Intangible Assets

3 Months Ended

Mar. 31, 2022

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

6.   Intangible Assets

The gross book value, accumulated amortization and net book value of intangible assets were as follows:

	(Stated in millions)
	Mar. 31, 2022						Dec. 31, 2021
	Gross		Accumulated		Net Book		Gross		Accumulated		Net Book
	Book Value		Amortization		Value		Book Value		Amortization		Value
Customer relationships	$	1,676	$	567	$	1,109	$	1,681	$	551	$	1,130
Technology/technical know-how		1,265		587		678		1,264		562		702
Tradenames		766		199		567		766		191		575
Other		1,549		745		804		1,529		725		804
	$	5,256	$	2,098	$	3,158	$	5,240	$	2,029	$	3,211

Amortization expense charged to income was $75 million during the first quarter of 2022 and $76 million during the first quarter of 2021.

Based on the net book value of intangible assets at March 31, 2022, amortization expense for the subsequent five years is estimated to be: remaining three quarters of 2022—$227 million; 2023—$291 million; 2024—$279 million; 2025—$261 million; 2026—$256 million; and 2027—$252 million.