| 13.32% | % of Shares Held by All Insider |
| 79.73% | % of Shares Held by Institutions |
| 91.98% | % of Float Held by Institutions |
| 119 | Number of Institutions Holding Shares |
| Holder | Shares | Date Reported | % Out | Value |
|---|---|---|---|---|
| TRV GP II, LLC | 10,230,349 | Dec 30, 2018 | 31.03% | 34,476,276 |
| TRV GP III, LLC | 3,048,780 | Dec 30, 2018 | 9.25% | 10,274,388 |
| Wellington Management Company, LLP | 1,510,754 | Dec 30, 2018 | 4.58% | 5,091,240 |
| Blackrock Inc. | 1,065,339 | Dec 30, 2018 | 3.23% | 3,590,192 |
| FMR, LLC | 1,007,115 | Dec 30, 2018 | 3.05% | 3,393,977 |
| JP Morgan Chase & Company | 620,148 | Dec 30, 2018 | 1.88% | 2,089,898 |
| Omega Fund Management (US) Inc. | 529,965 | Dec 30, 2018 | 1.61% | 1,785,982 |
| Vanguard Group, Inc. (The) | 477,871 | Dec 30, 2018 | 1.45% | 1,610,425 |
| Dimensional Fund Advisors LP | 456,865 | Dec 30, 2018 | 1.39% | 1,539,635 |
| Two Sigma Investments, LP | 401,932 | Dec 30, 2018 | 1.22% | 1,354,510 |
| Holder | Shares | Date Reported | % Out | Value |
|---|---|---|---|---|
| Fidelity Select Portfolios - Biotechnology | 715,474 | Feb 27, 2019 | 2.17% | 3,183,859 |
| Vanguard Total Stock Market Index Fund | 444,633 | Sep 29, 2018 | 1.35% | 2,890,114 |
| iShares Russell 2000 ETF | 349,812 | Feb 27, 2019 | 1.06% | 1,556,663 |
| DFA U.S. Small Cap Series | 207,557 | Oct 30, 2018 | 0.63% | 838,530 |
| Fidelity Growth Company Fund | 144,933 | Feb 27, 2019 | 0.44% | 644,951 |
| iShares Russell 2000 Growth ETF | 140,782 | Feb 27, 2019 | 0.43% | 626,479 |
| Bridgeway Funds Inc-Ultra Small Company Market Fund | 115,000 | Sep 29, 2018 | 0.35% | 747,500 |
| Vanguard Variable Insurance Fund-Small Company Growth | 99,674 | Sep 29, 2018 | 0.30% | 647,881 |
| Vanguard Extended Market Index Fund | 96,348 | Sep 29, 2018 | 0.29% | 626,262 |
| Russell Inv Co-U.S. Small Cap Equity Fund | 94,752 | Jul 30, 2018 | 0.29% | 668,949 |