Stockton Cardiology Medical Group notified patients of a data breach on March 9, 2026. On December 15, 2025, suspicious emails were identified. On January 17, 2026, it was discovered that an unauthorized individual accessed and removed files containing PHI and PII. On February 17, 2026, some files were publicly disclosed. The group engaged a security firm, shut down remote access, added MFA, and reset passwords. Credit monitoring is offered.