Exhibit 12.1

Computation of Ratio of Earnings to Combined Fixed Charges and Preferred Stock Dividends

(In thousands, except ratios)

	Year Ended December 31,														Six Months Ended June 30,
	2012			2013			2014		2015			2016			2017
Computation of earnings:
Net income (loss) from continuing operations before provision for income taxes	$	(33,906	)	$	(72,601	)	$	61,571	$	(57,605	)	$	(69,634	)	$	(43,578	)
Fixed charges, as calculated below		10,437			6,751			3,202		3,252			3,038			1,472
Total (losses) earnings	$	(23,469	)	$	(65,850	)	$	64,773	$	(54,353	)	$	(66,596	)	$	(42,106	)
Computation of fixed charges:
Interest expense, including amortization of debt issuance cost	$	10,313		$	6,610		$	3,090	$	3,060		$	2,825		$	1,363
Estimated interest expense portion of rental expense		124			141			112		192			213			109
Total fixed charges	$	10,437		$	6,751		$	3,202	$	3,252		$	3,038		$	1,472
Ratio of earnings to combined fixed charges and preferred stock dividends(1)		—			—			20.2:1		—			—			—

(1) Our earnings from continuing operations were inadequate to cover combined fixed charges and preferred stock dividends for the years ended December 31, 2012, 2013, 2015 and 2016 by $33.9 million, $72.6 million, $57.6 million and $69.6 million, respectively. Our earnings from continuing operations were inadequate to cover combined fixed charges and preferred stock dividends for the six months ended June 30, 2017 by $43.6 million.

For all periods presented above, we had no outstanding shares of preferred stock with required dividend payments.