# IMSS digital authentication and employer fraud

> Live situation record from CLSTR: https://clstr.news/situations/imss-digital-authentication-and-employer-fraud
> Updated: 2026-09-21T15:43:30.000Z. Sources: 7. Developments: 2.

The Mexican Social Security Institute (IMSS) implemented a mandate requiring employers to use the Tax Administration Service (SAT) e. firma for digital affiliation and administrative procedures. This measure was intended to strengthen security and identity verification, replacing the Electronic Employer Identification Number (NPIE) as the primary access mechanism.

Following this transition, the Association in Industrial Relations of Toluca (ARITAC) issued a warning regarding fraudulent activities. The association reported that unauthorized individuals have been compromising or obtaining digital signatures to impersonate legal representatives. These actors use the stolen credentials to perform unauthorized movements within the IMSS system, creating fraudulent employer registrations and adding workers to company payrolls who are not actually employed by the organizations.

## Timeline

### 2026-09-21: ARITAC warns of fraudulent IMSS employer registrations

ARITAC has warned Mexican companies about a fraud scheme where unauthorized individuals use stolen digital signatures to create fraudulent employer registrations with the IMSS.

5 sources. https://clstr.news/cluster/aritac-warns-of-fraudulent-imss-employer-registrations

### 2026-08-25: IMSS mandates SAT e. firma for employer digital procedures

IMSS now requires the SAT e. firma for employer digital procedures in Mexico to enhance security, while the SAT offers a portable mobile version for easier authentication.

2 sources. https://clstr.news/cluster/imss-mandates-sat-e-firma-for-employer-digital-procedures

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Cite as: IMSS digital authentication and employer fraud. CLSTR, https://clstr.news/situations/imss-digital-authentication-and-employer-fraud