22.

COMMITMENTS

The Company’s commitments as of December 31, 2017 were as follows:


In millions of U.S. dollars	Total		2018		2019		2020		2021		2022		Thereafter
Operating leases		227		55		40		32		21		13		66
Purchase obligations		1,423		946		232		129		116		—		—
of which:
Equipment purchase		774		684		90		—		—		—		—
Foundry purchase		557		198		123		120		116		—		—
Software, design, technologies and licenses		92		64		19		9		—		—		—
Other obligations		324		161		98		41		15		6		3

Total		1,974		1,162		370		202		152		19		69

Operating leases are mainly related to building and equipment leases. The amount disclosed is composed of minimum payments for future leases from 2018 to 2022 and thereafter. The Company leases land, buildings, plants and equipment under operating leases that expire at various dates under non-cancellable lease agreements. Operating lease expense was $67 million for the year ended December 31, 2017 and $56 million for the years ended December 31, 2016 and 2015.

Purchase obligations are primarily comprised of purchase commitments for equipment, for outsourced foundry wafers and for software licenses.

Other obligations primarily relate to firm contractual commitments with respect to partnership and cooperation agreements and other service agreements.