Ranked by reported Q2 2026 13F market value
Share of total reported institutional value in CALX held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 11.8M | $439.5M | +5.6% | 18.702% | 0.01% |
| 2 | VANGUARD PORTFOLIO MANAGEMENT LLC | 5.6M | $208.5M | +1.0% | 8.875% | 0.01% |
| 3 | ALLIANCEBERNSTEIN L.P. | 3.2M | $159.1M | -0.1% | 5.159% | 0.05% |
| 4 | STATE STREET CORP | 2.9M | $108.8M | +12.0% | 4.630% | 0.00% |
| 5 | VANGUARD CAPITAL MANAGEMENT LLC | 2.6M | $96.6M | -3.7% | 4.109% | 0.00% |
| 6 | GEODE CAPITAL MANAGEMENT, LLC | 1.5M | $55.3M | +3.2% | 2.353% | 0.00% |
| 7 | WESTFIELD CAPITAL MANAGEMENT CO LP | 1.3M | $49.4M | -14.3% | 2.104% | 0.16% |
| 8 | DIMENSIONAL FUND ADVISORS LP | 1.3M | $48.9M | +7.5% | 2.080% | 0.01% |
| 9 | CITADEL ADVISORS LLC | 1.2M | $46.6M | +169.2% | 1.981% | 0.00% |
| 10 | PARADIGM CAPITAL MANAGEMENT INC/NY | 997K | $37.2M | +29.8% | 1.584% | 1.01% |
| 11 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | 876K | $32.7M | +58.9% | 1.391% | 0.01% |
| 12 | UBS Group AG | 857K | $32.0M | +32.9% | 1.362% | 0.00% |
| 13 | LOOMIS SAYLES & CO L P | 785K | $29.3M | -6.6% | 1.246% | 0.04% |
| 14 | MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | 753K | $28.1M | +8.1% | 1.196% | 0.03% |
| 15 | JANE STREET GROUP, LLC | 727K | $27.1M | +104.0% | 1.155% | 0.00% |
| 16 | TWO SIGMA INVESTMENTS, LP | 704K | $26.3M | +336.0% | 1.118% | 0.02% |
| 17 | MILLENNIUM MANAGEMENT LLC | 699K | $26.1M | -63.3% | 1.110% | 0.01% |
| 18 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 697K | $26.0M | +2.2% | 1.107% | 0.00% |
| 19 | NOMURA ASSET MANAGEMENT INTERNATIONAL INC. | 660K | $24.6M | +18.4% | 1.048% | 0.04% |
| 20 | NORTHERN TRUST CORP | 642K | $24.0M | +5.3% | 1.020% | 0.00% |
| 21 | GILDER GAGNON HOWE & CO LLC | 580K | $21.7M | -25.5% | 0.922% | 0.22% |
| 22 | BANK OF AMERICA CORP /DE/ | 560K | $20.9M | -25.3% | 0.889% | 0.00% |
| 23 | RENAISSANCE TECHNOLOGIES LLC | 548K | $20.5M | +0.9% | 0.870% | 0.03% |
| 24 | MORGAN STANLEY | 525K | $19.6M | -26.3% | 0.834% | 0.00% |
| 25 | WELLINGTON MANAGEMENT GROUP LLP | 519K | $19.4M | -2.9% | 0.825% | 0.00% |
denotes a marquee investor (Buffett, Burry, ARK, Tiger Global, Pershing Square, Baupost and other widely-followed managers). β% of Fundβ shows how much of that investorβs total 13F portfolio is invested in CALX β a direct measure of their conviction.
Filings activity in CALX during Q2 2026, grouped by how each filer changed its position.
Institutions that opened a new CALX position in Q2 2026
Institutions that fully closed their CALX position in Q2 2026
8 quarters of 13F filings Β· Ξ columns show change vs prior quarter
| Quarter | Inst. Holders | Ξ Holders | Ownership % | Ξ Ownership | Total 13F Value | Ξ Value |
|---|---|---|---|---|---|---|
| Q2 2026 | 286 | 7.1% | 95.25% | +2.60 pp | $2.19B | 23% |
| Q1 2026 | 308 | 6.1% | 92.65% | +4.53 pp | $2.85B | 3.4% |
| Q4 2025 | 328 | +5.1% | 88.12% | +2.47 pp | $2.95B | 9.3% |
| Q3 2025 | 312 | +6.8% | 85.65% | +0.77 pp | $3.26B | +15% |
| Q2 2025 | 292 | +15% | 84.88% | 1.28 pp | $2.82B | +44% |
| Q1 2025 | 254 | +2.0% | 86.16% | +0.10 pp | $1.97B | +0.1% |
| Q4 2024 | 249 | +5.5% | 86.06% | 0.23 pp | $1.96B | 11% |
| Q3 2024 | 236 | β | 86.29% | β | $2.20B | β |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Ξ columns compare to the immediately prior filed quarter.
Quick answers to the most common questions about buying CALX stock.
Based on Q2 2026 13F filings, institutional ownership of Calix, Inc. stands at 95.3%, held across 286 reporting institutions.
BlackRock, Inc. is the largest reported institutional holder of CALX, with approximately 11,775,490 shares worth $0.44B as of Q2 2026.
Yes β 5 widely-followed marquee investors appear among the top 25 institutional holders of CALX, including CITADEL ADVISORS LLC, JANE STREET GROUP, LLC, TWO SIGMA INVESTMENTS, LP, MILLENNIUM MANAGEMENT LLC, RENAISSANCE TECHNOLOGIES LLC.
Our composite Smart Money Score for CALX is 69 out of 100 (Bullish). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
35 institutions opened new positions in CALX during Q2 2026, while 58 fully exited. 51 added to existing positions and 195 trimmed.
CALX institutional ownership rose by 2.60 percentage points quarter-over-quarter, with a net change of -22 holders.
The top 10 institutions account for 57.1% of all reported 13F value in CALX, and the top 25 account for 74.4%.
All data is sourced from SEC Form 13F filings, which institutional investment managers with at least $100M in assets are required to file each quarter. We process every 13F filing from EDGAR and recompute the aggregates after each cycle. Insider transactions are sourced from Form 4 filings.
Calix, Inc. (CALX) Institutional Ownership