Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
296 institutional managers reported holding CALX for the quarter ended Mar 31, 2026. Together they hold about 87% of shares outstanding; the top 10 hold 50%. 38 opened new positions; 66 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| BlackRock | 11.15M | 16.27% | $546.3M | trimmed -2.7% | ≤2013 |
| Vanguard Group | 8.74M | 12.75% | $428.1M | added +5.3% | ≤2013 |
| AllianceBernstein | 3.25M | 4.74% | $159.2M | added +122.3% | 2017 Q2 |
| State Street | 2.60M | 3.79% | $127.5M | added +10.1% | ≤2013 |
| Millennium Management | 1.90M | 2.78% | $93.3M | added +32% | 2022 Q4 |
| Congress Asset Management CO | 1.64M | 2.40% | $80.5M | added +13.6% | 2023 Q1 |
| Westfield Capital Management CO LP | 1.55M | 2.25% | $75.7M | added +35% | 2025 Q2 |
| Geode Capital | 1.44M | 2.09% | $70.3M | trimmed -0.7% | ≤2013 |
| Dimensional Fund Advisors | 1.22M | 1.78% | $59.7M | added +28.4% | ≤2013 |
| Loomis Sayles & CO L P | 840.2k | 1.23% | $41.2M | added +6.4% | 2025 Q2 |
| UBS | 802.8k | 1.17% | $39.3M | added +55% | ≤2013 |
| Acadian Asset Management | 800.3k | 1.17% | $39.2M | trimmed -22.3% | 2024 Q3 |
| Gilder Gagnon Howe & CO LLC | 779.1k | 1.14% | $38.2M | trimmed -12.3% | 2018 Q4 |
| Paradigm Capital Management INC/NY | 768.2k | 1.12% | $37.6M | added +14.2% | 2019 Q1 |
| Bank OF America CORP /DE/ | 750.1k | 1.09% | $36.7M | added +63.3% | ≤2013 |
| Mirae Asset Global Etfs Holdings LTD. | 719.5k | 1.05% | $35.2M | trimmed -9% | 2018 Q3 |
| Morgan Stanley | 712.2k | 1.04% | $34.9M | added +14.3% | ≤2013 |
| Charles Schwab Investment Management | 682.0k | 0.99% | $33.4M | added +1.3% | ≤2013 |
| Northern Trust | 609.7k | 0.89% | $29.9M | added +2.4% | ≤2013 |
| Harvey Partners, LLC (focused) | 572.5k | 0.83% | $28.0M | added +7.3% | 2024 Q4 |
| Nomura Asset Management International INC. | 557.0k | 0.81% | $27.3M | added +43.6% | 2025 Q4 |
| Arrowstreet Capital | 551.1k | 0.80% | $27.0M | trimmed -56.9% | 2024 Q1 |
| Renaissance Technologies | 543.4k | 0.79% | $26.6M | added +17.2% | ≤2013 |
| Wellington Management | 534.5k | 0.78% | $26.2M | trimmed -16.4% | 2018 Q3 |
| Artisan Partners | 529.9k | 0.77% | $26.0M | trimmed -10.2% | 2023 Q2 |
| Point72 | 513.8k | 0.75% | $25.2M | opened | 2025 Q1 |
| Squarepoint Ops LLC | 458.8k | 0.67% | $22.5M | added +259.1% | 2018 Q3 |
| Nuveen | 432.9k | 0.63% | $21.2M | added +7.3% | 2019 Q2 |
| Trexquant Investment LP | 429.4k | 0.63% | $21.0M | added +38.6% | 2024 Q4 |
| Citadel Advisors | 428.2k | 0.62% | $21.0M | added +834.1% | 2016 Q3 |
| Principal Financial Group INC | 395.3k | 0.58% | $19.4M | added +15.4% | 2020 Q4 |
| BNY Mellon | 387.5k | 0.56% | $19.0M | trimmed -4.5% | ≤2013 |
| Penn Capital Management Company, LLC | 378.6k | 0.55% | $18.5M | added +49.6% | 2025 Q1 |
| Jane Street | 351.9k | 0.51% | $17.2M | added +186.3% | 2025 Q2 |
| Divisar Capital Management LLC (focused) | 340.2k | 0.50% | $16.7M | added +13.4% | 2024 Q2 |
| Oberweis Asset Management INC/ | 335.0k | 0.49% | $16.4M | added +37% | 2025 Q4 |
| Federated Hermes, INC. | 317.1k | 0.46% | $15.5M | added +6.5% | 2025 Q3 |
| MetLife Investment Management, LLC | 312.4k | 0.46% | $15.3M | added +847.4% | 2017 Q4 |
| Goldman Sachs | 307.5k | 0.45% | $15.1M | trimmed -23.5% | ≤2013 |
| Divisadero Street Capital Management, LP | 305.7k | 0.45% | $15.0M | opened | 2024 Q4 |
| Rockefeller Capital Management L.p. | 299.6k | 0.44% | $14.7M | added +25.9% | 2023 Q4 |
| NEW York State Common Retirement Fund | 289.8k | 0.42% | $14.2M | added +36% | 2014 Q3 |
| Man Group | 280.3k | 0.41% | $13.7M | added +145.2% | 2025 Q3 |
| Schroder Investment Management Group | 277.9k | 0.41% | $13.6M | added +2350.8% | 2025 Q2 |
| Invesco | 272.9k | 0.40% | $13.4M | trimmed -52.8% | ≤2013 |
| SEI Investments CO | 269.3k | 0.39% | $13.2M | added +24.4% | 2020 Q2 |
| Deutsche Bank AG\ | 253.0k | 0.37% | $12.4M | added +13.8% | ≤2013 |
| Connor, Clark & Lunn Investment Management LTD. | 224.5k | 0.33% | $11.0M | added +3.5% | 2023 Q1 |
| Jacobs Levy Equity Management, INC | 221.9k | 0.32% | $10.9M | trimmed -47.9% | 2024 Q2 |
| Public Sector Pension Investment Board | 215.8k | 0.32% | $10.6M | added +3.4% | 2024 Q1 |
Largest 50 of 296 shown; the full ranked, searchable register is at boothcheck.com/holders/CALX. 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.