El Camino Health Data Breach: Four Staff Microsoft 365 Accounts Accessed

El Camino Health says it identified unusual activity in its Microsoft 365 system on September 1, 2026. According to the hospital, it immediately secured the system, began an investigation with third-party forensic experts, and notified law enforcement.

The investigation found intermittent unauthorized access to the Microsoft 365 accounts of four employees from August 26 through September 2, 2026, along with documents that were copied or downloaded from those accounts. El Camino Health says its electronic health record system wasn’t involved.

According to the hospital’s letter, the documents may contain names along with contact information, demographic information, Social Security numbers, driver’s license numbers, dates of birth, medical record numbers, patient account numbers, diagnosis, treatment, and prescription information, provider names, dates of service, and health insurance information. What’s included varies from patient to patient.

For some patients, the letter says financial account and routing numbers may also have been involved. Neither the letter nor the hospital’s website notice says whether there’s any evidence the information has been misused.

El Camino Health began mailing letters to affected patients on October 30, 2026, the same day its sample letter was reported to California’s Attorney General. The hospital says its review of the copied documents is still underway and that it will mail letters to any additional patients once that review is finished.

The hospital hasn’t published how many people are involved. Because it filed in California, more than 500 California residents are generally understood to be affected. As of November 11, 2026, we found no El Camino Health filing in Massachusetts, Texas, or Vermont, and none on the federal HHS breach list, whose latest entries date from October 15.

The letter offers a free one-year Experian IdentityWorks Credit 3B membership that includes credit monitoring and $1 million in identity theft insurance, and El Camino Health says enrolling won’t affect your credit score. Its website notice describes the offer as being for people whose Social Security or driver’s license numbers may have been involved. Your letter lists the enrollment deadline and activation code.

The hospital says it has added safeguards and technical security measures to protect and monitor its Microsoft 365 system. Letters began going out about two months after the unusual activity was first spotted.

Because the documents may hold diagnoses, insurance details, and in some cases bank routing numbers, these steps address each kind of risk:

• Enroll in Experian IdentityWorks before the deadline in your letter. You’ll need the activation code printed on it.
• Go through statements from your doctors and health insurer. Look for visits, prescriptions, or services you never received.
• Watch your bank account closely if your letter mentions financial information. Check each statement for withdrawals or transfers you don’t recognize.
• Freeze your credit at Equifax, Experian, and TransUnion. A freeze is free to place and lift, and it stops new credit from being opened in your name while it’s in place.
• Treat unexpected calls, texts, and emails about the incident with suspicion. Verify any outreach independently before responding.

This list is general guidance, not legal advice. A legal professional can explain which protections and rights fit your circumstances.

Did an El Camino Health letter say your Social Security number, medical details, or bank information may have been in the copied documents? Wilshire Law Firm is headquartered in California and handles data breach and consumer protection class actions nationwide. Hospital data breaches that reach many patients are sometimes pursued as class actions. A legal professional from our nationally recognized, award-winning team can review your letter in a free consultation or free case review, available 24/7, and there are no fees unless you get paid.

Contact Wilshire Law Firm about your El Camino Health letter.