Stockholders' equity Stockholders' equity

12 Months Ended

Dec. 31, 2018

Stockholders' Equity Note Disclosure [Text Block]

Stockholders’ equity

Common stock. The Company has two classes of authorized common stock: Class A common stock with 500 million shares authorized and Class B common stock with 150 million shares authorized. As of December 31, 2018, 105.2 million shares of Class A stock were issued and outstanding and 35.9 million shares of Class B stock were issued and outstanding. The rights of the holders of Class A and Class B common stock are identical, except with respect to voting power and conversion rights. Each share of Class A common stock is entitled to one vote per share and each share of Class B common stock is entitled to ten votes per share. Each share of Class B common stock is convertible at any time at the option of the stockholder into one share of Class A common stock and has no expiration date. The Class B common stock is also convertible into Class A common stock on the same basis upon any transfer, whether or not for value, except for “permitted transfers” as defined in the Company’s restated certificate of incorporation. Each share of Class B common stock will convert automatically into one share of Class A common stock upon the date when the outstanding shares of Class B common stock represent less than 10% of the aggregate number of shares of common stock then outstanding. As of December 31, 2018, the Class B stock continued to represent greater than 10% of the overall outstanding shares.

The Company had the following shares of common stock reserved for issuance upon the exercise of equity instruments as of December 31, 2018:



(in thousands)	December 31, 2018
Stock options outstanding	5,993
Restricted stock units outstanding	7,217
Performance stock units outstanding	300
Common stock available for future grants	31,421
Total common stock shares reserved for issuance	44,931