Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
316 institutional managers reported holding NWN for the quarter ended Mar 31, 2026. Together they hold about 79% of shares outstanding; the top 10 hold 45%. 49 opened new positions; 41 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| BlackRock | 6.38M | 15.27% | $340.1M | trimmed -6.3% | ≤2013 |
| Vanguard Group | 4.81M | 11.51% | $256.5M | added +2.3% | ≤2013 |
| State Street | 1.61M | 3.84% | $85.5M | trimmed -22.5% | ≤2013 |
| Vaughan Nelson Investment Management, L.p. | 1.19M | 2.84% | $63.4M | trimmed -14.6% | 2025 Q2 |
| Geode Capital | 1.03M | 2.47% | $55.0M | added +4.3% | ≤2013 |
| Morgan Stanley | 831.4k | 1.99% | $44.3M | trimmed -9% | ≤2013 |
| Invesco | 800.0k | 1.91% | $42.6M | added +29.4% | ≤2013 |
| First Trust Advisors LP | 755.9k | 1.81% | $40.3M | trimmed -12% | ≤2013 |
| Dimensional Fund Advisors | 743.5k | 1.78% | $39.6M | added +2.6% | ≤2013 |
| Goldman Sachs | 656.2k | 1.57% | $35.0M | added +11.8% | ≤2013 |
| Duff & Phelps Investment Management CO | 613.1k | 1.47% | $32.7M | trimmed -28.4% | ≤2013 |
| William Blair Investment Management, LLC | 594.2k | 1.42% | $31.7M | added +3.3% | 2025 Q4 |
| Charles Schwab Investment Management | 583.0k | 1.39% | $31.1M | trimmed -2.2% | ≤2013 |
| GAMCO (Gabelli) | 520.0k | 1.24% | $27.7M | unchanged | ≤2013 |
| Nuveen | 502.5k | 1.20% | $26.8M | added +75.5% | 2019 Q2 |
| BNY Mellon | 476.5k | 1.14% | $25.4M | trimmed -1.5% | ≤2013 |
| Northern Trust | 456.3k | 1.09% | $24.3M | added +4.1% | ≤2013 |
| Victory Capital Management INC | 417.9k | 1.00% | $22.3M | added +161.4% | 2019 Q3 |
| MetLife Investment Management, LLC | 370.7k | 0.89% | $19.7M | unchanged | 2017 Q4 |
| Gamco Investors, INC. et al | 363.7k | 0.87% | $19.4M | unchanged | 2014 Q1 |
| Mirae Asset Global Etfs Holdings LTD. | 311.6k | 0.74% | $16.6M | trimmed -13.3% | 2022 Q3 |
| Two Sigma | 273.2k | 0.65% | $14.6M | added +370.5% | 2025 Q2 |
| UBS | 271.9k | 0.65% | $14.5M | added +22.6% | ≤2013 |
| Hotchkis & Wiley Capital Management LLC | 270.0k | 0.65% | $14.4M | trimmed -6.7% | 2022 Q4 |
| Glenmede Trust CO NA | 267.8k | 0.64% | $14.3M | trimmed -8.5% | 2024 Q3 |
| Prudential Financial INC | 241.6k | 0.58% | $12.9M | trimmed -17.5% | ≤2013 |
| Legal & General Group PLC | 241.3k | 0.58% | $12.9M | trimmed -5.8% | ≤2013 |
| Principal Financial Group INC | 238.7k | 0.57% | $12.7M | trimmed -21.8% | ≤2013 |
| Natixis Advisors, LLC | 225.3k | 0.54% | $12.0M | trimmed -16.7% | 2024 Q4 |
| American Century Companies INC | 223.1k | 0.53% | $11.9M | added +2.4% | 2022 Q1 |
| AQR Capital | 222.3k | 0.53% | $11.8M | added +3.6% | 2021 Q2 |
| Thompson Siegel & Walmsley LLC | 207.1k | 0.49% | $11.0M | trimmed -35% | 2024 Q3 |
| Edgestream Partners, L.p. | 201.7k | 0.48% | $10.7M | added +54.1% | 2025 Q4 |
| SG Americas Securities, LLC | 193.2k | 0.46% | $10.3M | added +17% | 2016 Q1 |
| Bank OF America CORP /DE/ | 191.5k | 0.46% | $10.2M | trimmed -21% | ≤2013 |
| Jupiter Asset Management LTD | 188.4k | 0.45% | $10.0M | opened | 2026 Q1 |
| Baird Financial Group, INC. | 172.7k | 0.41% | $9.2M | added +40.7% | 2025 Q4 |
| Dana Investment Advisors, INC. | 166.7k | 0.40% | $8.9M | unchanged | 2024 Q1 |
| Ameriprise Financial INC | 160.2k | 0.38% | $8.5M | trimmed -4% | ≤2013 |
| Franklin Resources | 154.5k | 0.37% | $8.2M | added +424.6% | 2021 Q3 |
| Public Sector Pension Investment Board | 148.5k | 0.35% | $7.9M | added +3.4% | ≤2013 |
| Exchange Traded Concepts, LLC | 142.0k | 0.34% | $7.6M | added +1.8% | 2022 Q1 |
| ProShare Advisors LLC | 130.5k | 0.31% | $6.9M | trimmed -7.7% | ≤2013 |
| HRT Financial LP | 128.7k | 0.31% | $6.9M | added +198.7% | 2024 Q3 |
| Rhumbline Advisers | 122.4k | 0.29% | $6.5M | added +1.5% | ≤2013 |
| Millennium Management | 107.9k | 0.26% | $5.8M | trimmed -49% | 2023 Q1 |
| Qube Research & Technologies LTD | 97.2k | 0.23% | $5.2M | opened | 2026 Q1 |
| Voya Investment Management LLC | 97.0k | 0.23% | $5.2M | trimmed -10.9% | ≤2013 |
| CSM Advisors, LLC | 96.5k | 0.23% | $5.1M | added +6% | 2025 Q2 |
| Point72 | 95.1k | 0.23% | $5.1M | opened | 2026 Q1 |
Largest 50 of 316 shown; the full ranked, searchable register is at boothcheck.com/holders/NWN. 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.