8. Convertible Senior Secured Notes

The table below summarizes activity related to the Notes from issuance on May 3, 2013 through June 30, 2016, in thousands:

Gross proceeds	$	90,000
Initial value of interest make-whole derivative reported as debt discount	(9,270		)
Conversion option reported as debt discount and APIC	(22,336		)
Conversion of debt to equity - principal	(81,463		)
Conversion of debt to equity - accretion of debt discount and deferred financing costs	25,003
Accretion of debt discount and deferred financing costs	5,151

December 31, 2015 carrying value	7,085

Conversion of debt to equity - principal	(1,962		)
Conversion of debt to equity - accretion of debt discount and deferred financing costs	424
Accretion of debt discount and deferred financing costs	152

June 30, 2016 carrying value, unaudited	$	5,699

During the six month period ended June 30, 2016, approximately $2.0 million of the Notes were presented to the Company for conversion. Accordingly, the Company issued approximately 0.4 million shares of common stock in conversion of the principal amount of the Notes. As a result of the conversions, the Company incurred a loss of approximately $0.4 million on extinguishment of debt during the six months ended June 30, 2016, which is included as a separate component of other income (expense) on the Consolidated Statement of Operations. During the six month period ended June 30, 2015, as a result of approximately $25.3 million in note conversions, the Company incurred a loss of approximately $2.4 million on extinguishment of debt.