INSP

insp-202602050001609550False12/3100016095502026-02-052026-02-05

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): February 5, 2026

INSPIRE MEDICAL SYSTEMS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3846826-1377674 (State or other jurisdiction of incorporation)(Commission File Number)(I.R.S. Employer Identification No.)

5500 Wayzata Blvd., Suite 1600 Golden Valley, Minnesota 55416 (Address of principal executive offices) (Zip Code)

(844) 672-4357 (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 Symbol(s)Name of each exchange on which registered Common Stock, $0.001 par value per shareINSPNew York Stock Exchange

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 2.02.    Results of Operations and Financial Condition.

On February 11, 2026, Inspire Medical Systems, Inc. (the “Company”) issued a press release announcing its financial results for the quarter and full year ended December 31, 2025. The full text of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference. The information in this Item 2.02 of this Current Report on Form 8-K (and in the press release attached as Exhibit 99.1 hereto) shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall it be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 5.03    Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year.

The Company intends to put forth a proposal at the Company’s annual meeting of stockholders to be held in 2026 (the “2026 Annual Meeting”) to amend its Seventh Amended and Restated Certificate of Incorporation in order to declassify its Board of Directors (the “Board”) and provide for the annual election of directors following a phase-in period (the “Proposed Charter Amendment”). In connection with the Proposed Charter Amendment, on February 5, 2026, the Board approved the Amended and Restated Bylaws of the Company (the “Amended Bylaws”), subject to and effective upon the approval of the Proposed Charter Amendment by the stockholders at the Company’s 2026 Annual Meeting. The Amended Bylaws would remove the provision providing that directors may be removed only for cause. Instead, removals would be governed by the Proposed Charter Amendment which would follow applicable Delaware General Corporation Law.

The Amended Bylaws, along with a copy marked to show the changes from the Company’s Amended and Restated Bylaws as in effect prior to the Amended Bylaws, are filed herewith as Exhibits 3.1 and 3.2, respectively. The above description of the changes contained in the Amended Bylaws is qualified by reference to the full text of the Amended Bylaws, which are incorporated herein by reference.

Item 7.01.    Regulation FD Disclosure.

In February and March of 2026, the Company will be participating in various meetings with investors and analysts, and a copy of the Company’s presentation materials being used at these meetings is furnished as Exhibit 99.2 hereto and is incorporated herein by reference. These presentation materials are also available on the Investor Relations page of the Company’s website at https://investors.inspiresleep.com. The information in this Item 7.01 of this C

insp-202601090001609550False00016095502026-01-092026-01-09

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): January 9, 2026

INSPIRE MEDICAL SYSTEMS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3846826-1377674 (State or other jurisdiction of incorporation)(Commission File Number)(I.R.S. Employer Identification No.)

5500 Wayzata Blvd., Suite 1600 Golden Valley, Minnesota 55416 (Address of principal executive offices) (Zip Code)

(844) 672-4357 (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 Symbol(s)Name of each exchange on which registered Common Stock, $0.001 par value per shareINSPNew York Stock Exchange

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 2.02. Results of Operations and Financial Condition.

On January 12, 2026, Inspire Medical Systems, Inc. (the “Company”) issued a press release announcing certain preliminary and unaudited results for the quarter and full year ended December 31, 2025. These preliminary financial results are based on the Company’s current estimate of its results for the year ended December 31, 2025, and remain subject to change based on the completion of closing and review procedures and the execution of the Company’s internal control over financial reporting. The full text of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

The information in this Item 2.02 of this Current Report on Form 8-K (and in the press release attached as Exhibit 99.1 hereto) shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall it be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On January 9, 2026, the Board of Directors of the Company approved the appointment of Matthew J. Osberg as Chief Financial Officer, effective as of the day after the Company files its Annual Report on Form 10-K for the fiscal year ended December 31, 2025 (the “2025 10-K”). As Chief Financial Officer, Mr. Osberg will also serve as the Company’s principal financial officer and principal accounting officer, effective as of such date.

Mr. Osberg, age 50, previously served as Executive Vice President and Chief Financial Officer at Apogee Enterprises, Inc., a publicly traded manufacturer of architectural building products and services, from April 2023 to January 2026. Earlier in his career, Mr. Osberg served as Chief Financial Officer at Helen of Troy Limited, a publicly traded global consumer products company, from November 2021 to April 2023 and Senior Vice President of Corporate Finance at Helen of Troy Limited from 2016 to 2021. Prior to this, he held senior finance leadership roles at Best Buy Co., Inc. and worked at Ernst & Young from 1998 to 2008. Mr. Osberg holds a bachelor’s degree in accounting from Augsburg University and is a Certified Public Accountant (inactive).

There is no arrangement or understanding between Mr. Osberg and any other person pursuant to which Mr. Osberg was appointed as an officer of the Company. There are no relationships, family or otherwise, between Mr. Osberg and the C

insp-202511030001609550False00016095502025-11-032025-11-03

SECURITIES AND EXCHANGE

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): November 3, 2025

INSPIRE MEDICAL SYSTEMS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3846826-1377674 (State or other jurisdiction of incorporation)(Commission File Number)(I.R.S. Employer Identification No.)

5500 Wayzata Blvd., Suite 1600 Golden Valley, Minnesota 55416 (Address of principal executive offices) (Zip Code)

(844) 672-4357 (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 Symbol(s)Name of each exchange on which registered Common Stock, $0.001 par value per shareINSPNew York Stock Exchange

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 2.02.    Results of Operations and Financial Condition.

On November 3, 2025, Inspire Medical Systems, Inc. (the “Company”) issued a press release announcing its financial results for the quarter ended September 30, 2025. The full text of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

Item 7.01.     Regulation FD Disclosure. In November and December of 2025, the Company will be participating in various meetings with investors and analysts, and a copy of the Company’s presentation materials being used at these meetings is furnished as Exhibit 99.2 hereto and is incorporated herein by reference. These presentation materials are also available on the Investor Relations page of the Company’s website at https://investors.inspiresleep.com.

The information in each of Item 2.02 and Item 7.01 of this Current Report on Form 8-K and in the press release attached as Exhibit 99.1 and the presentation attached as Exhibit 99.2 shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall it be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description

99.1Press release of Inspire Medical Systems, Inc., dated November 3, 2025.

99.2Inspire Medical Systems, Inc. Presentation, November 3, 2025.

104Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document.

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SIGNATURES

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

INSPIRE MEDICAL SYSTEMS, INC.

Date:November 3, 2025By:/s/ Richard J. Buchholz Richard J. Buchholz Chief Financial Officer

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