Intangible assets

12 Months Ended

Mar. 31, 2016

Intangible assets

Intangible assets

16.   Intangible assets

	As of March 31,
	2015			2016
	(in millions of RMB)
Non-compete agreements		3,630			4,284
Developed technology and patents		3,331			3,652
Trade names, trademarks and domain names		2,007			2,222
User base and customer relationships		855			1,234
Licenses and copyrights and others		295			787
Less: accumulated amortization and impairment		(3,543	)		(6,809	)
Net book value		6,575			5,370

Amortization expenses for the years ended March 31, 2014, 2015 and 2016 amounted to RMB315 million, RMB2,089 million and RMB2,931 million, respectively. During the same periods, no impairment charge was recognized in the consolidated income statements.

The estimated aggregate amortization expenses for each of the five succeeding fiscal years and thereafter are as follows:

	Amounts
	(in millions of RMB)
For the year ending March 31,
2017		3,103
2018		1,734
2019		449
2020		71
2021		8
Thereafter		5
		5,370