Mass. Gen. Laws ch. 165, § 13

Immediately after the payment of the capital of an aqueduct company, as authorized by the state secretary, a certificate, signed and sworn to by its president, treasurer and a majority of its directors, stating the fact of such payment, the manner in which the capital has been paid in and has been invested or voted to be invested, and approved by said secretary, shall be filed in the office of the state secretary.