IMSS appoints substitute in Yucatán to sign resolutions of the state body

Licenciada Brianly Hernández Lugo, head of the Legal Services Department, will fill in for the absences of Doctor Gustavo Ignacio Prieto Torres at the head of the State Decentralized Administrative Operation Body of Yucatán of the Mexican Social Security Institute (IMSS). The designation was recorded in the Official Gazette of the Federation (DOF) on Wednesday, September 23, 2026, page 87, and empowers the official to sign and process the body’s documentation, including the signing of the resolutions that it must issue.

The notice was signed by Prieto Torres himself in Mérida, Yucatán, on August 13, 2026, in exercise of the powers corresponding to him as head of the decentralized body. The document is addressed to federal, state, and municipal authorities based in Yucatán, as well as to employers, insured persons, and the general public; therefore, the substitution takes effect against third parties processing matters before the institute’s state representation.

The IMSS operates in the federal entities through decentralized administrative operation bodies, which are responsible for the provision of services, collection, and the resolution of matters within their jurisdiction. The substitution of its head is a mechanism provided for in the Internal Regulations of the Mexican Social Security Institute to prevent the interruption of these functions during the absences of the person in charge.

Powers assumed by the substitute

• Sign and process the documentation corresponding to the decentralized body.
• Sign the resolutions that must be issued by the State Decentralized Administrative Operation Body of Yucatán.
• Act during the absences of the head, without this implying an appointment other than her own position.

The notice specifies that the designation falls to the person who already serves as head of the Legal Services Department, the normative and legal support area of the body itself. The authorization covers the signing and processing of documentation, as well as the signing of resolutions, which includes the administrative acts that the institute issues regarding social security in the entity.

Legal basis and background of the appointment

The notice is based on Article 251-A of the Social Security Law and Articles 138, 139, 144, and 155, fraction XXXII, subsections a) and b), of the Internal Regulations of the Mexican Social Security Institute, as well as Article 158 of the same regulation for the purposes of the substitution.

Prieto Torres himself was appointed head of the body through Agreement ACDO.DN.HCT.070426/96.P.DG, approved by the institute’s H. Technical Council on April 7, 2026. That agreement is what empowers him to exercise the duties of the position and, consequently, to designate who will substitute for him during his absences.

Who is notified and what are the effects

• Federal, state, and municipal authorities based in Yucatán.
• Employers and insured members of the institute.
• General public.

Publication in the DOF provides certainty to the procedures and processes followed before the state representation of the IMSS, as it identifies the person authorized to sign and resolve matters while the titular head is absent. The notice appears in the September 23, 2026 issue with official reference R.- 580479.

For beneficiaries, employers, and firms litigating labor and social security matters in Yucatán, the notice clearly establishes who can sign and issue resolutions on behalf of the decentralized body during the absences of the titular head, which prevents procedures or notifications from being directed to someone other than the authorized person.

Source: Official Gazette of the Federation, September 23, 2026, notices of the Mexican Social Security Institute, p. 87 (official reference: R.- 580479).