STOCK TITAN

Cyberattack at iRhythm (NASDAQ: IRTC) involves PHI but no system outage

Filing Impact
(Moderate)
Filing Sentiment
(Neutral)
Form Type
8-K

Rhea-AI Filing Summary

iRhythm Holdings, Inc. reported a material cybersecurity incident after detecting unauthorized activity on certain third-party-hosted business applications on June 8, 2026. A threat actor later claimed to have obtained proprietary data, patient protected health information, and other personal information and demanded payment to avoid disclosure.

The company has confirmed that some data was exfiltrated but, as of this report, has not found any impact on its products, clinical or medical device systems, patient safety, operations, or financial reporting systems. The affected data was accessed via social engineering and did not involve clinical systems or individual financial account or payment card information.

iRhythm is continuing to investigate the nature and scope of the incident and the individuals affected. It currently believes the incident is not reasonably likely to have a material impact on its financial condition or results of operations and notes that it maintains cybersecurity insurance that may cover certain losses.

Positive

  • None.

Negative

  • Material cybersecurity incident with sensitive data exfiltration, including proprietary information and patient protected health information, and an extortion demand from a threat actor, which may create future legal, regulatory, and reputational risks despite no current operational disruption.

Insights

Material data breach with PHI exposure but no current system disruption.

iRhythm has classified this as a material cybersecurity incident involving third-party-hosted business applications. A threat actor claims to hold proprietary data and patient protected health information and has demanded payment, while the company has confirmed some data exfiltration.

Importantly, iRhythm states there is no identified impact to products, clinical or medical device systems, patient safety, or manufacturing and distribution operations as of this report. The company also does not store individual financial account or payment card information, which limits certain fraud-related risks.

The company believes the event is not reasonably likely to have a material impact on financial condition or results of operations, and it maintains cybersecurity insurance. However, future legal, regulatory, or reputational consequences will depend on the final scope of affected data and any subsequent misuse or publication.

Item 1.05 Material Cybersecurity Incidents Business
A cybersecurity incident that the company has determined to be material to investors.
Unauthorized activity identified June 8, 2026 Date iRhythm first detected unauthorized activity
Threat actor communication June 9, 2026 Date of extortion-related communication to iRhythm
Materiality determination date June 10, 2026 Date company determined incident is material
Annual Report reference year 2025 Year-end referenced for additional risk factors
material cybersecurity incident regulatory
"On June 10, 2026, the Company determined that the incident is material in light of the volume of the potentially affected data."
social engineering technical
"the affected data was obtained through social engineering and is from certain third-party-hosted business applications."
Social engineering is the practice of manipulating people into revealing confidential information, granting access, or taking actions that compromise security, often by posing as a trusted person or using urgent, persuasive stories. For investors it matters because these scams can lead to direct financial loss, theft of sensitive corporate data, disrupted operations, or damage to a company’s reputation — similar to a con artist who tricks a business into handing over its keys.
patient protected health information medical
"claiming to have obtained sensitive information, including proprietary data, patient protected health information and other personal information."
cybersecurity insurance financial
"The Company maintains cybersecurity insurance that may cover certain losses associated with the incident"
forward-looking statements regulatory
"This on contains forward-looking statements within the meaning of the federal securities laws"
Forward-looking statements are predictions or plans that companies share about what they expect to happen in the future, like estimating sales or profits. They matter because they help investors understand a company's outlook, but since they are based on guesses and assumptions, they can sometimes be wrong.
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0001388658false00013886582026-06-102026-06-10


  
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549 
FORM 8-K 
CURRENT REPORT
Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934
Date of report (Date of earliest event reported): June 10, 2026
iRhythm Holdings, Inc.
(Exact name of Registrant as specified in its charter) 
Delaware001-3791841-3421287
(State or other jurisdiction of
incorporation or organization)
(Commission
File Number)
(I.R.S. Employer
Identification Number)
699 8th Street, Suite 600
San Francisco, California 94103
(Address of principal executive office) (Zip Code)
(415) 632-5700
(Registrant’s telephone number, including area code)
N/A
(Former Name or Former Address, if Changed Since Last Report)
 
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading SymbolName of each exchange on which registered
Common Stock, Par Value $0.001 Per ShareIRTCThe NASDAQ Global Select Market
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).
Emerging growth company 
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. 
 




Item 1.05 Material Cybersecurity Incidents.

On June 8, 2026, iRhythm Holdings, Inc. (the “Company”) identified unauthorized activity involving data maintained on certain third-party-hosted business applications. The Company promptly activated its cybersecurity response plan and launched an investigation with the support of external advisors and cybersecurity experts to assess and contain the threat.

On June 9, 2026, the Company received communications from a threat actor claiming to have obtained sensitive information, including proprietary data, patient protected health information and other personal information. The communications from the threat actor demanded payment in exchange for not publicly disclosing this information. Since receipt of the communications, the Company has confirmed that certain data was exfiltrated from those applications. On June 10, 2026, the Company determined that the incident is material in light of the volume of the potentially affected data.

Based on its investigation as of the date of this Current Report on Form 8-K, (1) the Company has not identified any impact to its products, clinical or medical device systems, patient safety, manufacturing and distribution operations, financial reporting systems, or the Company’s ability to meet patient needs and (2) the affected data was obtained through social engineering and is from certain third-party-hosted business applications. The incident does not involve the Company’s clinical or medical device systems or connections to customers and the Company does not store or retain individual financial account information or payment card information.

As of the date of this Current Report on Form 8-K, the Company has not identified evidence of ongoing unauthorized access to its systems. The Company is continuing to investigate the nature and scope of the incident, including the categories and volume of the data involved and the individuals affected.

The Company believes, as of the date of this Current Report on Form 8-K, that the incident is not reasonably likely to have a material impact on the Company’s financial condition or results of operations. The Company maintains cybersecurity insurance that may cover certain losses associated with the incident, although there can be no assurance that such coverage will be sufficient to cover all losses the Company may incur.

To the extent any information required by Item 1.05(a) of Form 8-K was not determined or was unavailable at the time of this filing, the Company will amend this Current Report on Form 8-K as such information is determined or becomes available.

Forward-Looking Statements

This Current Report on Form 8-K contains forward-looking statements within the meaning of the federal securities laws, including, without limitation: the Company’s current beliefs, understanding, and expectations regarding the incident; statements regarding the nature and scope of the incident; the Company’s ongoing assessment of the extent, categories and volume of data that was accessed or exfiltrated; the Company’s ongoing efforts to assess and contain the threat, including the Company’s assessment of whether there is any ongoing unauthorized access to its systems; the availability and adequacy of the Company’s insurance coverage; and the reasonably likely impact of the incident on the Company’s business, operations, financial condition and results of operations. These statements are based on current information, estimates and assumptions and are subject to known and unknown risks and uncertainties. Actual results may differ materially from those expressed or implied by these forward-looking statements. Factors that could cause actual results to differ from those expressed in these forward-looking statements include the ongoing assessment of the incident; the potential publication or misuse of affected data by the threat actor or other parties; legal, regulatory, reputational, and financial risks resulting from the incident or additional cybersecurity incidents; and the risks described in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 and subsequent Quarterly Reports on Form 10-Q. Except as required by law, the Company undertakes no obligation to update these statements.



SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

IRHYTHM HOLDINGS, INC.
Date: June 15, 2026
By:/s/ Quentin Blackford
Quentin Blackford
President and Chief Executive Officer


FAQ

What cybersecurity incident did iRhythm Holdings (IRTC) disclose?

iRhythm disclosed a material cybersecurity incident involving unauthorized activity in certain third-party-hosted business applications. A threat actor claimed to have obtained proprietary data, patient protected health information, and other personal information, and the company has confirmed that some data was exfiltrated from those applications.

Did the iRhythm (IRTC) cyber incident affect medical devices or patient safety?

iRhythm states it has not identified any impact on its products, clinical or medical device systems, patient safety, or manufacturing and distribution operations. The incident involves third-party-hosted business applications and does not affect the company’s clinical or medical device systems or customer connections.

What kind of data was involved in iRhythm’s material cybersecurity incident?

According to iRhythm, the threat actor claims to have obtained sensitive information, including proprietary data, patient protected health information, and other personal information. The company is still investigating the exact categories and volume of data involved and which individuals may have been affected.

Is the iRhythm (IRTC) cyber incident expected to impact financial results?

iRhythm currently believes the incident is not reasonably likely to have a material impact on its financial condition or results of operations. The company also maintains cybersecurity insurance that may cover certain losses, although coverage may not fully offset all potential costs.

How did the threat actor gain access in the iRhythm cybersecurity incident?

iRhythm reports that the affected data was obtained through social engineering directed at certain third-party-hosted business applications. As of the date of the report, the company has not identified evidence of ongoing unauthorized access to its systems, but its investigation is continuing.

Does iRhythm (IRTC) store financial account or payment card data affected by the breach?

iRhythm states that it does not store or retain individual financial account information or payment card information. As a result, these specific types of financial data are not involved in the cybersecurity incident described in the report, which may limit related fraud risks.

Filing Exhibits & Attachments

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