OII Institutional Ownership & Shareholders
OCEANEERING INTL INC (OII) is currently held by 367 institutional investors tracked by InsiderSet, with a combined reported market value of approximately $4.06B based on the latest available SEC Form 13F filings for the quarter ended June 30, 2026.
Blackrock, Inc. is currently the largest disclosed institutional shareholder of OII tracked by InsiderSet, reporting ownership valued at approximately $664.66M in its June 30, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $670.24M, representing an estimated gain of +0.84% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 56% of the total disclosed OII value among the investors covered in this analysis. Major shareholders include Blackrock, Inc., Vanguard Portfolio Management Llc, State Street Corp, and several other long-term asset managers with concentrated positions in OCEANEERING INTL INC (OII).
This page ranks the largest institutional OII shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
Institutional Holders
367
Total Reported Value
$4.06B
Largest Holder
Blackrock, Inc.
Largest Position
$664.66M
Insider Transactions (90d)
3
Latest Filing Quarter
Q2 2026
New Institutional Positions
55
Funds Exiting Positions
0
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Blackrock, Inc. | 0.01% | 16,403,230 | $664,658,871 | $670,235,978 | +$5,577,107 | +0.84% | |
| Vanguard Portfolio Management Llc | 0.01% | 7,926,938 | $321,199,528 | $323,894,687 | +$2,695,159 | +0.84% | |
| State Street Corp | 0.01% | 4,994,403 | $202,373,210 | $204,071,307 | +$1,698,097 | +0.84% | |
| Brown Advisory Inc | 0.31% | 4,967,307 | $201,275,310 | $202,964,164 | +$1,688,854 | +0.84% | |
| Vanguard Capital Management Llc | 0.00% | 4,485,268 | $181,743,059 | $183,268,050 | +$1,524,991 | +0.84% | |
| American Century Companies Inc | 0.07% | 4,023,994 | $163,052,237 | $164,420,395 | +$1,368,158 | +0.84% | |
| Earnest Partners Llc | 0.52% | 3,547,295 | $143,736,393 | $144,942,474 | +$1,206,081 | +0.84% | |
| Dimensional Fund Advisors Lp | 0.03% | 3,546,908 | $143,711,903 | $144,926,661 | +$1,214,758 | +0.85% | |
| Morgan Stanley Institutional Investment Advisors Llc | 11.60% | 3,066,015 | $124,234,908 | $125,277,373 | +$1,042,465 | +0.84% | |
| Geode Capital Management, Llc | 0.01% | 2,839,554 | $115,079,025 | $116,024,176 | +$945,151 | +0.82% | |
| Barrow Hanley Mewhinney & Strauss Llc | 0.28% | 2,272,949 | $92,099,893 | $92,872,696 | +$772,803 | +0.84% | |
| Neuberger Berman Group Llc | 0.06% | 3,335,121 | $80,142,958 | $136,273,044 | +$56,130,086 | +70.04% | |
| Greenhouse Funds Lllp | 4.05% | 1,896,343 | $76,839,818 | $77,484,575 | +$644,757 | +0.84% | |
| Van Eck Associates Corp | 0.05% | 1,849,926 | $74,959,002 | $75,587,976 | +$628,974 | +0.84% | |
| Reinhart Partners, Llc. | 1.75% | 1,650,476 | $72,010,268 | $67,438,449 | -$4,571,819 | -6.35% | |
| Loomis Sayles & Co L P | 0.08% | 1,606,095 | $65,078,970 | $65,625,042 | +$546,072 | +0.84% | |
| Northern Trust Corp | 0.01% | 1,371,471 | $55,572,005 | $56,038,305 | +$466,300 | +0.84% | |
| Charles Schwab Investment Management Inc | 0.01% | 1,339,591 | $54,280,227 | $54,735,688 | +$455,461 | +0.84% | |
| Nomura Asset Management International Inc. | 0.08% | 1,330,080 | $53,895,000 | $54,347,069 | +$452,069 | +0.84% | |
| Price T Rowe Associates Inc | 0.01% | 1,320,910 | $53,524,000 | $53,972,383 | +$448,383 | +0.84% | |
| Morgan Stanley | 0.00% | 1,207,487 | $48,927,432 | $49,337,919 | +$410,487 | +0.84% | |
| Bank Of New York Mellon Corp | 0.01% | 1,126,793 | $45,657,643 | $46,040,762 | +$383,119 | +0.84% | |
| Goldman Sachs Group Inc | 0.00% | 1,076,557 | $43,622,089 | $43,988,119 | +$366,030 | +0.84% | |
| Royal Bank Of Canada | 0.01% | 932,192 | $37,772,000 | $38,089,365 | +$317,365 | +0.84% | |
| Ranger Investment Management, L.P. | 1.99% | 777,643 | $31,510,094 | $31,774,493 | +$264,399 | +0.84% | |
| Goehring & Rozencwajg Associates, Llc | 1.81% | 775,476 | $31,422,288 | $31,685,949 | +$263,661 | +0.84% | |
| Massachusetts Financial Services Co | 0.01% | 757,311 | $30,686,242 | $30,943,727 | +$257,485 | +0.84% | |
| Vanguard Fiduciary Trust Co | 0.01% | 711,899 | $28,846,147 | $29,088,193 | +$242,046 | +0.84% | |
| Old West Investment Management, Llc | 2.98% | 693,549 | $28,102,605 | $28,338,412 | +$235,807 | +0.84% | |
| Federated Hermes, Inc. | 0.04% | 666,525 | $27,007,593 | $27,234,212 | +$226,619 | +0.84% | |
| Principal Financial Group Inc | 0.01% | 606,803 | $26,474,814 | $24,793,971 | -$1,680,843 | -6.35% | |
| Invesco Ltd. | 0.00% | 638,880 | $25,887,418 | $26,104,637 | +$217,219 | +0.84% | |
| Fisher Asset Management, Llc | 0.01% | 635,141 | $25,735,912 | $25,951,861 | +$215,949 | +0.84% | |
| Jpmorgan Chase & Co | 0.00% | 500,375 | $19,963,954 | $20,445,323 | +$481,369 | +2.41% | |
| Boston Trust Walden Corp | 0.16% | 452,659 | $19,749,512 | $18,495,647 | -$1,253,865 | -6.35% | |
| Panagora Asset Management Inc | 0.06% | 485,013 | $19,652,727 | $19,817,631 | +$164,904 | +0.84% | |
| Aqr Capital Management Llc | 0.01% | 449,040 | $18,195,101 | $18,347,774 | +$152,673 | +0.84% | |
| First Trust Advisors Lp | 0.01% | 421,475 | $17,078,167 | $17,221,469 | +$143,302 | +0.84% | |
| Schroder Investment Management Group | 0.01% | 399,661 | $15,798,599 | $16,330,148 | +$531,549 | +3.36% | |
| Storebrand Asset Management As | 0.04% | 366,188 | $14,837,938 | $14,962,442 | +$124,504 | +0.84% | |
| Bank Of America Corp | 0.00% | 364,827 | $14,782,790 | $14,906,831 | +$124,041 | +0.84% | |
| Keating Investment Counselors Inc | 3.78% | 331,093 | $14,445,588 | $13,528,460 | -$917,128 | -6.35% | |
| Fmr Llc | 0.00% | 349,342 | $14,155,345 | $14,274,114 | +$118,769 | +0.84% | |
| Public Sector Pension Investment Board | 0.04% | 342,697 | $13,886,082 | $14,002,599 | +$116,517 | +0.84% | |
| Bessemer Group Inc | 0.02% | 331,212 | $13,420,000 | $13,533,322 | +$113,322 | +0.84% | |
| Granite Investment Partners, Llc | 0.68% | 328,414 | $13,307,335 | $13,418,996 | +$111,661 | +0.84% | |
| Sei Investments Co | 0.01% | 314,092 | $12,726,998 | $12,833,799 | +$106,801 | +0.84% | |
| Envestnet Asset Management Inc | 0.00% | 310,197 | $12,569,168 | $12,674,649 | +$105,481 | +0.84% | |
| Nuveen, Llc | 0.00% | 307,461 | $12,458,320 | $12,562,856 | +$104,536 | +0.84% | |
| Gamco Investors, Inc. Et Al | 0.11% | 303,898 | $12,313,947 | $12,417,272 | +$103,325 | +0.84% |
Frequently asked questions about OII
Who are the largest institutional holders of OII?
The largest institutional holders of OII reported in the latest SEC Form 13F filings include Blackrock, Inc., Vanguard Portfolio Management Llc, State Street Corp, Brown Advisory Inc, and Vanguard Capital Management Llc. InsiderSet ranks institutional holders by their latest reported OII position.
What is OII institutional ownership?
This page tracks OII positions reported by institutional investment managers through SEC Form 13F. OCEANEERING INTL INC (OII) institutional ownership on InsiderSet reflects disclosed 13F holdings among the managers we analyze, not every shareholder of the stock.
How many institutions own OII?
InsiderSet currently tracks 367 institutional managers reporting OII holdings in the latest available 13F data. This count reflects institutions included in the SEC Form 13F filings analyzed by InsiderSet and should not be interpreted as the total number of OII shareholders.
How much OII stock do institutions own?
Institutional investment managers disclosed approximately $4.06B in OII holdings for Q2 2026. This figure is reported 13F value as of the filing period, not necessarily today's market value.
When was OII institutional ownership last updated?
The latest OII institutional ownership data on InsiderSet is based on SEC Form 13F filings for the quarter ended June 30, 2026. Form 13F filings are generally reported after the quarter ends, so the holdings shown represent the latest publicly disclosed positions rather than real-time institutional holdings.
Are institutional OII holdings real-time?
No. Form 13F data is not real-time. It represents positions reported by institutional investment managers as of the end of the reporting quarter. An institution may have changed its OII position after the reporting date.
Are institutions buying or selling OII?
Institutional buying and selling can be analyzed by comparing OII positions across consecutive 13F reporting periods. InsiderSet's OII Ownership Changes page shows institutions that increased, reduced, initiated, or exited positions based on reported 13F holdings. View OII ownership changes.
How has OII institutional ownership changed over time?
InsiderSet tracks OII institutional holdings across multiple 13F reporting periods, allowing investors to compare institutional holder counts, reported value, and reported shares over time.