13. Net Loss Per Share Attributable to Adaptive Biotechnologies Corporation Common Shareholders

Given the loss position for all periods presented, basic net loss per share attributable to our common shareholders is the same as diluted net loss per share attributable to our common shareholders, as the inclusion of all potential shares of common stock outstanding would have been anti-dilutive.

The number of weighted-average common stock equivalents excluded from the calculation of diluted net loss per share attributable to our common shareholders because of their anti-dilutive effect were 24.3 million and 28.8 million for the three months ended June 30, 2026 and 2025, respectively, and 25.0 million and 27.9 million for the six months ended June 30, 2026 and 2025, respectively. These common stock equivalents are comprised of shares that may be issued under our stock option, restricted stock, performance-based restricted stock and market-based restricted stock programs, as well as under the Notes using the if-converted method. The shares issuable in connection with a make-whole fundamental change were not considered common stock equivalents when calculating the number of weighted-average common stock equivalents excluded from the calculation of diluted net loss per share attributable to our common shareholders during the three and six months ended June 30, 2026.