Convertible 3.75% Senior Notes

On December 16, 2014, the Company issued $125 million aggregate principal amount of 3.75% Convertible Senior Notes due 2019 (the “ 2019 Notes”). On December 22, 2014, the Company announced the closing of the initial purchasers’ exercise in full of their option to purchase an additional $18.75 million aggregate principal amount of Notes. The 2019 Notes bear interest at a fixed rate of 3.75% per year, payable semiannually in arrears on June 15 and December 15 of each year, beginning on June 15, 2015, and mature on December 15, 2019, unless earlier repurchased, redeemed or converted. The 2019 Notes are convertible into shares of the Company’s common stock, cash or a combination thereof. On May 20, 2015, the Company received shareholder approval for the increase in the number of shares of common stock authorized and available for issuance upon conversion of the Notes.

The remaining unamortized discount and unamortized debt financing costs will be amortized over the remaining term of the debt of 1.75 years. At March 31, 2018 and December 31, 2017, the net carrying amount of the 2019 Notes and the remaining unamortized debt discount were as follows (in thousands):



	March 31, 2018		December 31, 2017
	(Unaudited)		(Audited)
Face amount of the 2019 Notes	$	143,750	$	143,750
Unamortized discount	18,178		20,517
Debt issuance costs	$	2,001	$	2,256
Carrying amount of the 2019 Notes	$	123,571	$	120,977

For the three months ended March 31, 2018 and 2017, the Company recorded the following expenses in relation to the 2019 Notes (in thousands):



	Three months ended March 31,
	2018		2017
Interest Expense at 3.75% coupon rate	$	1,348	$	1,348
Debt discount amortization	2,339		2,057
Amortization of deferred financing costs	255		224
Total interest expense (1)	$	3,942	$	3,629

(1) Included within "Interest and other expense, net" on the Condensed Consolidated Statements of Operations, offset by interest income and capitalized interest

On April 27, 2018, the Company announced it had entered into separate, privately negotiated exchange agreements with certain holders of Teligent’s 3.75% Senior Convertible Notes due 2019. See note 12 for more detailed information on this subsequent event.