Recently, a ruling issued by the First Administrative Collegiate Court of the First Circuit was published in the Weekly Judicial Journal of the Federation, under the heading: DETERMINATION OF AN INCIDENT AS A WORK-RELATED ILLNESS OR ACCIDENT. CONSTITUTES A DEFINITIVE RESOLUTION THAT CAN BE CHALLENGED BY EMPLOYERS THROUGH THE ADMINISTRATIVE APPEAL ESTABLISHED IN ARTICLE 294 OF THE MEXICAN SOCIAL SECURITY LAW.

The above-mentioned ruling provides employers the possibility to challenge "ST-7" and "ST-9" reports issued by the IMSS that qualify an employee’s injury or illness as work-related accidents, on the grounds that the referred reports are definitive resolutions that affect companies by increasing their accident rate and annual work risk insurance premium for social security purposes.

As of 5 June 2017 (publication date of the ruling) and depending on each specific case, employers have the option to challenge the ST-7 and ST-9 reports issued by the IMSS's Work Health authorities.