Goodwill — Goodwill represents the excess of the purchase price over the identifiable tangible and intangible assets acquired plus liabilities assumed arising from business combinations. The balance of goodwill was $1.9 million as of December 31, 2024 and 2023, as a result of the Company's acquisition of V-Go in May 2022. Goodwill is tested at least annually for impairment by assessing qualitative factors in determining whether it is more likely than not that the fair value of net assets is below their carrying amounts. See Note 2 – Summary of Significant Accounting Policies.

Other Intangible Assets — Other intangible assets consisted of the following (in thousands):


	Estimated		December 31, 2024							December 31, 2023
	Useful Life (Years)		Cost		Accumulated Amortization			Net Book Value		Cost		Accumulated Amortization			Net Book Value
Developed technology		7.5	$	1,200	$	(235	)	$	965	$	1,200	$	(127	)	$	1,073
iSPERSE License – IPR&D		—		4,300		—			4,300		—		—			—
Total			$	5,500	$	(235	)	$	5,265	$	1,200	$	(127	)	$	1,073

Amortization expense related to the developed technology was $0.1 million and $0.1 million for the years ended December 31, 2024 and 2023, respectively. The estimated annual amortization expense for the developed technology will be approximately $0.2 million per year for the years ended December 31, 2025 through 2029.

The iSPERSE License – IPR&D is an indefinite-lived intangible asset, and as such is not amortized but rather is tested for impairment when facts or circumstances indicate the carrying value of the asset may not be recoverable. Upon completion of the underlying R&D efforts, the intangible asset will be accounted for as a finite-lived intangible asset. If the R&D efforts are abandoned, the IPR&D asset balance will be written off to R&D expense. The iSPERSE License – IPR&D was acquired from Pulmatrix in July 2024. See Note 3 – Pulmatrix Transaction.

The Company evaluates its other intangible assets for potential impairment when events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. See Note 2 – Summary of Significant Accounting Policies.