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v3.25.3

Defined benefit pension plans | 9 Months Ended
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Sep. 30, 2025
Defined benefit pension plans |
Defined benefit pension plans | Note 11 – Defined benefit pension plans: NL administers a U.S. pension plan which has been closed to new participants since 1996. In accordance with applicable U.S. pension regulations, effective June 30, 2025 NL began the process of terminating the pension plan, which includes the purchase of annuity contracts from a third-party insurance company for the purpose of distributing benefits to plan participants. The termination process involves several steps and is expected to take between six and twelve months to complete. Following the purchase of the annuity contracts for plan participants, we will remove pension plan assets and liabilities from our Condensed Consolidated Financial Statements and a plan settlement gain or loss (which we are currently unable to estimate) will be included in our net periodic pension cost. The plan termination is expected to be completed with existing plan funds. At December 31, 2024 the U.S. pension plan had a benefit obligation of $65.2 million, plan assets of $75.7 million and a pension plan asset of $10.7 million. ​ ​ ​ ​ The components of our net periodic defined benefit pension cost are presented in the table below. ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three months ended | ​ | Nine months ended
​ | ​ | September 30, | ​ | September 30,
​ |  | 2024 |  | 2025 |  | 2024 |  | 2025
​ | ​ | (In millions)
Service cost | ​ | $ | 1.6 | ​ | $ | 1.5 | ​ | $ | 4.9 | ​ | $ | 4.4
Interest cost | ​ | ​ | 5.3 | ​ | ​ | 6.0 | ​ | ​ | 15.9 | ​ | ​ | 17.3
Expected return on plan assets | ​ |  | (5.5) | ​ |  | (6.1) | ​ |  | (16.7) | ​ |  | (17.5)
Recognized net actuarial losses | ​ |  | 1.0 | ​ |  | .8 | ​ |  | 2.9 | ​ |  | 2.4
Total | ​ | $ | 2.4 | ​ | $ | 2.2 | ​ | $ | 7.0 | ​ | $ | 6.6
​ We expect to contribute the equivalent of approximately $16 million to all of our defined benefit pension plans during 2025.

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