Ranked by reported Q1 2026 13F market value
Share of total reported institutional value in OII held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 16.3M | $579.9M | +2.2% | 16.391% | 0.01% |
| 2 | VANGUARD PORTFOLIO MANAGEMENT LLC | 7.6M | $268.8M | — | 7.598% | 0.01% |
| 3 | BROWN ADVISORY INC | 5.8M | $205.3M | -22.1% | 5.803% | 0.34% |
| 4 | STATE STREET CORP | 5.0M | $178.6M | +8.3% | 5.047% | 0.01% |
| 5 | VANGUARD CAPITAL MANAGEMENT LLC | 4.5M | $158.9M | — | 4.490% | 0.00% |
| 6 | AMERICAN CENTURY COMPANIES INC | 3.8M | $133.6M | +4.4% | 3.776% | 0.07% |
| 7 | EARNEST PARTNERS LLC | 3.7M | $130.7M | -2.8% | 3.694% | 0.54% |
| 8 | DIMENSIONAL FUND ADVISORS LP | 3.5M | $122.8M | -0.4% | 3.471% | 0.03% |
| 9 | Morgan Stanley Institutional Investment Advisors LLC | 3.5M | $122.5M | -12.5% | 3.462% | 11.81% |
| 10 | Neuberger Berman Group LLC | 3.2M | $114.2M | -3.5% | 3.227% | 0.09% |
| 11 | GEODE CAPITAL MANAGEMENT, LLC | 2.4M | $84.3M | +3.1% | 2.382% | 0.01% |
| 12 | Greenhouse Funds LLLP | 2.0M | $72.1M | -17.6% | 2.038% | 3.55% |
| 13 | LOOMIS SAYLES & CO L P | 1.7M | $60.3M | -7.2% | 1.705% | 0.08% |
| 14 | BARROW HANLEY MEWHINNEY & STRAUSS LLC | 1.4M | $50.4M | — | 1.425% | 0.17% |
| 15 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 1.4M | $49.1M | -4.1% | 1.387% | 0.01% |
| 16 | NORTHERN TRUST CORP | 1.3M | $45.0M | +4.2% | 1.271% | 0.01% |
| 17 | ROYAL BANK OF CANADA | 1.0M | $37.2M | -14.2% | 1.051% | 0.01% |
| 18 | MORGAN STANLEY | 1.0M | $36.9M | -0.1% | 1.043% | 0.00% |
| 19 | GOLDMAN SACHS GROUP INC | 1000K | $35.5M | -21.5% | 1.002% | 0.00% |
| 20 | Boston Partners | 855K | $30.3M | — | 0.857% | 0.03% |
| 21 | FRANKLIN RESOURCES INC | 828K | $29.4M | +85.7% | 0.831% | 0.01% |
| 22 | Ranger Investment Management, L.P. | 797K | $28.3M | -0.8% | 0.799% | 2.04% |
| 23 | Fisher Asset Management, LLC | 792K | $28.1M | -0.1% | 0.794% | 0.01% |
| 24 | Bank of New York Mellon Corp | 755K | $26.8M | -1.9% | 0.757% | 0.00% |
| 25 | Goehring & Rozencwajg Associates, LLC | 714K | $25.3M | +25.5% | 0.715% | 1.36% |
denotes a marquee investor (Buffett, Burry, ARK, Tiger Global, Pershing Square, Baupost and other widely-followed managers). “% of Fund” shows how much of that investor’s total 13F portfolio is invested in OII — a direct measure of their conviction.
Filings activity in OII during Q1 2026, grouped by how each filer changed its position.
8 quarters of 13F filings · Δ columns show change vs prior quarter
| Quarter | Inst. Holders | Δ Holders | Ownership % | Δ Ownership | Total 13F Value | Δ Value |
|---|---|---|---|---|---|---|
| Q1 2026 | 356 | +16% | 87.36% | +28.02 pp | $3.43B | +47% |
| Q4 2025 | 308 | +4.1% | 59.34% | +0.82 pp | $2.33B | +1.4% |
| Q3 2025 | 296 | +3.9% | 58.52% | +9.66 pp | $2.30B | +20% |
| Q2 2025 | 285 | +1.8% | 48.86% | 1.63 pp | $1.92B | 3.2% |
| Q1 2025 | 280 | 0.7% | 50.49% | 12.10 pp | $1.98B | 19% |
| Q4 2024 | 282 | +11% | 62.59% | +2.81 pp | $2.46B | +4.7% |
| Q3 2024 | 253 | +8.1% | 59.78% | +3.10 pp | $2.35B | +5.5% |
| Q2 2024 | 234 | — | 56.68% | — | $2.23B | — |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Δ columns compare to the immediately prior filed quarter.
Quick answers to the most common questions about buying OII stock.
Based on Q1 2026 13F filings, institutional ownership of Oceaneering International, Inc. stands at 87.4%, held across 356 reporting institutions.
BlackRock, Inc. is the largest reported institutional holder of OII, with approximately 16,348,842 shares worth $0.58B as of Q1 2026.
Yes — 1 widely-followed marquee investor appear among the top 25 institutional holders of OII, including Fisher Asset Management, LLC.
Our composite Smart Money Score for OII is 68 out of 100 (Bullish). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
90 institutions opened new positions in OII during Q1 2026, while 42 fully exited. 237 added to existing positions and 27 trimmed.
OII institutional ownership rose by 28.02 percentage points quarter-over-quarter, with a net change of +48 holders.
The top 10 institutions account for 58.7% of all reported 13F value in OII, and the top 25 account for 77.3%.
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.
Oceaneering International, Inc. (OII) Institutional Ownership