Acacia’s only identifiable intangible assets are patents and patent rights, with estimated remaining economic useful lives ranging from one to nine years. For all periods presented, all of Acacia’s identifiable intangible assets were subject to amortization. The gross carrying amounts and accumulated amortization related to acquired intangible assets as of December 31, 2012 and 2011 are as follows (in thousands):



	2012			2011

Gross carrying amount - patents	$	383,379		$	61,519
Accumulated amortization - patents	(69,850		)	(36,331		)
Patents, net	$	313,529		$	25,188

The weighted-average remaining estimated economic useful life of Acacia’s patents and patent rights is 7 years. Scheduled annual aggregate amortization expense for each of the next five years through December 31, 2017 is estimated to be $45,144,000 in 2013, $44,864,000 in 2014, $44,387,000 in 2015, $43,560,000 in 2016, and $39,644,000 in 2017.

For the years ended December 31, 2012, 2011 and 2010, on a consolidated basis, Acacia’s operating subsidiaries incurred and capitalized patent and patent rights acquisition costs totaling $178,260,000 (excluding the acquisition of ADAPTIX), $14,680,000 and $8,224,000, respectively. The patents have estimated economic useful lives ranging from one to eight years. Included in capitalized patent costs as of December 31, 2012 and 2011 are $0 and $900,000, respectively, of accrued future patent-related acquisition costs that management expects to incur pursuant to the terms of the underlying patent acquisition agreements, which are being amortized over the estimated economic useful life of the patents acquired.

Refer to Note 8 to these consolidated financial statements for additions to patents and goodwill in connection with Acacia’s acquisition of ADAPTIX and the related application of the acquisition method of accounting.

During the periods presented, certain operating subsidiaries recovered up-front patent portfolio acquisition costs from applicable net licensing proceeds prior to the scheduled amortization of such up-front patent portfolio acquisition costs, resulting in the acceleration of amortization expense for the applicable patent-related assets. For the years ended December 31, 2012, 2011 and 2010, accelerated amortization expense related to the recovery of up-front patent acquisition costs totaled $10,574,000, $3,111,000 and $1,171,000, respectively.

For the years ended December 31, 2012, 2011 and 2010, pursuant to the terms of the respective inventor agreements, certain Acacia operating subsidiaries elected to terminate or sell their rights to patent portfolios, resulting in the acceleration of amortization expense for the patent-related assets totaling $2,823,000, $821,000 and $275,000, respectively.

For the years ended December 31, 2012, 2011 and 2010, patent costs and accumulated amortization related to patent-related sales and disposals are as follows (in thousands):



	2012	2011	2010

Patent costs	5,500	4,612	1,540
Accumulated amortization	2,466	3,509	1,108

For the years ended December 31, 2012, 2011 and 2010, patent proceeds and other costs related to patent-related sales and disposals are as follows (in thousands):



	2012	2011	2010

Proceeds	3,347	11,000	240
Other costs	—	4,717	94