Earnings (Loss) Per Share Calculation

9 Months Ended

Jul. 31, 2011

Earnings (Loss) Per Share Calculation [Abstract]

EARNINGS (LOSS) PER SHARE CALCULATION

(15) 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.

	Quarter Ended July 31,						Nine Months Ended July 31,
Numerator	2010			2011			2010			2011
Net loss	$	(109,855	)	$	(31,450	)	$	(253,197	)	$	(173,192	)

	Quarter Ended July 31,				Nine Months Ended July 31,
Denominator	2010		2011		2010		2011
Basic weighted average shares outstanding		92,906		96,313		92,851		95,389
Dilutive weighted average shares outstanding		92,906		96,313		92,851		95,389

	Quarter Ended July 31,						Nine Months Ended July 31,
EPS	2010			2011			2010			2011
Basic EPS	$	(1.18	)	$	(0.33	)	$	(2.73	)	$	(1.82	)
Diluted EPS	$	(1.18	)	$	(0.33	)	$	(2.73	)	$	(1.82	)

     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):

	Quarter Ended July 31,				Nine Months Ended July 31,
	2010		2011		2010		2011
Shares underlying stock options, restricted stock units and warrants		7,171		6,032		8,171		6,295
0.25% Convertible Senior Notes due May 1, 2013		7,539		5,470		7,539		5,470
4.00% Convertible Senior Notes due March 15, 2015		18,396		18,396		9,333		18,396
0.875% Convertible Senior Notes due June 15, 2017		13,108		13,108		13,108		13,108
3.75% Convertible Senior Notes due October 15, 2018		—		17,355		—		17,355
Total excluded due to anti-dilutive effect		46,214		60,361		38,151		60,624