Intangible assets subject to amortization include patents and a license agreement capitalized as part of the Novartis RNAi asset acquisition in March 2015. The following table presents the components of intangible assets:


	Gross Carrying Amount		Accumulated Amortization		Impairment		Net Carrying Amount		Useful Lives
	(in thousands)								(in years)
As of June 30, 2026
Patents	$	21,728	$	17,589	$	—	$	4,139	14
License	3,129		1,682		—		1,447		21
Total intangible assets, net	$	24,857	$	19,271	$	—	$	5,586
As of
As of September 30, 2025
Patents	$	21,728	$	16,426	$	—	$	5,302	14
License	3,129		1,570		—		1,559		21
Total intangible assets, net	$	24,857	$	17,996	$	—	$	6,861

Intangible assets are reviewed annually for impairment and more frequently if potential impairment indicators exist. No impairment indicators were identified during the nine months ended June 30, 2026 and 2025.

Intangible assets with definite useful lives are amortized on a straight-line basis over their useful lives. Intangible assets amortization expense was $0.4 million for the three months ended June 30, 2026 and 2025, and $1.3 million for each of the nine months ended June 30, 2026 and 2025. None of the intangible assets with definite useful lives are anticipated to have a residual value.

The following table presents the estimated future amortization expense related to intangible assets as of June 30, 2026:


	Amortization Expense
Year Ending September 30,	(in thousands)
2026 (remainder)	$	425
2027	1,700
2028	1,700
2029	795
2030	149
Thereafter	817
Total	$	5,586