White Mountains accounts for business combinations using the acquisition method. Under the acquisition method, White Mountains recognizes and measures the assets acquired, including other intangible assets, and liabilities assumed, including contingent consideration liabilities, at their estimated fair values as of the acquisition date. Goodwill represents the excess of the amount paid to acquire a business over the fair value of identifiable net assets at the acquisition date. The estimated acquisition date fair values, generally consisting of intangible assets and contingent consideration liabilities, may be recorded at provisional amounts in circumstances where the information necessary to complete the acquisition accounting is not available at the reporting date. Any such provisional amounts are finalized as measurement period adjustments within one year of the acquisition date.

The following tables present the economic life, acquisition date fair value, accumulated amortization and net carrying value for goodwill and other intangible assets as of March 31, 2026 and December 31, 2025:


$ in Millions	Weighted Average Economic Life (in years)	March 31, 2026
		Acquisition Date Fair Value		Accumulated Amortization		Impairments (1)		Net Carrying Value
Goodwill:
Ark	N/A	$	116.8	$	—	$	—	$	116.8
Kudu	N/A	7.6		—		—		7.6
Distinguished (2)	N/A	397.9		—		—		397.9
Other Operations	N/A	102.1		—		9.1		93.0
Total goodwill		624.4		—		9.1		615.3
Other intangible assets:
Ark
Underwriting capacity	N/A	175.7		—		—		175.7








Kudu
Trade names	7.0	2.2		2.2		—		—
Distinguished (2)
Trade names	10.0	24.3		1.4		—		22.9
Agency relationships	8.0	127.9		9.5		—		118.4
Developed technology	5.0	36.6		4.3		—		32.3
Subtotal		188.8		15.2		—		173.6
Other Operations
Trade names	11.7	22.4		8.1		.2		14.1
Customer relationships	8.8	53.3		21.1		.3		31.9


Other	11.7	3.1		2.0		—		1.1
Subtotal		78.8		31.2		.5		47.1
Total other intangible assets		445.5		48.6		.5		396.4
Total goodwill and other intangible assets		$	1,069.9	$	48.6	$	9.6	$	1,011.7

(2) The relative fair values of goodwill and other intangible assets recognized in connection with the Distinguished Transaction had not yet been finalized. See Note 2 — “Significant Transactions.”


$ in Millions	Weighted Average Economic Life (in years)	December 31, 2025
		Acquisition Date Fair Value		Accumulated Amortization		Impairments (1)		Net Carrying Value
Goodwill:
Ark	N/A	$	116.8	$	—	$	—	$	116.8
Kudu	N/A	7.6		—		—		7.6
Distinguished (2)	N/A	396.7		—		—		396.7
Other Operations (2)	N/A	102.1		—		9.1		93.0
Total goodwill		623.2		—		9.1		614.1
Other intangible assets:
Ark
Underwriting capacity	N/A	175.7		—		—		175.7








Kudu
Trade names	7.0	2.2		2.1		—		.1
Distinguished (2)
Trade names	10.0	24.3		.8		—		23.5
Agency relationships	8.0	127.9		5.0		—		122.9
Developed technology	5.0	36.6		2.0		—		34.6
Subtotal		188.8		7.8		—		181.0
Other Operations (2)
Trade names	11.7	22.4		7.7		.2		14.5
Customer relationships	8.8	53.3		19.4		.3		33.6


Other	11.8	3.1		1.9		—		1.2
Subtotal		78.8		29.0		.5		49.3
Total other intangible assets		445.5		38.9		.5		406.1
Total goodwill and other intangible assets		$	1,068.7	$	38.9	$	9.6	$	1,020.2

(2) The relative fair values of goodwill and other intangible assets recognized in connection with the Distinguished Transaction and the Enterprise Solutions Transaction had not yet been finalized. See Note 2 — “Significant Transactions.”


	Three Months Ended March 31,
	2026						2025
Millions	Goodwill		Other Intangible Assets		Total Goodwill and Other Intangible Assets		Goodwill		Other Intangible Assets		Total Goodwill and Other Intangible Assets
Beginning balance	$	614.1	$	406.1	$	1,020.2	$	439.2	$	281.1	$	720.3



Measurement period adjustments (1)	1.2		—		1.2		—		—		—

Amortization	—		(9.7)		(9.7)		—		(5.2)		(5.2)


Ending balance	$	615.3	$	396.4	$	1,011.7	$	439.2	$	275.9	$	715.1

(1) Measurement period adjustments relate to updated information about acquisition date fair values of assets acquired and liabilities assumed. Adjustments relate to the Distinguished Transaction.