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Exhibit 12.1

Tyco International Ltd.

Computation of Ratio of Earnings to Fixed Charges⁽¹⁾ (unaudited)

(dollars in millions)

	For The Six Months Ended
						Fiscal
	March 26, 2010		March 27, 2009
						2009			2008		2007			2006		2005
Earnings:
Income (loss) from continuing operations before income taxes		719		(2,258	)		(1,751	)		1,431		(2,196	)		1,122		596
Add: Fixed Charges		212		215			433			535		451			409		456
Less: Capitalized interest		1		1			1			1		3			1		1
		930		(2,044	)		(1,319	)		1,965		(1,748	)		1,530		1,051
Fixed Charges:
Interest expense before capitalized interest		150		151			301			396		313			279		322
Capitalized interest		1		1			1			1		3			1		1
Rentals (one-third rent)		61		63			131			138		135			129		133
Total fixed charges		212		215			433			535		451			409		456
Ratio of earnings to fixed charges		4.39		—	(2)		—	(3)		3.67		—	(4)		3.74		2.30

⁽¹⁾

The ratio of earnings to fixed charges is computed by dividing the sum of earnings before income taxes and fixed charges by fixed charges. Fixed charges represent interest expense (before interest is capitalized), amortization of debt premiums and discounts, capitalized expenses related to indebtedness and an appropriate interest factor on operating leases. Fixed charges represent amounts relating to continuing operations.

⁽²⁾

For the six months ended March 27, 2009, fixed charges exceeded earnings by $2,259 million.

⁽³⁾

In fiscal 2009, fixed charges exceeded earnings by $1,752 million.

⁽⁴⁾

In fiscal 2007, fixed charges exceeded earnings by $2,199 million.

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Exhibit 12.1

Tyco International Ltd. Computation of Ratio of Earnings to Fixed Charges⁽¹⁾ (unaudited) (dollars in millions)