Major Customers and Concentration of Credit Risk

12 Months Ended

Dec. 31, 2017

Major Customers and Concentration of Credit Risk



Customer	2017 Revenue		% of Total Revenue		2016 Revenue		% of Total Revenue		2015 Revenue		% of Total Revenue
MedImmune	$	22,269,773	53	%	$	1,518,639	4	%	$	16,037,731	40	%
DARPA	9,983,927		24		26,602,183		75		11,582,623		28
Roche	6,107,254		14		4,917,929		14		10,778,688		27
NIAID	—		—		118,171		—		901,475		2
GeneOne (affiliated entity)	551,208		1		1,188,432		4		450,000		1
All other	3,307,924		8		1,023,007		3		821,594		2
Total revenue	$	42,220,086	100	%	$	35,368,361	100	%	$	40,572,111	100	%

During the years ended December 31, 2017, 2016 and 2015, the Company recognized revenue from various license fees, collaborative research and development agreements, grants and government contracts. As of December 31, 2017, $4.1 million, or 69%, and $1.7 million, or 28%, of the Company's accounts receivable was attributable to DARPA and MedImmune, respectively. As of December 31, 2016, $12.1 million, or 73%, $2.4 million, or 15%, and $1.2 million, or 7%, of accounts receivable was attributable to DARPA, Roche and MedImmune, respectively.

The Company’s accounts receivable from DARPA includes $1.6 million of amounts that are unbilled as of December 31, 2017. Unbilled amounts range from 1 to 9 months in age and are attributable to the fact that the Company is awaiting an invoice from its sub-contractor prior to submission of an aggregate invoice to DARPA. The Company believes that all criteria for revenue recognition under SAB 104 have been met, and also anticipates that all such amounts will be invoiced and collected within the next 12 months and has included these amounts as current assets in its consolidated balance sheet.

There is minimal credit risk with these customers based upon collection history, their size and financial condition. Accordingly, the Company does not consider it necessary to record a reserve for uncollectible accounts receivable.