The following table provides the gross carrying value, accumulated amortization, net book value and remaining useful life for intangible assets subject to amortization as of September 30, 2024:


	Gross Carrying Value		Accumulated Amortization		Net Book Value		Weighted Average Remaining Useful Life (Years)
Accreditations and regulatory approvals	$	16,300	$	—	$	16,300	Indefinite
Trademarks, trade names and other	1,942		(1,066)		876		4.33
Curriculum	1,800		(747)		1,053		3.00

Total	$	20,042	$	(1,813)	$	18,229	3.60

The following table provides the gross carrying value, accumulated amortization, net book value and remaining useful life for those intangible assets that were subject to amortization as of September 30, 2023:


	Gross Carrying Value		Accumulated Amortization		Net Book Value		Weighted Average Remaining Useful Life (Years)
Accreditations and regulatory approvals	$	16,300	$	—	$	16,300	Indefinite
Trademarks, trade names and other	1,942		(680)		1,262		5.17
Curriculum	1,800		(387)		1,413		3.98

Total	$	20,042	$	(1,067)	$	18,975	4.54

Amortization expense for the year ended September 30, 2024, 2023, and 2022 was $0.7 million, $0.6 million, and $0.1 million, respectively.

Intangible assets subject to amortization as of September 30, 2024, will be amortized as follows:


	2025		2026		2027		2028		2029		Thereafter
Estimated future amortization expense	$	877	$	410	$	337	$	97	$	50	$	158

Of the $18.2 million net book value recorded as intangible assets as of September 30, 2024, $4.8 million relates to the Concorde asset group and $13.4 million relates to the UTI asset group. The weighted average remaining useful lives are calculated based on the net book value and the remaining amortization period of each respective intangible asset.