Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
274 institutional managers reported holding ATEC for the quarter ended Mar 31, 2026. Together they hold about 73% of shares outstanding; the top 10 hold 30%. 47 opened new positions; 55 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| BlackRock | 10.09M | 6.55% | $109.8M | trimmed -0.7% | ≤2013 |
| Vanguard Group | 6.97M | 4.52% | $75.8M | added +1.2% | ≤2013 |
| American Century Companies INC | 6.42M | 4.17% | $69.9M | trimmed -1.3% | 2023 Q2 |
| Royal Bank OF Canada | 4.52M | 2.93% | $49.1M | trimmed -8.1% | ≤2013 |
| BNP Paribas Financial Markets | 3.82M | 2.48% | $41.6M | trimmed -1.6% | 2019 Q2 |
| State Street | 3.03M | 1.97% | $33.0M | added +4.9% | 2019 Q2 |
| Geode Capital | 2.91M | 1.89% | $31.6M | added +2.8% | ≤2013 |
| Nuveen | 2.85M | 1.85% | $31.0M | trimmed -0.8% | 2019 Q2 |
| Millennium Management | 2.81M | 1.82% | $30.6M | added +26.2% | 2018 Q1 |
| Bank OF America CORP /DE/ | 2.56M | 1.66% | $27.9M | added +26.9% | ≤2013 |
| Point72 | 2.49M | 1.62% | $27.1M | added +126.7% | 2020 Q4 |
| Next Century Growth Investors LLC | 2.37M | 1.54% | $25.8M | trimmed -2% | 2019 Q2 |
| Hood River Capital Management LLC | 2.30M | 1.49% | $25.0M | added +102.1% | 2025 Q4 |
| UBS | 2.22M | 1.44% | $24.1M | added +32.3% | 2018 Q2 |
| Tremblant Capital Group | 2.19M | 1.42% | $23.8M | added +34.9% | 2025 Q4 |
| Braidwell LP | 2.17M | 1.41% | $23.6M | opened | 2024 Q2 |
| Two Sigma | 2.04M | 1.33% | $22.2M | added +3.8% | 2019 Q3 |
| Oberweis Asset Management INC/ | 1.91M | 1.24% | $20.8M | added +90.8% | 2025 Q3 |
| Cerity Partners LLC | 1.82M | 1.18% | $19.8M | unchanged | 2017 Q4 |
| Emerald Advisers, LLC | 1.81M | 1.17% | $19.7M | added +10.4% | 2023 Q4 |
| Goldman Sachs | 1.74M | 1.13% | $19.0M | trimmed -17.2% | 2019 Q3 |
| Morgan Stanley | 1.65M | 1.07% | $18.0M | trimmed -62% | 2015 Q4 |
| Penn Capital Management Company, LLC | 1.40M | 0.91% | $15.2M | added +30.2% | 2019 Q1 |
| AQR Capital | 1.39M | 0.90% | $15.1M | added +129.4% | 2019 Q3 |
| Northern Trust | 1.36M | 0.88% | $14.8M | trimmed -1.3% | 2017 Q1 |
| MetLife Investment Management, LLC | 1.33M | 0.86% | $14.4M | added +46.2% | 2019 Q3 |
| Deutsche Bank AG\ | 1.30M | 0.84% | $14.2M | trimmed -61% | ≤2013 |
| Aberdeen Group plc | 1.29M | 0.84% | $14.1M | unchanged | 2023 Q2 |
| Nomura Asset Management International INC. | 1.29M | 0.84% | $14.1M | added +45.2% | 2025 Q4 |
| Granite Investment Partners, LLC | 1.20M | 0.78% | $13.0M | added +4.7% | 2024 Q1 |
| NEW York State Common Retirement Fund | 1.18M | 0.77% | $12.9M | added +18.4% | 2019 Q2 |
| Emerald Mutual Fund Advisers Trust | 1.16M | 0.75% | $12.6M | added +27.1% | 2023 Q4 |
| Renaissance Technologies | 1.06M | 0.69% | $11.5M | added +21.3% | 2023 Q2 |
| Raymond James Financial INC | 1.01M | 0.65% | $10.9M | added +2681.1% | 2022 Q4 |
| Charles Schwab Investment Management | 978.1k | 0.64% | $10.6M | trimmed -1.8% | 2019 Q2 |
| King Luther Capital Management CORP | 944.8k | 0.61% | $10.3M | added +9.8% | 2021 Q2 |
| Jane Street | 878.5k | 0.57% | $9.6M | added +52.2% | 2021 Q3 |
| Citadel Advisors | 857.3k | 0.56% | $9.3M | trimmed -35.9% | 2019 Q4 |
| Motley Fool Asset Management LLC | 855.5k | 0.56% | $9.3M | added +58% | 2025 Q1 |
| Parkman Healthcare Partners LLC | 823.8k | 0.54% | $9.0M | added +197.2% | 2024 Q1 |
| Qube Research & Technologies LTD | 795.6k | 0.52% | $8.7M | added +597.8% | 2025 Q3 |
| Schonfeld Strategic Advisors | 766.4k | 0.50% | $8.3M | added +509.1% | 2019 Q3 |
| First Eagle Investment Management | 696.6k | 0.45% | $7.6M | added +3% | 2024 Q2 |
| Intrinsic Edge Capital Management LLC | 649.4k | 0.42% | $7.1M | added +30.1% | 2023 Q1 |
| Squarepoint Ops LLC | 607.1k | 0.39% | $6.6M | added +61.4% | 2020 Q1 |
| SEI Investments CO | 598.0k | 0.39% | $6.5M | added +62.2% | 2020 Q4 |
| Motley Fool Wealth Management, LLC | 575.8k | 0.37% | $6.3M | trimmed -31.2% | 2025 Q1 |
| Arrowstreet Capital | 507.0k | 0.33% | $5.5M | added +102.3% | 2025 Q4 |
| Trexquant Investment LP | 457.2k | 0.30% | $5.0M | added +8.9% | 2025 Q1 |
| First Trust Advisors LP | 447.1k | 0.29% | $4.9M | trimmed -18.1% | 2025 Q1 |
Largest 50 of 274 shown; the full ranked, searchable register is at boothcheck.com/holders/ATEC. Related filers are grouped using the filings' own included-manager declarations. Historically, several managers opening new positions in the same quarter said almost nothing about the quarter that followed (59,118 cases since 2013). A filed record, not a forecast. Nothing here is investment advice.