11. Net Loss Per Share Attributable to Common Shareholders

Basic net loss per share is calculated by dividing net loss attributable to common shareholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is calculated by adjusting net loss to remove the effects from potential dilutive common shares and dividing this adjusted amount by the weighted average number of common shares and potential dilutive common shares outstanding for the period. For purposes of the diluted net loss per share calculation, stock options, unvested restricted common shares, ESPP shares and shares issuable under an assumed conversion of the Notes are considered to be common stock equivalents but are excluded from the calculation of diluted net loss per share, as their effect would be anti-dilutive; therefore, basic and diluted net loss per share were the same for all periods presented as a result of the Company’s net loss. The Company’s net loss is net loss attributable to common shareholders for all periods presented.