Stockholders' Equity

3 Months Ended

Mar. 31, 2019

Stockholders’ Equity

Preferred stock and convertible preferred stock consist of the following:



	March 31, 2019		December 31, 2018
Preferred stock, $0.001 par value; 5,000,000 shares authorized at March 31, 2019 and December 31, 2018; no shares issued and outstanding at March 31, 2019 and December 31, 2018	$	—	$	—
Series B convertible preferred stock, $0.001 par value; 147,000 shares designated at March 31, 2019 and December 31, 2018; 200 shares issued and outstanding at March 31, 2019 and December 31, 2018	$	1	$	1
Series D convertible preferred stock, $0.001 par value; 21,300 shares designated at March 31, 2019 and December 31, 2018; 13,526.93 and 14,052.93 shares issued and outstanding at March 31, 2019 and December 31, 2018, respectively	$	13	$	14
Series E convertible preferred stock, $0.001 par value; 7,000 shares designated at March 31, 2019 and December 31, 2018; 1,340.80 and 3,260.70 shares issued and outstanding at March 31, 2019 and December 31, 2018, respectively	$	1	$	3

2019 equity activity

During the three months ended March 31, 2019, 526.00 shares of the Series D Preferred Stock were converted into a total of 200,000 shares of Common Stock and 1,919.90 shares of the Series E Preferred Stock were converted into a total of 730,000 shares of Common Stock.

2018 equity activity

During the three months ended March 31, 2018, 3,739.3 shares of the Series E Preferred Stock were converted into a total of 1,421,787 shares of Common Stock and 7,927.05 shares of the Series F Preferred Stock were converted into a total of 3,014,087 shares of Common Stock.