(4) Goodwill and Intangible Assets

Intangible Assets Subject to Amortization, net

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Intangible assets are being amortized generally on an accelerated basis as reflected in amortization expense and in the future amortization table below.

Amortization expense for intangible assets with finite useful lives was  $15 million and $15 million for the three months ended June 30, 2025 and 2024, respectively, and $29 million and $30 million for the six months ended June 30, 2025 and 2024, respectively. Amortization expense for amortizable intangible assets for each of the five succeeding fiscal years is estimated to be (amounts in millions):

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