Section 5D. (a) A placement agency, as defined in section 1A of chapter 15D, holding records relating to an adopted person, the biological parents of an adopted person or the adoptive parents of an adopted person shall:
(1) release to such adopted person, if he has reached the age of eighteen years, upon his written request, information about his biological parents which will not identify or tend to lead to the identification of the biological parents or their present or former locations.
(2) release to a biological parent of an adopted person, upon the biological parent's written request, information about such adopted person which will not reveal or tend to reveal his identity after adoption or his present or former locations, and which will not tend to lead to his identity after adoption or present or former locations.
(3) release to an adoptive parent, if the adopted person is under the age of eighteen years, upon the adoptive parent's written request, information about the adopted person and his biological parents which will not identify or tend to lead to the identification of the biological parents or their present or former locations.
Such information shall include such nonidentifying information which the agency holds concerning the medical, ethnic, socio-economic, and educational circumstances of the person. The agency, in its discretion, shall further release such nonidentifying information concerning the circumstances under which the adopted person became available for adoption as it deems to be in the best interest of the person so requesting.
(b) If a placement agency, as defined in section nine of chapter twenty-eight A, has received written permission from a biological parent of an adopted person to release the identity of the biological parent to the adopted person and the said agency has received written permission from the adopted person, or written permission from the adoptive parents if the adoptive person is under the age of twenty-one, to release the identity after adoption of the adopted person to the biological parent, then the agency shall release the identity of the adopted person to the biological parent and the identity of the biological parent to the adopted person; provided, however, that if the biological parent is surviving, that he or she has given written consent at least thirty days before the release of said identifying information. The term ''biological parent'', as used in this subsection, shall mean a biological mother, or a father named on the birth certificate of the adopted person filed in court with the adoption papers, or a man who has signed, as father, an adoption surrender filed in court with the adoption papers.
(c) Information released to a person pursuant to paragraphs (a) and (b) shall be provided in writing if such person so requests.
(d) Such placement agency shall:
(1) release to the biological parent of an adopted person, upon the biological parent's written request, any personal data, as defined in section one of chapter sixty-six A, which it holds relating to the biological parent.
(2) release to an adoptive parent, upon his written request, any personal data, as defined in section one of chapter sixty-six A, which it holds relating to the adoptive parent.
(3) in making any disclosure of information pursuant to this paragraph, the agency shall remove personal identifiers relating to a third person. No agency shall rely on any exception contained in clause Twenty-sixth of section seven of chapter four to withhold personal data otherwise accessible under this paragraph.
(e) All other adoption records held by such placement agency shall be confidential and shall not be released.