(5) Intangible Assets

Intangible Assets Subject to Amortization, net

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Amortization expense for intangible assets with finite useful lives was $16 million and $17 million for the three months ended September 30, 2023 and 2022, respectively, and $48 million and $50 million for the nine months ended September 30, 2023 and 2022, 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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