Intangible Assets

6 Months Ended

Mar. 31, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

The gross and net carrying values of intangible assets as of the balance sheet dates, by major intangible asset class are as follows (in millions):


	March 31, 2024						September 30, 2023
	Gross Amount		Accumulated Amortization		Net Amount		Gross Amount		Accumulated Amortization		Net Amount
Intangible assets subject to amortization
Trade/domain names	$	4.1	$	(2.8)	$	1.3	$	4.1	$	(2.4)	$	1.7
Software programs/platforms	4.9		(3.7)		1.2		28.5		(26.9)		1.6
Client and supplier base	35.2		(23.0)		12.2		38.3		(24.1)		14.2
Total intangible assets subject to amortization	44.2		(29.5)		14.7		70.9		(53.4)		17.5

Intangible assets not subject to amortization
Website domains	2.0		—		2.0		1.9		—		1.9
Business licenses	3.7		—		3.7		3.7		—		3.7
Total intangible assets not subject to amortization	5.7		—		5.7		5.6		—		5.6
Total intangible assets	$	49.9	$	(29.5)	$	20.4	$	76.5	$	(53.4)	$	23.1

Amortization expense related to intangible assets was $2.1 million and $4.1 million for the three months ended March 31, 2024 and 2023, respectively. Amortization expense related to intangible assets was $4.1 million and $8.0 million for the six months ended March 31, 2024 and 2023, respectively.

The Company wrote off $27.8 million of fully amortized intangible assets during the six months ended March 31, 2024.

As of March 31, 2024, estimated future amortization expense was as follows:


(in millions)
Fiscal 2024 (remaining months)	$	3.0
Fiscal 2025	3.7
Fiscal 2026	2.9
Fiscal 2027	2.3
Fiscal 2028 and thereafter	2.8
Total intangible assets subject to amortization	$	14.7