Intangible Assets

Intangible assets consisted of the following at December 31:



	2016			2015

Product and license rights	$	20,543,262		$	18,011,362
Less: accumulated amortization	(4,988,333		)	(3,541,305		)
Total product and license rights	15,554,929			14,470,057
Patents	8,844,994			8,236,719
Less: accumulated amortization	(2,298,442		)	(1,551,430		)
Total patents	6,546,552			6,685,289
Trademarks	61,715			22,270
Less: accumulated amortization	(9,020		)	(9,020		)
Total trademarks	52,695			13,250
Total intangible assets	$	22,154,176		$	21,168,596

In February 2014, the Company acquired the rights of the branded prescription product Vaprisol from Astellas (discussed more fully in Note 3). The intangible asset value is $3.0 million and is included in product and license rights. The asset will be amortized through February 2022, the remaining expected useful life of the acquired asset, which coincides with the life of the primary intellectual property asset.

During 2013, the Company entered into an agreement with Pernix to distribute and promote the branded prescription product Omeclamox-Pak. The $4.0 million upfront payment the Company paid to Pernix Therapeutics on October 29, 2013 (discussed more fully in Note 3) is included in product and license rights and will be amortized through June 2032, the remaining expected useful life of the acquired asset.

In 2011, the Company acquired the Kristalose trademark and FDA registration from Mylan Inc. The agreement requires the Company to make future quarterly payments over a seven-year period equal to a percentage of Kristalose net sales. The payments are being treated as consideration for the assets acquired and are being capitalized and amortized over the remaining expected useful life of the acquired asset, currently through 2026. During 2016 and 2015, the Company paid $1.4 million and $1.5 million, respectively, to Mylan Inc. in Kristalose payments.

In November 2016, the Company acquired the U.S. rights to Nordic Group B.V.’s innovative injectable methotrexate product line. The agreement requires the Company to make future milestone payments over a fifteen-year period from the effective grant of the Regulatory Approval of the Methotrexate Pre-Filled Syringe Product in the U.S. The payments are being treated as consideration for the assets acquired and are being capitalized and will be amortized over the expected useful life of the acquired asset, once approval is granted. During 2016, the Company paid a deposit of $100,000 as well as recorded a liability of $900,000 provided through 180,000 unvested restricted shares of Cumberland stock, valued on November 15, 2016, that will fully vest upon the FDA approval of the first Nordic product. As of December 31, 2016, the 180,000 shares of unvested restricted Cumberland stock are valued at $990,000.

During 2016 and 2015, the Company recorded an additional $0.6 million and $0.1 million, respectively, in intangible assets for patents, trademarks and capitalized patent costs, including amounts incurred in the protection of the Company's intellectual property. These costs will be amortized over the remaining expected useful life of the associated patents.

Amortization expense related to product and license rights, trademarks and patents was $2.2 million, $2.0 million and $1.6 million during 2016, 2015 and 2014, respectively. The expected amortization expense for the Company's current balance of intangible assets are as follows:



Year ending December 31:
2017	$	2,320,093
2018	2,338,260
2019	2,392,760
2020	2,392,760
2021 and thereafter	12,710,303
	$	22,154,176