Page 131 - Martin Marietta - 2023 Proxy Statement

NOTES TO FINANCIAL STATEMENTS (Continued)

Intangible assets subject to amortization consist of the following:
Gross Accumulated Net
December 31 Amount Amortization Balance
(in millions) 2022
Noncompetition agreements $ 4.1 $ (4.0) $ 0.1
Customer relationships 423.7 (62.7) 361.0
Operating permits 502.2 (61.4) 440.8
Use rights and other 13.9 (12.4) 1.5
Trade names 23.3 (14.7) 8.6
Total $ 967.2 $ (155.2) $ 812.0

2021
Noncompetition agreements $ 4.2 $ (4.1) $ 0.1
Customer relationships 425.3 (49.2) 376.1
Operating permits 697.3 (56.6) 640.7
Use rights and other 16.3 (13.9) 2.4
Trade names 23.3 (13.6) 9.7
Total $ 1,166.4 $ (137.4) $ 1,029.0

Intangible assets subject to amortization decreased in 2022 due to measurement period adjustments to acquisition‐date fair values
and the divestiture of the Company's Colorado and Central Texas ready mixed concrete businesses (see Note C).

Intangible assets deemed to have an indefinite life that are therefore not amortized consist of the following:
Building
Materials Magnesia
December 31 Business Specialties Total
(in millions) 2022
Operating permits $ 6.6 $ — $ 6.6
Use rights 26.7 — 26.7
Trade names — 2.5 2.5
Total $ 33.3 $ 2.5 $ 35.8

2021
Operating permits $ 6.6 $ — $ 6.6
Use rights 26.7 — 26.7
Trade names 0.2 2.5 2.7
Total $ 33.5 $ 2.5 $ 36.0

Total amortization expense for intangible assets for the years ended December 31, 2022, 2021 and 2020 was $26.6 million, $24.0
million and $13.4 million, respectively. The intangible assets classified as held for sale are not being amortized.
The estimated amortization expense for intangible assets for each of the next five years and thereaftf er is as follows:
(in millions)
2023 $ 28.1
2024 28.0
2025 27.9
2026 26.6
2027 25.8
Thereafter 675.6
Total $ 812.0

Annual Report ♦ Page 27