# On the Privacy of the Opal Data Release: A Response

## TL;DR

This paper responds to concerns about the privacy implications of releasing the Opal public transport dataset, which contains detailed tap-on/tap-off data of individuals over two weeks.

## Contribution

It provides a detailed analysis and response regarding the privacy risks associated with the Opal dataset release.

## Key findings

- Identified potential privacy risks in the dataset
- Discussed privacy-preserving considerations for public data releases
- Highlighted the need for careful data anonymization

## Abstract

This document is a response to a report from the University of Melbourne on the privacy of the Opal dataset release. The Opal dataset was released by Data61 (CSIRO) in conjunction with the Transport for New South Wales (TfNSW). The data consists of two separate weeks of "tap-on/tap-off" data of individuals who used any of the four different modes of public transport from TfNSW: buses, light rail, train and ferries. These taps are recorded through the smart ticketing system, known as Opal, available in the state of New South Wales, Australia.