People search Grant Thornton data breach timeline because the brand sits on billions of accounts, credentials, and cloud workloads. BreachHistory indexes 1 Grant Thornton-linked incident, with headline counts up to 6K+ in catalog rows. This page maps every attested event through 2026 with internal links to canonical records.
Why Grant Thornton breach history matters
Grant Thornton operates in Technology (India). Across indexed rows, recurring themes include mixed intrusion and disclosure events. Understanding the chronological pattern helps security teams, customers, and regulators separate confirmed disclosures from forum marketing.
Full timeline through 2026
2023 — unauthorized access to employee email (Apr 19–May 1); ~6.2k consumers in state notices
Cataloged incident. Grant Thornton LLP publicly reported a May 2023 incident in which an unauthorized third party accessed a corporate email mailbox between Apr 19 and May 1, with investigation and Kroll monitoring offered in Massachusetts and other AG filing ecosystems. Exposed categories include Names and personal identifiers; SSNs for a subset per regulatory summaries. BreachHistory cites approximately 6K+ affected records in this row. See the grant-thornton2023email and canonical BreachHistory entry.
Patterns and analysis
- Mixed intrusion and disclosure events — appears across multiple Grant Thornton catalog entries; prioritize controls that address this class of failure.
- Record-count hygiene — BreachHistory indexes actor-cited figures separately from company-confirmed totals; read each row's technicalWriteup before treating counts as fact.
- 2026 monitoring — New disclosures roll into this timeline as they are verified or labeled unverified per catalog policy.
What to do if you may be affected
- Step 1: Enable phishing-resistant MFA on every account tied to this brand.
- Step 2: Use unique passwords and a password manager—breach rows often involve credential reuse.
- Step 3: Monitor official company breach notices and regulator filings, not dark-web downloads.
- Step 4: Review OAuth app permissions and revoke unused third-party integrations.
- Step 5: Bookmark the Grant Thornton company page for new 2026+ disclosures.
Canonical BreachHistory hub
Explore every indexed row: breachhistory.com/grant-thornton · Latest: grant-thornton2023email.
Sources: BreachHistory catalog (1 row for Grant Thornton), company and regulator disclosures cited in individual breach records.