Goodwill and Intangible Assets

The following sets forth goodwill and intangible assets by major asset class:



		December 31, 2018							December 31, 2017
	Useful Life (Yrs)	Gross		Accumulated Amortization			Net Book Value		Gross		Accumulated Amortization			Net Book Value
Indefinite lived:
Goodwill(a)		$	10,513,371	$	—		$	10,513,371	$	10,513,371	$	—		$	10,513,371
Definite lived:
Patents	8 – 17	5,802,528		(5,742,079		)	60,449		5,802,528		(5,681,673		)	120,855
Licenses	8 – 17	1,323,761		(1,219,357		)	104,404		1,323,761		(1,190,609		)	133,152
CELLECTRA^®(b)	5 – 11	8,106,270		(7,679,190		)	427,080		8,106,270		(7,252,108		)	854,162
GHRH(b)	11	335,314		(303,630		)	31,684		335,314		(271,948		)	63,366
Bioject (c)	2 – 15	5,100,000		(1,882,222		)	3,217,778		5,100,000		(1,405,556		)	3,694,444
Other(d)	18	4,050,000		(3,131,250		)	918,750		4,050,000		(2,906,250		)	1,143,750
Total intangible assets		24,717,873		(19,957,728		)	4,760,145		24,717,873		(18,708,144		)	6,009,729
Total goodwill and intangible assets		$	35,231,244	$	(19,957,728	)	$	15,273,516	$	35,231,244	$	(18,708,144	)	$	16,523,100


(a)	Goodwill was recorded from the Inovio AS acquisition in January 2005, the acquisition of VGX in June 2009 and the acquisition of Bioject in April 2016 for $3.9 million, $6.2 million and $400,000, respectively.


(b)	CELLECTRA^® and GHRH are developed technologies which were recorded from the acquisition of VGX.


(c)	Bioject intangible assets represent the estimated fair value of developed technology and intellectual property which were recorded from the Bioject asset acquisition.


(d)	Other intangible assets represent the estimated fair value of acquired intellectual property from the Inovio AS acquisition.

Aggregate amortization expense on intangible assets was $1.2 million, $1.6 million and $1.4 million for the years ended December 31, 2018, 2017 and 2016, respectively. Amortization expense related to intangible assets at December 31, 2018 is expected to be incurred as follows:



Year ending December 31,
2019	$	1,066,251
2020	547,081
2021	520,414
2022	492,818
2023	275,803
Thereafter	1,857,778
	$	4,760,145

There were no impairment or impairment indicators present and no losses were recorded during the years ended December 31, 2018, 2017 and 2016, respectively.