105 CMR 590.000:
STATE SANITARY CODE CHAPTER X – MINIMUM SANITATION STANDARDS FOR FOOD ESTABLISHMENTS
(1) ~Base of Operations. Each caterer shall have as its base of operations a food establishment that shall comply with the provisions of 105 CMR 590.000, except that a facility holding a permit as a residential kitchen shall not serve as the base of operations for a caterer.
(2) ~Notification. Each caterer shall:
(a) ~Notify the board of health of the city or town in which it plans to serve a meal prior to serving any meal elsewhere than in its own food service establishment and shall give written notice to the board of health on a form provided by the board or the Department either prior to or within 72 hours after serving a meal elsewhere than its own food service establishment; and
(b) ~If required by the board of health or its agent, provide the board with a copy of its food establishment permit prior to serving a meal in a city or town other than the one in which its food establishment is located.