Net Income Per Share (Tables)

6 Months Ended

Jun. 28, 2019

Earnings Per Share [Abstract]

Basic and Diluted Net Income (loss) Per Share

The following is a reconciliation of the numerators and denominators used in computing basic and diluted net income (loss) per share (in thousands, except per share data):

	Three Months Ended					Six Months Ended
	June 28,			June 29,		June 28,		June 29,
	2019			2018		2019		2018
Numerator:
Net income (loss) attributable to Ultra Clean    Holdings, Inc.	$	(202	)	$	18,960	$	403	$	43,701
Denominator:
Shares used in computation — basic:
Weighted average common shares    outstanding		39,399			38,802		39,261		37,763
Shares used in computation — diluted:
Shares used in computing basic net    income per share		39,399			38,802		39,261		37,763
Dilutive effect of common shares    outstanding subject to repurchase		—			489		294		649
Dilutive effect of options outstanding		—			6		1		6
Weighted average shares used in    computing diluted net income (loss) per share		39,399			39,297		39,556		38,418
Net income (loss) per share attributable    to Ultra Clean Holdings, Inc. — basic	$	(0.01	)	$	0.49	$	0.01	$	1.16
Net income (loss) per share attributable    to Ultra Clean Holdings, Inc. — diluted	$	(0.01	)	$	0.48	$	0.01	$	1.14