Mount Diablo Unified School District

Mount Diablo Unified School District notified California AG on Oct 20, 2020 of a data breach, which occurred on Sep 14, 2020. Data exposed: Email address, Phone number.

Case file (dates, days to notice against the statute, what the letter offers, prior incidents)

Organization: Mount Diablo Unified School District
Source: California AG · source record
Date reported: Oct 20, 2020
Date(s) of breach: Monday, September 14, 2020
Residents affected: Not published by this source
Data exposed: Email address Phone number
Notice letter: Sample notice (PDF)
Discovered: Sep 14, 2020, as stated in the letter
"On Monday, September 14, 2020, the District was informed that when certain parents were using the SchoolMessenger mobile application, they were able to view a list of roughly thirty (30) unique names, emails, and phone numbers not associ..."
Days to notice: 36 days from discovery (Sep 14, 2020) to the California record (Oct 20, 2020). Statute: 30 days from discovery or notification of the breach (Cal. Civ. Code § 1798.82). Over the statutory period
Third party: The letter attributes the incident to a vendor or service provider
First seen by BreachTally: 2026-10-30 16:09 UTC

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