SUPPLEMENTAL BALANCE SHEET INFORMATION

Components of selected captions in our accompanying unaudited condensed consolidated balance sheets are as follows:

Trade accounts receivable, net



	As of
(in millions)	March 31, 2013			December 31, 2012
Accounts receivable	$	1,346		$	1,336
Less: allowance for doubtful accounts	(86		)	(88		)
Less: allowance for sales returns	(28		)	(31		)
	$	1,232		$	1,217

The following is a rollforward of our allowance for doubtful accounts for the first quarter of 2013 and 2012:



	Three Months Ended March 31,
(in millions)	2013			2012
Beginning balance	$	88		$	81
Charges to expenses	3			9
Utilization of allowances	(5		)
Ending balance	$	86		$	90

Inventories



	As of
(in millions)	March 31, 2013		December 31, 2012
Finished goods	$	583	$	598
Work-in-process	78		70
Raw materials	190		216
	$	851	$	884

Property, plant and equipment, net



	As of
(in millions)	March 31, 2013		December 31, 2012
Land	$	81	$	81
Buildings and improvements	895		873
Equipment, furniture and fixtures	2,346		2,348
Capital in progress	195		218
	3,517		3,520
Less: accumulated depreciation	1,980		1,956
	$	1,537	$	1,564

Depreciation expense was $61 million for the first quarter of 2013 and $66 million for the first quarter of 2012.

Accrued expenses



	As of
(in millions)	March 31, 2013		December 31, 2012
Payroll and related liabilities	$	356	$	452
Accrued contingent consideration	132		120
Legal reserves	127		100
Other	571		612
	$	1,186	$	1,284

Other long-term liabilities



	As of
(in millions)	March 31, 2013		December 31, 2012
Accrued income taxes	$	1,243	$	1,215
Accrued contingent consideration	510		543
Legal reserves	521		391
Other long-term liabilities	390		398
	$	2,664	$	2,547

Accrued warranties

We offer warranties on certain of our product offerings. The majority of our warranty liability as of March 31, 2013 related to implantable devices offered by our CRM business, which include defibrillator and pacemaker systems. Our CRM products come with a standard limited warranty covering the replacement of these devices. We offer a full warranty for a portion of the period post-implant, and a partial warranty over the substantial remainder of the useful life of the product. We estimate the costs that we may incur under our warranty programs based on the number of units sold, historical and anticipated rates of warranty claims and cost per claim, and record a liability equal to these estimated costs as cost of products sold at the time the product sale occurs. We reassess the adequacy of our recorded warranty liabilities on a quarterly basis and adjust these amounts as necessary. The current portion of our warranty accrual is included in other accrued expenses in the table above and the non-current portion of our warranty accrual is included in other long-term liabilities in the table above. Changes in our product warranty accrual during the first three months of 2013 and 2012 consisted of the following (in millions):



	Three Months Ended March 31,
	2013			2012
Beginning Balance	$	26		$	30
Provision	4
Settlements/reversals	(3		)	(7		)
Ending Balance	$	27		$	23