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Borrowings | 12 Months Ended
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Dec. 31, 2025
Borrowings [Abstract] |
Borrowings | Borrowings Debt (excluding convertible debt) consists of the following (in millions):
| December 31, 2025 |  | December 31, 2024
2021 Credit Agreement | $ | 450.0 |  |  | $ | 694.6 |
Other | 1.6 |  |  | 2.8 |
Total debt | 451.6 |  |  | 697.4 |
Less: debt, current | (1.6) |  |  | (1.2) |
Less: deferred financing costs | (6.9) |  |  | (11.0) |
Debt, non-current | $ | 443.1 |  |  | $ | 685.2 |
As of December 31, 2025, and December 31, 2024, the fair market value of the Company’'s 2021 Credit Agreement was $452.3 million and $696.3 million, respectively. The fair market value for the 2021 Credit Agreement was estimated using primarily level 2 inputs, including borrowing rates available to the Company at the respective period ends. The fair market value for the Company’s remaining debt approximates the respective carrying amounts as of December 31, 2025, and December 31, 2024. 2021 Credit Agreement The Company maintains a credit agreement (the “2021 Credit Agreement”) among Mirion IntermediateCo Inc., a Delaware corporation, as Holdings, Mirion Technologies (US Holdings), Inc., as the Parent Borrower, Mirion Technologies (US), Inc., as the Subsidiary Borrower, the lending institutions party thereto, and Citibank, N.A., as the Administrative Agent and Collateral Agent. The 2021 Credit Agreement provides for an $830.0 million senior secured first lien term loan facility and a $175.0 million senior secured revolving facility (collectively, the “Credit Facilities”). The term loan facility is scheduled to mature on June 5, 2032, and the revolving facility is scheduled to expire and mature on March 21, 2030. The agreement requires the payment of a commitment fee of 0.50% per annum for unused revolving commitments, subject to stepdowns to 0.375% per annum and 0.25% per annum upon the achievement of specified leverage ratios. Any outstanding letters of credit issued under the 2021 Credit Agreement reduce the availability under the revolving line of credit. The 2021 Credit Agreement is secured by a first priority lien on the equity interests of the Parent Borrower owned by Holdings and substantially all of the assets (subject to customary exceptions) of the borrowers and the other guarantors thereunder. Interest with respect to the facilities is based on, at the option of the borrowers, (i) a customary base rate formula for borrowings in U.S. dollars or (ii) a floating rate formula based on LIBOR (with customary fallback provisions) for borrowings in U.S. dollars, a floating rate formula based on Euro Interbank Offered Rate (“EURIBOR”) for borrowings in Euro or a floating rate formula based on SONIA for borrowings in Pounds Sterling, each as described in the 2021 Credit Agreement with respect to the applicable type of borrowing. The 2021 Credit Agreement included fallback language that seeks to either facilitate an agreement with the Company’s lenders on a replacement rate for LIBOR in the event of its discontinuance or that automatically replaces LIBOR with benchmark rates based upon the Secured Overnight Financing Rate (“SOFR”) or other benchmark replacement rates upon certain triggering events. On June 23, 2023, the 2021 Credit Agreement was amended, among other things, to replace the interest rate based on LIBOR and related LIBOR-based mechanics applicable to U.S. Dollar borrowings under the Credit Agreement with an interest rate based on SOFR (including, solely with respect to currently outstanding term loans, a customary spread adjustment of 0.11448%, 0.26161%, and 0.42826% for borrowing with interest periods of 1, 3, and 6 months, respectively) and related SOFR-based mechanics. The 2021 Credit Agreement contains customary representations and warranties as well as customary affirmative and negative covenants and events of default. The negative covenants include, among others and in each case subject to certain thresholds and exceptions, limitations on incurrence of liens, limitations on incurrence of indebtedness, limitations on making dividends and other distributions, limitations on engaging in asset sales, limitations on making investments, and a financial covenant that the “First Lien Net Leverage Ratio” (as defined in the 2021 Credit Agreement) as of the end of any fiscal quarter is not greater than 7.00 to 1.00 if on the last day of such fiscal quarter certain borrowings outstanding under the revolving credit facility exceed 40% of the total revolving credit commitments at such time. The covenants also contain limitations on the activities of Mirion IntermediateCo, Inc. as the “passive” holding company. If any of the events of default occur and are not cured or waived, any unpaid amounts under the 2021 Credit Agreement may be declared immediately due and payable, the revolving credit commitments may be terminated and remedies against the collateral may be exercised. Mirion IntermediateCo, Inc. was in compliance with all debt covenants on December 31, 2025 and December 31, 2024. Term Loan - The term loan initially had a seven-year term (expiring October 2028) and bore interest at the greater of LIBOR (through June 30, 2023) / SOFR (subsequent to June 30, 2023 through May 21, 2024) or 0.50%, plus 2.75%. On May 22, 2024, the Company entered into Amendment No. 3 (“Amendment No. 3”) to the Credit Agreement. Amendment No. 3 reduced the applicable margin rate on the term loans from 2.75% to 2.25% and reduced the credit spread based upon rate term to 0%, with other terms and conditions remaining consistent (effectively the existing loan was refinanced). Amendment No. 3 was accounted for prospectively as a debt modification in accordance with ASC 470-50, Debt—Modifications and Extinguishments. On June 5, 2025, the Company entered into Amendment No. 5 to the 2021 Credit Agreement (“Amendment No. 5”). Under Amendment No. 5, the Company utilized funds from the private offering of Convertible Senior Notes due 2030 completed on May 23, 2025 (see Note 9, Convertible Debt) to repay $244.6 million in outstanding principal and $8.3 million in accrued interest as well as to extend the maturity date of the term loan to June 5, 2032 (collectively, the “June 2025 Refinancing”). The June 2025 Refinancing was accounted for as a partial extinguishment and partial modification of the term loan debt. The Company accounted for $244.6 million of the term loan principal as an extinguishment of debt; the remaining $450.0 million of principal was accounted for as a modification to the extent the principal holdings at the syndicated lender level remained unchanged. As a result, the Company recorded a loss on partial debt extinguishment of $5.8 million within the Consolidated Statement of Operations for the period ended December 31, 2025 attributed to the derecognition of a proportionate amount of unamortized deferred financing costs. On December 8, 2025, the Company entered into Amendment No. 6 to the 2021 Credit Agreement (“Amendment No. 6”). Amendment No. 6 reduced the applicable margin rate on the term loans from 2.25% to 2.00%, with other terms and conditions remaining consistent (effectively the existing loan was refinanced). Amendment No. 6 was accounted for prospectively as a debt modification in accordance with ASC 470-50, Debt—Modifications and Extinguishments. The interest rate was 5.78% and 6.85% as of December 31, 2025, and December 31, 2024, respectively. The Company repaid $244.6 million and zero for the period ended December 31, 2025, and the period ended December 31, 2024, respectively. Revolving Line of Credit - The revolving line of credit arrangement initially had a five year term (expiring October 2026) and bore interest at the greater of LIBOR (through June 30, 2023) / SOFR (subsequent to June 2023) or 0%, plus 2.25%. The terms of the revolving line of credit were amended on March 21, 2025, through Amendment No. 4 to the 2021 Credit Agreement (“Amendment No. 4”). Under Amendment No. 4, revolving credit commitments from lenders increased from $90.0 million to $175.0 million, and the maturity date extended to March 21, 2030, subject to a “springing” maturity date that is 91 days prior to the maturity date of the outstanding term loan under the 2021 Credit Agreement (but only to the extent the outstanding principal amount of the term loan exceeds $100.0 million on the date of determination, and a final statement maturity date that is early than 91 days after March 21, 2030). The 2021 Credit Agreement requires the payment of a commitment fee of 0.25% per annum for unused commitments. Any outstanding letters of credit reduce the availability of the revolving line of credit. There was no outstanding balance under the arrangement as of December 31, 2025, and December 31, 2024. Additionally, the Company has standby letters of credit issued under its 2021 Credit Agreement that reduce the availability under the revolver of $15.7 million and $17.9 million as of December 31, 2025, and December 31, 2024, respectively. The amount available on the revolver as of December 31, 2025, and December 31, 2024 was approximately $159.3 million and $72.1 million, respectively. Deferred Financing Costs In connection with the issuance of the 2021 Credit Agreement term loan, we incurred debt issuance costs of $21.7 million on date of issuance. In accordance with accounting for debt issuance costs, we recognize and present deferred finance costs associated with non-revolving debt and financing obligations as a reduction from the face amount of related indebtedness in our consolidated balance sheets. In connection with the issuance of the 2021 Credit Agreement revolving line of credit, we incurred debt issuance costs of $1.8 million. We recognize and present debt issuance costs associated with revolving debt arrangements as an asset and include the deferred finance costs within other assets on our consolidated balance sheets. We amortize all debt issuance costs over the life of the related indebtedness. In connection with the May 22, 2024 closing of the refinanced Credit Facilities on the term loan, the Company determined the change would be accounted for prospectively as a debt modification in accordance with ASC 470-50, Debt—Modifications and Extinguishments. As a result, the Company capitalized an additional $1.3 million for the payment of upfront lender fees. In connection with the March 21, 2025 refinancing of the revolving line of credit under the 2021 Credit Agreement, the Company determined the change would be accounted for prospectively as a debt modification in accordance with ASC 470-50, Debt—Modifications and Extinguishments. As a result, the Company capitalized an additional $0.8 million for the payment of upfront lender fees. In connection with the June 5, 2025 closing of the refinanced Credit Facilities, the Company determined the change would be accounted for prospectively as a partial debt extinguishment in accordance with ASC 470-50, Debt—Modifications and Extinguishments. As a result, the Company expensed $5.0 million of the remaining deferred financing costs associated with the debt prior to the June 2025 Refinancing of the Credit Facilities and a portion of the arrangement fees for the new debt of $0.8 million as a loss on partial debt extinguishment. The remaining arrangement fees for the new debt of $2.1 million were capitalized as debt issuance fees, and the remaining transaction costs of $1.1 million were allocated consistently with ASC 470-50, with $0.8 million expensed as incurred and the remaining $0.3 million capitalized as debt issuance fees. Prior to the June 2025 Refinancing, there was approximately $9.6 million of deferred issuance fees remaining to be amortized. As a result of Amendment No. 5, the partial extinguishment and modification resulted in a net reduction in deferred issuance fees of $2.6 million with a new balance of $7.0 million in debt issuance fees capitalized to be amortized over the life of the remaining debt. For the fiscal years ended December 31, 2025, and December 31, 2024, we incurred approximately $10.0 million (including a $5.8 million loss on partial debt extinguishment for the $244.6 million early debt repayment) and $3.1 million, respectively, of amortization expense of the deferred financing costs. Overdraft Facilities The Company has overdraft facilities with certain German and French financial institutions. As of December 31, 2025, and December 31, 2024, there were no outstanding amounts under these arrangements. Accounts Receivable Sales Agreement We are party to an agreement to sell short-term receivables from certain qualified customer trade accounts to an unaffiliated French financial institution without recourse. Under this agreement, the Company can sell up to €12.4 million ($14.6 million) and €12.5 million ($13.0 million) as of December 31, 2025, and December 31, 2024, respectively, of eligible accounts receivables. The accounts receivable under this agreement are sold at face value and are excluded from the consolidated balance if revenue has been recognized on the related receivable. When the related revenue has not been recognized on the receivable the Company considers the accounts receivable to be collateral for short-term borrowings. As of December 31, 2025, and December 31, 2024, there was approximately $0.0 million and $0.2 million, respectively, outstanding under these arrangements included as Other in the Borrowings table above. Total costs associated with this arrangement were immaterial for the fiscal years ended December 31, 2025, 2024, and 2023, and are included in selling, general and administrative expense in the consolidated statements of operations. Performance Bonds and Other Credit Facilities The Company has entered into various line of credit arrangements with local banks in France and Germany. These arrangements provide for the issuance of documentary and standby letters of credit of up to €73.5 million ($85.4 million) and €72.6 million ($75.4 million) as of December 31, 2025, and December 31, 2024, respectively, subject to certain local restrictions. As of December 31, 2025 and December 31, 2024, €37.3 million ($43.9 million) and €56.0 million ($58.2 million), respectively, of the lines had been utilized to guarantee documentary and standby letters of credit, with interest rates ranging from 0.5% to 2.0%. In addition, the Company posts performance bonds with irrevocable letters of credit to support certain contractual obligations to customers for equipment delivery. These letters of credit are supported by restricted cash accounts, which totaled $2.9 million and $0.4 million as of December 31, 2025 and December 31, 2024, respectively. At December 31, 2025, contractual principal payments of total borrowings are as follows (in millions):
Fiscal year ending December 31: |
2026 | $ | 1.6 |
2027 | — |
2028 | — |
2029 | — |
2030 | — |
Thereafter | 450.0 |
Gross Payments | 451.6 |
Unamortized debt issuance costs | (6.9) |
Total borrowings, net of debt issuance costs | $ | 444.7 |
Convertible Debt Convertible debt consists of the following (in millions):
| December 31, 2025 |  | December 31, 2024
2030 notes | $ | 400.0 |  |  | $ | — |
2031 notes | 375.0 |  |  | — |
Total convertible debt | 775.0 |  |  | — |
Less: deferred financing costs | (20.5) |  |  | — |
Convertible debt | $ | 754.5 |  |  | $ | — |
Convertible Senior Notes due 2030 On May 23, 2025, the Company comple ted a private offering of $400.0 million in aggregate principal amount of 0.25% Convertible Senior Notes due 2030, including the initial purchasers’ exercise in full of their option to purchase additional Notes (the “2030 Notes”). The 2030 Notes were issued pursuant to an indenture, dated May 23, 2025 (the “May Indenture”). The May Indenture includes customary covenants and sets forth certain events of default after which the 2030 Notes may be declared immediately due and payable and sets forth certain types of bankruptcy or insolvency events of default involving the Company after which the outstanding principal and accrued interest of the 2030 Notes becomes automatically due and payable. The 2030 Notes will mature on June 1, 2030, unless earlier converted, redeemed or repurchased. The 2030 Notes will bear interest from May 23, 2025 at a rate of 0.25% per year payable semiannually in arrears on June 1 and December 1 of each year, beginning on December 1, 2025. The 2030 Notes will be convertible at the option of the holders in certain circumstances discussed below. The 2030 Notes will be convertible into cash, shares of Mirion’s Class A common stock or a combination of cash and shares of Mirion’s Class A common stock, at the Company’s election. The initial conversion rate is 43.2751 shares of Mirion’s Class A common stock per $1,000 principal amount of 2030 Notes, which is equivalent to an initial conversion price of approximately $23.11 per share of Mirion's Class A common stock. The initial conversion price of the 2030 Notes represents a conversion premium of 32.5% to the last reported sale price of Mirion’s Class A common stock of $17.44 per share on May 20, 2025. The conversion rate is subject to adjustment under certain circumstances in accordance with the terms of the May Indenture. The Company may not redeem the 2030 Notes prior to June 6, 2028. The Company may redeem for cash 100% of the principal amount of the 2030 Notes being redeemed plus accrued and unpaid interest or any portion of the 2030 Notes, at its option, on or after June 6, 2028, but only if a certain liquidity condition has been satisfied and the last reported sale price of Mirion's Class A common stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period. If the Company redeems less than all of the outstanding 2030 Notes, at least $100.0 aggregate principal amount of the 2030 Notes must be outstanding and not subject to redemption as of, and after giving effect to, delivery of the relevant redemption notice. The 2030 Notes are convertible on or after March 1, 2030 until the close of business on the second scheduled trading day immediately preceding the maturity date, but can only be early exercised under the following circumstances: •During any calendar quarter after September 30, 2025 (and only during such calendar quarter) if the closing price of the Company's common stock for at least 20 trading days in a period of 30 consecutive trading days ending on and including the last trading day of the preceding calendar quarter is more than 130% of the then applicable conversion price for the 2030 Notes per share of common stock. •During the five business days immediately after any ten consecutive trading day period in which the trading price per $1,000 principal amount of 2030 Notes, as determined following a request by a holder of 2030 Notes, for each day of that period was less than 98% of the product of the closing price of our common stock and the then applicable conversion rate. •If the Company calls any or all of the 2030 Notes for redemption, holders may convert all or any portion of their 2030 Notes at any time prior to the close of business on the scheduled trading day prior to the redemption date, even if the 2030 Notes are not otherwise convertible at such time. •If specified distributions to holders of our common stock are made or specified corporate events occur. If the Company undergoes a fundamental change at any point, as defined in the May Indenture, then subject to certain conditions and limited exceptions, holders may require the Company to repurchase for cash all or any portion of their 2030 Notes in principal amounts of $1,000 or an integral multiple thereof at a repurchase price equal to 100% of the principal amount of the 2030 Notes to be repurchased plus accrued and unpaid interest. In addition, if specific corporate events occur prior to the maturity date or if the Company issues a notice of redemption, the Company will increase the conversion rate for holders who elect to convert their 2030 Notes in connection with such a corporate event. The conditions allowing holders of the 2030 Notes to convert were not met during the year ended December 31, 2025. Convertible Senior Notes due 2031 On September 30, 2025, concurrently with an offering of Mirion's Class A common stock, the Company completed a private offering of $375.0 million in aggregate principal amount of 0.00% Convertible Senior Notes due 2031, including the initial purchasers’ exercise in full of their option to purchase additional Notes (the “2031 Notes”). The Company used the net proceeds from these transactions to consummate a purchase of all of the outstanding membership interests of WCI-Gigawatt Intermediate Holdco, LLC, as the indirect parent of Paragon Energy Solutions, LLC, for $585.0 million pursuant to the equity purchase agreement signed September 24, 2025. The acquisition closed on December 2, 2025. Refer to Note 2, Business Combinations, Acquisitions, and Business Disposals, for additional information. The 2031 Notes were issued pursuant to an indenture, dated September 30, 2025 (the “September Indenture”). The September Indenture includes customary covenants and sets forth certain events of default after which the 2031 Notes may be declared immediately due and payable and sets forth certain types of bankruptcy or insolvency events of default involving the Company after which the outstanding principal and any unpaid special interest of the 2031 Notes becomes automatically due and payable. The 2031 Notes will mature on October 1, 2031, unless earlier converted, redeemed or repurchased. The 2031 Notes will not bear regular interest, and the principal amount of the 2031 Notes will not accrete. Special interest will accrue on the 2031 Notes in the circumstances at the rates set forth within the September Indenture. The 2031 Notes will be convertible at the option of the holders in certain circumstances discussed below. The 2031 Notes will be convertible into cash, shares of Mirion’s Class A common stock or a combination of cash and shares of Mirion’s Class A common stock, at the Company’s election. The initial conversion rate is 34.6951 shares of Mirion’s Class A common stock per $1,000 principal amount of 2031 Notes, which is equivalent to an initial conversion price of approximately $28.82 per share of Mirion's Class A common stock. The initial conversion price of the 2031 Notes represents a conversion premium of 35.0% to the related public offering price per share of Mirion Class A common stock of $21.35 per share. The conversion rate is subject to adjustment under certain circumstances in accordance with the terms of the September Indenture. The Company may not redeem the 2031 Notes prior to October 5, 2028. The Company may redeem for cash 100% of the principal amount of the 2031 Notes being redeemed plus any unpaid special interest or any portion of the 2031 Notes, at its option, on or after October 5, 2028, but only if a certain liquidity condition has been satisfied and the last reported sale price of Mirion's Class A common stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period. If the Company redeems less than all of the outstanding 2031 Notes, at least $100.0 million aggregate principal amount of the 2031 Notes must be outstanding and not subject to redemption as of, and after giving effect to, delivery of the relevant redemption notice. The 2031 Notes are convertible on or after July 1, 2031 until the close of business on the second scheduled trading day immediately preceding the maturity date, but can only be early exercised under the following circumstances: •During any calendar quarter after December 31, 2025 (and only during such calendar quarter) if the closing price of the Company's common stock for at least 20 trading days in a period of 30 consecutive trading days ending on and including the last trading day of the preceding calendar quarter is more than 130% of the then applicable conversion price for the 2031 Notes per share of common stock. •During the five business days immediately after any ten consecutive trading day period in which the trading price per $1,000 principal amount of 2031 Notes, as determined following a request by a holder of 2031 Notes, for each day of that period was less than 98% of the product of the closing price of our common stock and the then applicable conversion rate. •If the Company calls any or all of the 2031 Notes for redemption, holders may convert all or any portion of their 2031 Notes at any time prior to the close of business on the scheduled trading day prior to the redemption date, even if the 2031 Notes are not otherwise convertible at such time. •If specified distributions to holders of our common stock are made or specified corporate events occur. If the Company undergoes a fundamental change at any point, as defined in the September Indenture, then subject to certain conditions and limited exceptions, holders may require the Company to repurchase for cash all or any portion of their 2031 Notes in principal amounts of $1,000 or an integral multiple thereof at a repurchase price equal to 100% of the principal amount of the 2031 Notes to be repurchased plus any unpaid special interest. In addition, if specific corporate events occur prior to the maturity date or if the Company issues a notice of redemption, the Company will increase the conversion rate for holders who elect to convert their 2031 Notes in connection with such a corporate event. The conditions allowing holders of the 2031 Notes to convert were not met during the year ended December 31, 2025. Interest and Maturity As of December 31, 2025, the 2030 Notes and 2031 Notes are classified as long-term liabilities, net of issuance costs of $12.4 million and $9.9 million, respectively, on the Consolidated Balance Sheets. As of December 31, 2025, the net carrying amount of the 2030 Notes and 2031 Notes approximates fair value. As the 2030 Notes and 2031 Notes were not issued at a premium, no portion of the proceeds from the issuance of the 2030 Notes and 2031 Notes met the requirements to be accounted for separately as a component of stockholders’ equity. The 2030 Notes and 2031 Notes were issued at par, and costs associated with the issuance of the 2030 Notes and 2031 Notes are amortized to interest expense over the contractual term of the respective Notes. Interest expense (including amortization of deferred issuance costs) recognized related to the 2030 Notes and the 2031 Notes for the year ended December 31, 2025 was $2.2 million and $0.4 million, respectively. No special interest was recorded for the 2031 Notes during the year ended December 31, 2025. As of December 31, 2025, the effective interest rate of the 2030 Notes is 0.88%. At December 31, 2025, future maturities of the 2030 and 2031 Notes are as follows (in millions):
Fiscal year ending December 31: |
2026 | $ | — |
2027 | — |
2028 | — |
2029 | — |
2030 | 400.0 |
Thereafter | 375.0 |
| $ | 775.0 |
Capped Call Transactions In May 2025, subsequent to the pricing of the 2030 Notes, the Company entered into privately negotiated capped call transactions (the “May Capped Call Transactions”). The May Capped Call Transactions initially cover, subject to customary anti-dilution adjustments substantially similar to those applicable to the 2030 Notes, the number of shares of Mirion’s Class A common stock that underlie the 2030 Notes for the purpose of limiting the potentially dilutive impacts of the 2030 Notes. The cap price of the May Capped Call Transactions is initially $34.88 per share, which represents a premium of 100% over the last reported sale price of Mirion’s Class A common stock of $17.44 per share on May 20, 2025, and is subject to certain adjustments under the terms of the May Capped Call Transactions. The initial strike price of the May Capped Call Transactions is equal to the initial conversion price of the 2030 Notes. The default settlement method is net share settlement; however, the Company may elect to settle the May Capped Call Transactions in cash. The Company used $44.6 million of the proceeds from the offering of 2030 Notes to pay the cost of the May Capped Call Transactions. In September 2025, in connection with the pricing of the 2031 Notes, the Company entered into privately negotiated capped call transactions (the "September Capped Call Transactions"). The September Capped Call Transactions initially cover, subject to customary anti-dilution adjustments substantially similar to those applicable to the 2031 Notes, the number of shares of Mirion's Class A common stock that underlie the 2031 Notes for the purpose of limiting the potentially dilutive impacts of the 2031 Notes. The cap price of the September Capped Call Transactions is initially $42.70 per share, which represents a premium of 100% over the related public offering price per share of Mirion Class A common stock of $21.35, and is subject to certain adjustments under the terms of the September Capped Call Transactions. The initial strike price of the September Capped Call Transactions is equal to the initial conversion price of the 2031 Notes. The default settlement method is net share settlement; however, the Company may elect to settle the September Capped Call Transactions in cash. The Company used $38.0 million of the proceeds from the offering of the 2031 Notes to pay the cost of the September Capped Call Transactions. The Company evaluated the May and September Capped Call Transactions and determined that they should be accounted as separate transactions from the 2030 Notes and 2031 Notes, respectively. The costs of $44.6 million to purchase the May Capped Call Transactions and $38.0 million to purchase the September Capped Call Transactions were recorded as a reduction to additional paid-in capital in the Consolidated Balance Sheets as of December 31, 2025, since they are indexed to the Company’s stock and met the criteria to be classified in stockholders' equity in accordance with ASC 815-40, Contracts in Entity's Own Equity. Share Repurchases Concurrently with the pricing of the 2030 Notes, the Company entered into privately negotiated transactions to use $31.0 million of the net proceeds from the offering of the 2030 Notes to repurchase shares of Mirion’s Class A common stock. The Company repurchased shares of Class A common stock sold short by investors in the offering of the 2030 Notes at a purchase price per share equal to the last reported sale price of Mirion’s Class A common stock of $17.44 per share on May 20, 2025. Such repurchases of shares of Mirion’s Class A common stock are separate from, and in addition to, repurchases under the Company’s existing stock repurchase program.

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- Definition The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8A -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A Reference 2: http://www.xbrl.org/2003/role/disclosureRef 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