Bee Cheng Hiang Marketing Pte Ltd

Background Bee Cheng Hiang Marketing Pte. Ltd. (the “Organisation”) notified the Personal Data Protection Commission (the “Commission”) on 27 April 2026 of a personal data breach involving its bulk marketing email distribution process (the “Incident”). The Incident involved a marketing email sent to the Organisation’s members on 25 April 2026. All email addresses within each batch were displayed in the “To” field, visible to every recipient within that batch, disclosed without the consent of the other recipients. The Organisation established that the Incident was caused by a configuration error in an email distribution Python script developed by one of the Organisation’s employees through the personal use of a generative artificial intelligence (“AI”) tool. The generated script contained a code-level configuration missing a bracket that caused all recipient email addresses within each batch to be grouped together as a single object in the “To” field, rather than as individual, isolated recipient entries. This was not a malfunction in the AI tool but resulted from the prompt given to the AI tool to write a programme to send “mass email using a local list” in batches, without specific instructions to block the visibility of other recipients’ email addresses to each individual recipient. The employee did not realise the error before deploying the script, as testing was done by checking activity logs without reviewing the contents of the actual test email. The erroneous code was: "personalizations": [{"to": [{"email": str(e)} for e in chunk]}] The corrected code is: "personalizations": [{"to": [{"email": str(e)}] } for e in chunk] Code Comparison Table "personalizations": [{"to": [{"email": str(e)} for e in chunk]}] "personalizations": [{"to": [{"email": str(e)}] } for e in chunk] What it means: You are creating one single personalization object that contains an array of