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BrazilLogistics and transport2018–2023

ViaQuatro (São Paulo Metro Line 4-Yellow)

Interactive ad doors with facial detection

São Paulo courts fined Metro Line 4 operator ViaQuatro, R$500,000 on appeal in May 2023, over hidden face-detection cameras in ads

StoppedRegulator, audit or court

Problem

ViaQuatro wanted to measure how passengers reacted to advertising on its Yellow Line stations.

Approach

In 2018 the operator installed interactive ad doors with cameras that detected people in front of them and read emotion, gender and age range. Consumer group Idec sued, and a court ordered the cameras switched off in 2018. A 2021 ruling fined the company R$100,000 and barred data collection without consent. In May 2023 the state appeals court raised the collective moral damages to R$500,000. ViaQuatro said the system stored no personal data.

Results

R$ 100,000fine set by the 2021 first-instance rulingRegulator, audit or court[1]
R$ 500,000collective moral damages after the May 2023 appeals ruling, up from R$100,000Regulator, audit or court[2]

Takeaway

The courts found passengers were never told about the cameras, and the data included children and teenagers. The lack of consent and prior notice was the basis for the penalty.

Categories

Business function
Marketing and sales
AI technology
Computer vision
Evidence
Regulator, audit or court

Sources

Source summaries

[1]Idec10 May 2021

Idec, the consumer group that brought the case, reported that the São Paulo court fined ViaQuatro R$100,000 and ordered it not to resume collection without consent. It describes cameras installed in 2018 that detected emotion, gender and age range, and the court's finding that passengers were not informed.

[2]Consumidor Moderno16 May 2023

Consumidor Moderno reported that the 8th Public Law Chamber of the São Paulo state court unanimously upheld the ruling and raised the penalty from R$100,000 to R$500,000. The court cited the lack of notice to passengers and data collected from minors. ViaQuatro said it respected the decision, was considering an appeal and had not stored personal data.

Full details are in the original sources.

Added 25 Oct 2026 · Updated 25 Oct 2026
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