EXHIBIT 11

TELLABS, INC.

COMPUTATION OF PER SHARE EARNINGS

In millions, except per share amounts

	Third Quarter					Nine Months
	9/26/08			9/28/07		9/26/08			9/28/07
Numerator:
Net (loss) earnings	$	(998.5	)	$	3.6	$	(942.9	)	$	58.7
Denominator:
Denominator for basic earnings per share -
Weighted average shares outstanding		398.0			439.2		401.1			438.5
Effect of dilutive securities:
Stock options and awards		—			5.3		—			5.3
Denominator for diluted earnings per share -
Adjusted weighted average shares outstanding and assumed conversions		398.0			444.5		401.1			443.8
Net (loss) earnings per share – basic	$	(2.51	)	$	0.01	$	(2.35	)	$	0.13
Net (loss) earnings per share – diluted	$	(2.51	)	$	0.01	$	(2.35	)	$	0.13

Under GAAP, dilutive securities are not included in the computation of diluted earnings per share when a company is in a loss position.

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