a political committee or on behalf of an individual or group required to file a report of ballot question expenditures under section 22.
"Person", a natural person, corporation, association, partnership or other legal entity.
"Subvendor", a person providing goods or services to a vendor or who contracts with a vendor to provide goods or services to a committee or to an individual or group required to file a report of ballot question expenditures pursuant to section 22.
"Vendor", any person including, but not limited to, a consultant who provides goods or services to a political committee or to an individual or group required to file a report of ballot question expenditures pursuant to section 22 and either receives or is promised $5,000 or more in the aggregate during a calendar year by the committee, individual or group for such goods or services or contracts with another on behalf of the committee, individual or group for such goods or services valued at $5,000 or more in the aggregate to be provided to the committee, individual or group.
Mass. Gen. Laws ch. 55, § 18D