Mass. Gen. Laws ch. 156 § 46E
A stockholder in any corporation which shall have duly voted to consolidate with another corporation in accordance with section forty-six B or forty-six D, who, at the meeting of stockholders, has voted against such consolidation, if entitled to vote, or, if not entitled to vote, has registered his disapproval in writing with the corporation at or before said meeting, may, within thirty days after the date on which the articles of consolidation were filed, make a written demand upon the consolidated corporation for payment for his stock. If such corporation and the stockholder cannot agree upon the value of the stock at the date of the consolidation, such value shall be ascertained and the stock paid for by and transferred to the consolidated corporation in the manner provided in section forty-six.
Mass. Gen. Laws ch. 156, § 46E