8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of the SecuritiesExchange Act of 1934

Date of Report (Date of earliest event reported): December 18, 2025

Compass Minerals International, Inc.

(Exact name of registrant as specified in its charter)

Delaware	001-31921	36-3972986
(State<br> or other jurisdiction of incorporation)	(Commission<br> File Number)	(I.R.S.<br> Employer<br><br> Identification No.)

9900 West 109^th^ Street

Suite 100

Overland Park, KS 66210

(Address of principal executive offices)

(913) 344-9200

(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 class	Trading Symbol	Name of each exchange on which registered
Common stock, $0.01 par value	CMP	The New 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 5.02 Departure of Directors or CertainOfficers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Effective December 18, 2025, the Board of Directors (the “Board”) of Compass Minerals International, Inc. (the “Company”) increased the size of the Board from eight to 12 directors and appointed Russell Ball, Denise Merle, Mark Roberts and David Safran to the Board, each with a term expiring at the Company’s 2026 annual meeting of stockholders (the “2026 Annual Meeting”), as part of a Board refreshment initiative.

Mr. Ball has been appointed to the Audit Committee and the newly established Capital Allocation and Technical Committee (the “CAT Committee”); Ms. Merle has been appointed to the Audit Committee, Compensation Committee and Nominating and Corporate Governance Committee (the “NCG Committee”); Mr. Roberts has been appointed to the Environmental, Health, Safety and Sustainability Committee (the “EHSS Committee”), the NCG Committee and the CAT Committee; and Mr. Safran has been appointed to the EHSS Committee and the CAT Committee.

As non-employee directors, each new director will be entitled to receive the same compensation as the Company’s other non-employee directors, as described in the Summary of Non-Employee Director Compensation, as of January 1, 2026, which is attached as Exhibit 10.30 to the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2025, and in accordance with the Company’s Non-Employee Director Compensation Policy, which is attached as Exhibit 10.1 to the Company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2020. In addition, each new director will receive an equity grant, vesting on the first anniversary of the grant, with an equity value equal to a portion of $120,000 (the annual equity award value paid to the Company’s non-employee directors), prorated based on the number of days each new director will serve in advance of the anticipated date of the Company’s 2026 Annual Meeting. Each new director will enter into the Company’s standard form of indemnification agreement with the Company.

There are no arrangements or understandings between any of Mr. Ball, Ms. Merle, Mr. Roberts, and Mr. Safran and any other person pursuant to which they will join the Board. Mr. Safran is President and Chief Executive Officer of Innovative Surface Solutions (“Innovative”). Since the beginning of our last fiscal year, the Company has purchased salt-treatment materials from Innovative in a total amount of approximately USD $3,170,000. As a result of such transactions, the Board has determined that Mr. Safran is not an independent director. Other than as disclosed above, there are no transactions between Mr. Ball, Ms. Merle, Mr. Roberts or Mr. Safran and the Company that would be required to be reported under Item 404(a) of Regulation S-K.

In connection with the Board refreshment initiative, on December 18, 2025, Lori Walker, Vance Holtzman and Shane Wagnon each notified the Company that they will not be standing for reelection to the Board at the Company’s 2026 Annual Meeting, and Joe Reece notified the Company that while he will stand for reelection at the Company’s 2026 Annual Meeting, he does not intend to seek reelection at the Company’s 2027 annual meeting of stockholders (the “2027 Annual Meeting”). The Company expects to reduce the size of the Board to nine directors effective at the 2026 Annual Meeting, and then further reduce the size of the Board back to eight directors at or before the 2027 Annual Meeting. None of Mr. Holtzman’s, Mr. Wagnon, Mr. Reece’s or Ms. Walker’s decisions not to stand for reelection resulted from any disagreement with the Company.

Item 7.01 Regulation FD Disclosure

On December 18, 2025, the Company issued a press release announcing the Board refreshment initiative, associated changes in Board composition and the creation of the new CAT Committee. The press release is attached as Exhibit 99.1 and is incorporated by reference.

The information contained in this Item 7.01 and Exhibit 99.1 is being furnished and 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, or incorporated by reference in any filing under the Securities Act or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits

(d) Exhibits

Exhibit No.	Exhibit Description
99.1	Press Release issued by Compass Minerals International, Inc. on December 18, 2025
104	Cover Page Interactive Data File (embedded within the Inline XBRL document).

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.

	COMPASS MINERALS INTERNATIONAL, INC.
Date: December 18, 2025	By:	/s/ Peter Fjellman
		Name: Peter Fjellman
		Title: Chief Financial Officer

Exhibit 99.1

FOR IMMEDIATE RELEASE

Compass MineralsAnnounces

Additions toBoard of Directors

OVERLAND PARK, Kan. (Dec. 18, 2025) – Compass Minerals (NYSE: CMP), a leading global provider of essential minerals, today announced the company’s board of directors (the board) appointed four new directors as part of a board refreshment initiative.

Joe Reece, non-executive chair of the board, commented, “The addition of these directors further enhances the expertise on the board to support the company as it focuses on its core Salt and Plant Nutrition businesses. Importantly, the additions bring more specific domain expertise to support the company’s back-to-basics strategy. They bring deep knowledge and experience in industrial and manufacturing businesses, and in some cases have direct experience in the salt and plant nutrition industries. I’m confident that they will complement our board and leadership team and help accelerate the progress being made to improve the performance and profitability of the business.”

Compass Minerals has expanded the size of its board from eight to 12 directors to accommodate these appointments.

In addition to the new board appointments, the board has established an additional committee, the Capital Allocation and Technical (CAT) Committee, to further support the focus on the company’s core business operations.

The newly appointed directors were identified and selected in connection with a search process conducted by the Nominating/Corporate Governance (NCG) Committee, with the assistance of a third-party search firm.

Below are brief biographies of the newly appointed directors:

·	Russell<br> Ball – Mr. Ball is a retired mining executive who currently provides consulting<br> and advisory services across the extractive industries. He brings more than 30 years of mining<br> experience to the board, including serving as president and CEO of Calibre Mining Corporation<br> (now Equinox Gold) and executive vice president and chief financial officer of both Newmont<br> Mining Corporation (Newmont) and Goldcorp Inc. (the latter subsequently acquired by Newmont).<br> Mr. Ball will serve on the Audit Committee and become its chair after the 2026 annual<br> meeting. Additionally, Mr. Ball will serve on the CAT Committee.
·	Denise<br> Merle – Ms. Merle currently serves as senior vice president, chief administration<br> officer and chief human resources officer for Weyerhaeuser Company, a global timber REIT<br> and wood products manufacturing company. In her over 25-year career at the company, she has<br> held leadership positions overseeing human resources, finance and audit, and corporate governance<br> and sustainability. Ms. Merle will serve on the Audit, NCG and Compensation Committees.
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·	Mark<br> Roberts – Mr. Roberts is currently serving as operating advisor at White Mountain<br> Partners, Inc., a firm providing institutional capital to companies in the essential<br> services, light industrial and specialty consumer industries. He has nearly 30 years of experience<br> leading global salt and potash businesses, including serving as CEO at Morton Salt and chief<br> operating officer at K+S AG, a leading global potash producer. Mr. Roberts will serve<br> on the Environmental, Health, Safety and Sustainability (EHS&S) Committee and will become<br> its chair after the 2026 annual meeting. Additionally, Mr. Roberts will serve on the<br> NCG and CAT Committees.
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·	David<br> Safran – Mr. Safran is currently president and CEO of Innovative Surface Solutions<br> LP, a provider of advanced surface treatment technologies and solutions. He has 25 years<br> of experience in corporate finance and business strategy roles, including serving as the<br> CEO of Kissner Group, a North American manufacturer and distributor of bulk rock salt and<br> packaged specialty deicing products. Mr. Safran will serve on the EHS&S and CAT<br> Committees.
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Current directors representing the company’s largest shareholder, Koch Minerals & Trading, LLC, a subsidiary of Koch, Inc. (Koch), Vance Holtzman and Shane Wagnon are expected to complete their current term on the board and do not intend to stand for reelection at the company’s 2026 annual meeting. In a statement from Mr. Holtzman and Mr. Wagnon, “Koch is supportive of the back-to-basics strategy being pursued by Compass Minerals and the associated focus on advancing organizational and operational efficiencies, improving profitability, and deleveraging the balance sheet. While Koch has a contractual right to appoint representatives to the Compass Minerals board, Koch has determined that it is appropriate to not stand for reelection at the next annual meeting, given the extremely strong board slate identified through this search process. We believe the skillsets and experiences of the incoming directors align well with the company’s strategy. Koch remains a large shareholder and will continue to evaluate opportunities to assist and support the company in areas where our capabilities can provide mutual benefit.”

The company expects to reduce the size of the board to nine directors, effective at the 2026 annual meeting.

Consistent with the company’s governance guidelines regarding term limits, Lori Walker, the current Audit Committee chair and a board member since 2015, will not stand for reelection at the company’s 2026 annual meeting. The board wishes to thank Ms. Walker for her service and contributions to Compass Minerals.

To facilitate an orderly transition in the coming year, the current non-executive board chair Joe Reece will stand for reelection at the company’s 2026 annual meeting and is then expected to transition from the role at some point during the fiscal year, at which point it is expected that he would step off the board and that the company would reduce the size of the board to eight directors.

About CompassMinerals

Compass Minerals (NYSE: CMP) is a leading global provider of essential minerals focused on safely delivering where and when it matters to help solve nature’s challenges for customers and communities. The company’s salt products help keep roadways safe during winter weather and are used in numerous other consumer, industrial, chemical and agricultural applications. Its plant nutrition products help improve the quality and yield of crops while supporting sustainable agriculture. Compass Minerals operates 12 production and packaging facilities with more than 1,800 employees throughout the U.S., Canada and the U.K. Visit compassminerals.com for more information about the company and its products.

Investor Contact	Media Contact
Brent Collins	Kevin Gabriel
Vice President, Treasurer & Investor Relations	Senior Director, Corporate Affairs
+1.913.344.9111	+1.913.344.9265
InvestorRelations@compassminerals.com	MediaRelations@compassminerals.com