How many people were affected by the Kaiser Foundation Health Plan data breach, and what was exposed?

Kaiser Foundation Health Plan reported that about 13,400,000 people were affected and lists the following information as involved: member names, IP addresses, health-related web activity. Your own letter is the best guide to what was exposed about you, since notices are usually tailored to each person.

What should I do after getting the Kaiser Foundation Health Plan data breach notice?

Keep the letter and the envelope, and note the date it arrived. Freeze your credit with Equifax, Experian and TransUnion, change any passwords the notice mentions, and sign up for any free credit monitoring the letter offers. Then check whether you may have a claim.

Is the Kaiser Foundation Health Plan data breach letter legit or a scam?

A notice from Kaiser Foundation Health Plan in the mail matches the breach Kaiser Foundation Health Plan reported to the CA Attorney General on March 12, 2026, which covers about 13,400,000 people. Check that the company name and dates in your letter match that filing. A real notice of data security incident won't ask for your password, Social Security number or a payment — if it does, contact Kaiser Foundation Health Plan through a phone number or website you find yourself.

Did Kaiser Foundation Health Plan offer free credit monitoring?

Check your letter from Kaiser Foundation Health Plan. If free credit or identity monitoring is offered, the enrollment code and deadline are printed in the notice itself. Because health or insurance details are listed in this filing, also review the benefit statements from your insurer. Enrolling does not give up your right to bring a claim.

Can I sue Kaiser Foundation Health Plan over the data breach?

It depends on what was exposed, the law in CA and your own state, and whether you've been harmed. Most people take part through a class action rather than suing alone. Keep your notification letter — it's the proof that connects you to the breach.

Is there a Kaiser Foundation Health Plan data breach class action lawsuit?

Law firms often open an investigation after a breach notice like this one, and a class action lawsuit may follow. This page doesn't confirm that a lawsuit has been filed against Kaiser Foundation Health Plan. You usually don't have to join a class action to be included — if a settlement is reached, class members are notified and can file a claim.

How much could a Kaiser Foundation Health Plan data breach settlement or claim be worth?

There is no set amount, and no Kaiser Foundation Health Plan settlement is confirmed here. In past data breach settlements, payments depended on what data was exposed and on documented losses — fraud, out-of-pocket costs and time spent dealing with the breach. The filing lists member names, IP addresses, health-related web activity as involved. Keep receipts and records; they're what damages claims are built on.

Do I need a Kaiser Foundation Health Plan data breach lawyer or attorney?

An attorney can read your notice and tell you whether a claim makes sense. A case review here is free, and data breach cases are usually handled on contingency, so there is no upfront cost.

Received a Kaiser Foundation Health Plan notification letter? Read the letter guide

MonitoringCA AG filing · March 12, 2026

Kaiser Foundation Health Plan Reports Member Data Exposure

Kaiser Foundation Health Plan has reported an unauthorized disclosure of member data impacting millions of individuals. Online tracking technologies led to the transmission of member names, IP addresses, and health-related web activity to third-party vendors. This event highlights the importance for affected members to review their personal information and remain vigilant.

State: CA
Affected: 13,400,000
Breach date: April 12, 2024
Reported: March 12, 2026

What may have been exposed

member names
IP addresses
health-related web activity

Kaiser Foundation Health Plan experienced an unauthorized disclosure of data, which occurred on April 12, 2024. This event involved the transmission of certain member information through online tracking tools.

The types of information reported as exposed include member names, IP addresses, and health-related web activity. This data was transmitted to specific third-party vendors without authorization.

Approximately 13,400,000 individuals were affected by this incident. The details of this event were filed with the California Attorney General's office on March 12, 2026.

Individuals who may have been impacted should consider reviewing any official notifications received from Kaiser Foundation Health Plan. It is also generally advisable to be aware of unsolicited communications that might request personal details.

This information is based on public disclosures filed with regulatory authorities. The investigation into this matter is currently noted as being in a monitoring status.

What to do if you were affected

Based on the categories of information reported in this filing, these steps can help limit the risk of identity theft and fraud.

Check for medical identity theft
Review the Explanation of Benefits statements from your health insurer for services or claims you never received, which can signal misuse of your medical identity.
Stay alert to targeted scams
Be cautious of calls, texts, or emails that reference this breach. Legitimate organizations won't ask you to confirm sensitive details through an unsolicited message.
Keep your notification letter
Save the notice you received. It documents that your information was involved and is often needed to enroll in any credit monitoring offered or to join a related legal claim.

What to know about the Kaiser Foundation Health Plan data breach

How many people were affected by the Kaiser Foundation Health Plan data breach, and what was exposed?: Kaiser Foundation Health Plan reported that about 13,400,000 people were affected and lists the following information as involved: member names, IP addresses, health-related web activity. Your own letter is the best guide to what was exposed about you, since notices are usually tailored to each person.
What should I do after getting the Kaiser Foundation Health Plan data breach notice?: Keep the letter and the envelope, and note the date it arrived. Freeze your credit with Equifax, Experian and TransUnion, change any passwords the notice mentions, and sign up for any free credit monitoring the letter offers. Then check whether you may have a claim.
Is the Kaiser Foundation Health Plan data breach letter legit or a scam?: A notice from Kaiser Foundation Health Plan in the mail matches the breach Kaiser Foundation Health Plan reported to the CA Attorney General on March 12, 2026, which covers about 13,400,000 people. Check that the company name and dates in your letter match that filing. A real notice of data security incident won't ask for your password, Social Security number or a payment — if it does, contact Kaiser Foundation Health Plan through a phone number or website you find yourself.
Did Kaiser Foundation Health Plan offer free credit monitoring?: Check your letter from Kaiser Foundation Health Plan. If free credit or identity monitoring is offered, the enrollment code and deadline are printed in the notice itself. Because health or insurance details are listed in this filing, also review the benefit statements from your insurer. Enrolling does not give up your right to bring a claim.
Can I sue Kaiser Foundation Health Plan over the data breach?: It depends on what was exposed, the law in CA and your own state, and whether you've been harmed. Most people take part through a class action rather than suing alone. Keep your notification letter — it's the proof that connects you to the breach.
Is there a Kaiser Foundation Health Plan data breach class action lawsuit?: Law firms often open an investigation after a breach notice like this one, and a class action lawsuit may follow. This page doesn't confirm that a lawsuit has been filed against Kaiser Foundation Health Plan. You usually don't have to join a class action to be included — if a settlement is reached, class members are notified and can file a claim.
How much could a Kaiser Foundation Health Plan data breach settlement or claim be worth?: There is no set amount, and no Kaiser Foundation Health Plan settlement is confirmed here. In past data breach settlements, payments depended on what data was exposed and on documented losses — fraud, out-of-pocket costs and time spent dealing with the breach. The filing lists member names, IP addresses, health-related web activity as involved. Keep receipts and records; they're what damages claims are built on.
Do I need a Kaiser Foundation Health Plan data breach lawyer or attorney?: An attorney can read your notice and tell you whether a claim makes sense. A case review here is free, and data breach cases are usually handled on contingency, so there is no upfront cost.

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