Acquired Intangible Assets

The Company’s acquired intangible assets with definite useful lives primarily consist of patents and licenses. The following table summarizes the components of gross and net acquired intangible asset balances as of September 24, 2016 and September 26, 2015 (in millions):



	2016							2015
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Definite-lived and amortizable acquired intangible assets	$	8,912	$	(5,806	)	$	3,106	$	8,125	$	(4,332	)	$	3,793
Indefinite-lived and non-amortizable acquired intangible assets	100		—			100		100		—			100
Total acquired intangible assets	$	9,012	$	(5,806	)	$	3,206	$	8,225	$	(4,332	)	$	3,893

Amortization expense related to acquired intangible assets was $1.5 billion, $1.3 billion and $1.1 billion in 2016, 2015 and 2014, respectively. As of September 24, 2016, the remaining weighted-average amortization period for acquired intangible assets is 3.4 years. The expected annual amortization expense related to acquired intangible assets as of September 24, 2016, is as follows (in millions):



2017	$	1,197
2018	902
2019	449
2020	255
2021	175
Thereafter	128
Total	$	3,106