Mass. Gen. Laws ch. 200A § 5
Subject to the provision of section one A, all intangible personal property not otherwise presumed to have been abandoned under any other section of this chapter, including but not limited to all certificates of ownership, dividends, stocks, bonds, money, drafts and claims for money and credits, except deposits and the increments thereon referred to in section three that are held or owing in the commonwealth in the ordinary course of the person's business, including all such property held by any fiduciary, shall be presumed abandoned unless claimed by the beneficiary or person entitled thereto within three years after the date prescribed for payment or delivery. Any dividend, distribution, interest, accrual, or payment on principal declared, set aside, accumulated, provided for or owed with respect to property presumed abandoned under the foregoing provisions of this section shall itself be presumed abandoned.
Notwithstanding the provisions of the preceding paragraph, any outstanding credit balances to a vendor or commercial customer from a vendor resulting from a transaction occurring in the normal and ordinary course of business shall be exempt from the provisions of this chapter. This exemption shall not apply to unallocated distributions from securities held by financial intermediaries including, but not limited to, brokers, mutual funds, custodians, trust companies and depositories and owing to unknown beneficiaries but held in the intermediary's nominee names.
Mass. Gen. Laws ch. 200A, § 5