Stockholders' Equity	3 Months Ended
Mar. 31, 2019
Stockholders' Equity
Stockholders' Equity	10. Shareholders’ Equity Preferred Stock As of March 31, 2019 and December 31, 2018, there were 2,000,000 shares of preferred stock authorized and no shares of preferred stock issued or outstanding. Common Stock During the three months ended March 31, 2019, 30,000 vested employee stock options were exercised for cash proceeds of $147,900, at a weighted average exercise price of $4.93. Controlled Equity Offering On March 22, 2019, the Company entered into a sales agreement (the “Sales Agreement”) with Cantor Fitzgerald & Co. (the “Agent”), pursuant to which the Company may offer and sell from time to time shares of the Company’s common stock, no par value, through the Agent. The offering and sale of up to $40,000,000 of the shares has been registered under the Securities Act of 1933, as amended, pursuant to the Company’s registration statement on Form S-3 (File No. 333-227363), which was originally filed with the SEC on September 14, 2018 and declared effective by the SEC on October 1, 2018. The base prospectus contained within the registration statement, and a prospectus supplement that was filed with the SEC on March 22, 2019. Sales of the shares, if any, pursuant to the Sales Agreement, may be made in sales deemed to be a “at the market offering” as defined in Rule 415 (a)(14) of the Securities Act, including sales made directly through the Nasdaq Global Market or on any other existing trading market for the Company’s common stock. The Company intends to use the proceeds from the offering for working capital and other general corporate purposes. The Company may suspend or terminate the Sales Agreement at any time. During the three months ended March 31, 2019, the Company did not sell any shares of common stock under the Sales Agreement. As of March 31, 2019, $40 million of common stock remained available to be sold under this facility. Subsequent to March 31, 2019, the Company sold 437,043 shares of its common stock for gross proceeds of $2,296,235, at a weighted average selling price of approximately $5.25. The Company paid $57,406 in commissions related to the sale of the common shares. Restricted Common Stock During the three months ended March 31, 2019, 98,500 shares of common stock related to fully vested restricted stock units were delivered to an officer of the Company. The Company withheld 34,327 of these common shares at a fair value of $95,429 to cover the officer’s withholding taxes related to the vesting of restricted stock units.

10. Shareholders’ Equity

Preferred Stock

As of March 31, 2019 and December 31, 2018, there were 2,000,000 shares of preferred stock authorized and no shares of preferred stock issued or outstanding.

Common Stock

During the three months ended March 31, 2019, 30,000 vested employee stock options were exercised for cash proceeds of $147,900, at a weighted average exercise price of $4.93.

Controlled Equity Offering

On March 22, 2019, the Company entered into a sales agreement (the “Sales Agreement”) with Cantor Fitzgerald & Co. (the “Agent”), pursuant to which the Company may offer and sell from time to time shares of the Company’s common stock, no par value, through the Agent. The offering and sale of up to $40,000,000 of the shares has been registered under the Securities Act of 1933, as amended, pursuant to the Company’s registration statement on Form S-3 (File No. 333-227363), which was originally filed with the SEC on September 14, 2018 and declared effective by the SEC on October 1, 2018. The base prospectus contained within the registration statement, and a prospectus supplement that was filed with the SEC on March 22, 2019.

Sales of the shares, if any, pursuant to the Sales Agreement, may be made in sales deemed to be a “at the market offering” as defined in Rule 415 (a)(14) of the Securities Act, including sales made directly through the Nasdaq Global Market or on any other existing trading market for the Company’s common stock. The Company intends to use the proceeds from the offering for working capital and other general corporate purposes. The Company may suspend or terminate the Sales Agreement at any time.

During the three months ended March 31, 2019, the Company did not sell any shares of common stock under the Sales Agreement. As of March 31, 2019, $40 million of common stock remained available to be sold under this facility.

Subsequent to March 31, 2019, the Company sold 437,043 shares of its common stock for gross proceeds of $2,296,235, at a weighted average selling price of approximately $5.25. The Company paid $57,406 in commissions related to the sale of the common shares.

Restricted Common Stock

During the three months ended March 31, 2019, 98,500 shares of common stock related to fully vested restricted stock units were delivered to an officer of the Company. The Company withheld 34,327 of these common shares at a fair value of $95,429 to cover the officer’s withholding taxes related to the vesting of restricted stock units.