Earnings (Loss) Per Share Calculation

12 Months Ended

Oct. 31, 2011

Earnings Per Share [Abstract]

EARNINGS (LOSS) PER SHARE CALCULATION

EARNINGS (LOSS) PER SHARE CALCULATION

The following table (in thousands except per share amounts) is a reconciliation of the numerator and denominator of the basic net income (loss) per common share (“Basic EPS”) and the diluted net income (loss) per potential common share (“Diluted EPS”). Basic EPS is computed using the weighted average number of common shares outstanding. Diluted EPS is computed using the weighted average number of (i) common shares outstanding, (ii) shares issuable upon vesting of restricted stock units, (iii) shares issuable under Ciena's employee stock purchase plan and upon exercise of outstanding stock options, using the treasury stock method; and (iv) shares underlying Ciena's outstanding convertible notes.

Numerator

	Year Ended October 31,
	2009			2010			2011
Net loss	$	(581,154	)	$	(333,514	)	$	(195,521	)

Denominator

	Year Ended October 31,
	2009	2010	2011
Basic weighted average shares outstanding	91,167	93,103	95,854
Dilutive weighted average shares outstanding	91,167	93,103	95,854

EPS

	Year Ended October 31,
	2009			2010			2011
Basic EPS	$	(6.37	)	$	(3.58	)	$	(2.04	)
Diluted EPS	$	(6.37	)	$	(3.58	)	$	(2.04	)

The following table summarizes the weighted average shares excluded from the calculation of the denominator for Basic and Diluted EPS due to their anti-dilutive effect for the fiscal years indicated (in thousands):

	Year Ended October 31,
	2009	2010	2011
Shares underlying stock options, restricted stock units and warrants	8,302	7,397	6,141
0.25% Convertible Senior Notes due May 1, 2013	7,539	7,454	5,470
4.00% Convertible Senior Notes due March 15, 2015	—	11,605	18,395
0.875% Convertible Senior Notes due June 15, 2017	13,108	13,108	13,108
3.75% Convertible Senior Notes due October 15, 2018	—	717	17,356
Total excluded due to anti-dilutive effect	28,949	40,281	60,470