OSI SYSTEMS INC (OSIS) Top Institutional Shareholders
OSI SYSTEMS INC (OSIS) is currently reported in institutional portfolios tracked by InsiderSet based on the latest available SEC Form 13F filings for the quarter ended March 31, 2026. The institutional investors covered on this page collectively reported approximately $4.77B in OSIS holdings during the latest filing period.
Blackrock, Inc. is currently the largest disclosed institutional shareholder of OSIS tracked by InsiderSet, reporting ownership valued at approximately $671.64M in its March 31, 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 $550.22M, representing an estimated loss of -18.08% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 56% of the total disclosed OSIS value among the investors covered in this analysis. Major shareholders include Blackrock, Inc., Fmr Llc, Vanguard Portfolio Management Llc, and several other long-term asset managers with concentrated positions in OSI SYSTEMS INC (OSIS).
This page ranks the largest institutional OSIS 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
361
Total Reported Value
$4.77B
Largest Holder
Blackrock, Inc.
Largest Position
$671.64M
Insider Transactions (90d)
0
Latest Filing Quarter
Q1 2026
New Institutional Positions
48
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% | 2,529,623 | $671,640,204 | $550,218,299 | -$121,421,905 | -18.08% | |
| Fmr Llc | 0.03% | 1,967,088 | $522,281,462 | $427,861,311 | -$94,420,151 | -18.08% | |
| Vanguard Portfolio Management Llc | 0.02% | 1,249,748 | $331,820,591 | $271,832,687 | -$59,987,904 | -18.08% | |
| Janus Henderson Group Plc | 0.10% | 772,314 | $205,056,005 | $167,986,018 | -$37,069,987 | -18.08% | |
| Vanguard Capital Management Llc | 0.00% | 699,253 | $185,658,664 | $152,094,520 | -$33,564,144 | -18.08% | |
| Mawer Investment Management Ltd. | 1.14% | 662,634 | $175,935,953 | $144,129,521 | -$31,806,432 | -18.08% | |
| State Street Corp | 0.01% | 662,141 | $175,805,057 | $144,022,289 | -$31,782,768 | -18.08% | |
| Capital International Investors | 0.04% | 619,479 | $164,477,869 | $134,742,877 | -$29,734,992 | -18.08% | |
| Geode Capital Management, Llc | 0.01% | 440,723 | $117,034,888 | $95,861,660 | -$21,173,228 | -18.09% | |
| Ubs Am, A Distinct Business Unit Of Ubs Asset Management Americas Llc | 0.02% | 430,561 | $114,318,251 | $93,651,323 | -$20,666,928 | -18.08% | |
| Dimensional Fund Advisors Lp | 0.02% | 395,428 | $104,992,115 | $86,009,544 | -$18,982,571 | -18.08% | |
| Invesco Ltd. | 0.02% | 373,274 | $99,107,978 | $81,190,828 | -$17,917,150 | -18.08% | |
| Hood River Capital Management Llc | 0.99% | 372,074 | $98,789,368 | $80,929,816 | -$17,859,552 | -18.08% | |
| Neuberger Berman Group Llc | 0.06% | 303,923 | $80,683,616 | $66,106,292 | -$14,577,324 | -18.07% | |
| Clark Capital Management Group, Inc. | 0.44% | 270,420 | $71,799,215 | $58,819,054 | -$12,980,161 | -18.08% | |
| Channing Capital Management, Llc | 1.81% | 266,884 | $70,860,371 | $58,049,939 | -$12,810,432 | -18.08% | |
| Bank Of America Corp | 0.01% | 266,375 | $70,725,226 | $57,939,226 | -$12,786,000 | -18.08% | |
| Primecap Management Co/Ca/ | 0.05% | 244,660 | $64,959,677 | $53,215,997 | -$11,743,680 | -18.08% | |
| Mirae Asset Global Etfs Holdings Ltd. | 0.08% | 232,497 | $61,598,225 | $50,570,422 | -$11,027,803 | -17.90% | |
| Systematic Financial Management Lp | 1.33% | 219,241 | $58,211,119 | $47,687,110 | -$10,524,009 | -18.08% | |
| Morgan Stanley | 0.00% | 210,377 | $55,857,567 | $45,759,101 | -$10,098,466 | -18.08% | |
| Charles Schwab Investment Management Inc | 0.01% | 200,986 | $53,363,793 | $43,716,465 | -$9,647,328 | -18.08% | |
| Loomis Sayles & Co L P | 0.07% | 191,467 | $50,836,404 | $41,645,987 | -$9,190,417 | -18.08% | |
| Neumeier Poma Investment Counsel Llc | 4.19% | 191,430 | $50,826,579 | $41,637,939 | -$9,188,640 | -18.08% | |
| William Blair Investment Management, Llc | 0.15% | 171,667 | $45,579,305 | $37,339,289 | -$8,240,016 | -18.08% | |
| Northern Trust Corp | 0.01% | 170,855 | $45,363,711 | $37,162,671 | -$8,201,040 | -18.08% | |
| Clearbridge Investments, Llc | 0.04% | 163,598 | $43,436,793 | $35,584,201 | -$7,852,592 | -18.08% | |
| Nomura Asset Management International Inc. | 0.07% | 161,492 | $42,878,000 | $35,126,125 | -$7,751,875 | -18.08% | |
| Ubs Group Ag | 0.01% | 135,961 | $36,099,005 | $29,572,877 | -$6,526,128 | -18.08% | |
| Driehaus Capital Management Llc | 0.23% | 117,963 | $31,320,356 | $25,658,132 | -$5,662,224 | -18.08% | |
| Swedbank Ab | 0.03% | 117,740 | $31,261,147 | $25,609,627 | -$5,651,520 | -18.08% | |
| Vanguard Fiduciary Trust Co | 0.01% | 107,652 | $28,582,683 | $23,415,387 | -$5,167,296 | -18.08% | |
| Oberweis Asset Management Inc/ | 0.84% | 106,593 | $28,301,507 | $23,185,043 | -$5,116,464 | -18.08% | |
| Principal Financial Group Inc | 0.01% | 102,417 | $27,192,737 | $22,276,722 | -$4,916,015 | -18.08% | |
| Envestnet Asset Management Inc | 0.01% | 100,377 | $26,651,120 | $21,833,001 | -$4,818,119 | -18.08% | |
| Bank Of New York Mellon Corp | 0.00% | 98,162 | $26,062,954 | $21,351,217 | -$4,711,737 | -18.08% | |
| Bnp Paribas Financial Markets | 0.02% | 97,909 | $25,995,819 | $21,296,187 | -$4,699,632 | -18.08% | |
| Ameriprise Financial Inc | 0.01% | 94,110 | $24,987,656 | $20,469,866 | -$4,517,790 | -18.08% | |
| Wellington Management Group Llp | 0.00% | 93,754 | $24,892,625 | $20,392,433 | -$4,500,192 | -18.08% | |
| Boston Partners | 0.02% | 86,529 | $23,024,124 | $18,820,923 | -$4,203,201 | -18.26% | |
| Asset Management One Co., Ltd. | 0.07% | 83,323 | $22,123,090 | $18,123,586 | -$3,999,504 | -18.08% | |
| Brown Advisory Inc | 0.03% | 78,254 | $20,777,166 | $17,021,028 | -$3,756,138 | -18.08% | |
| Goldman Sachs Group Inc | 0.00% | 75,120 | $19,945,112 | $16,339,351 | -$3,605,761 | -18.08% | |
| New York State Common Retirement Fund | 0.03% | 71,496 | $18,982,903 | $15,551,095 | -$3,431,808 | -18.08% | |
| Mirova | 0.70% | 65,007 | $17,260,009 | $14,139,673 | -$3,120,336 | -18.08% | |
| Nuveen, Llc | 0.00% | 59,840 | $15,888,119 | $13,015,798 | -$2,872,321 | -18.08% | |
| Public Sector Pension Investment Board | 0.05% | 55,384 | $14,705,006 | $12,046,574 | -$2,658,432 | -18.08% | |
| American Century Companies Inc | 0.01% | 50,994 | $13,539,417 | $11,091,705 | -$2,447,712 | -18.08% | |
| Wells Fargo & Company/Mn | 0.00% | 50,772 | $13,480,521 | $11,043,418 | -$2,437,103 | -18.08% | |
| Prospect Capital Advisors, Llc | 7.31% | 49,485 | $13,138,762 | $10,763,482 | -$2,375,280 | -18.08% |
Frequently asked questions about OSIS
Who owns the most OSIS stock?
The largest holders of OSIS are typically major institutional investors such as asset managers and hedge funds reporting on Form 13F. The table above ranks tracked superinvestors by reported position size using the latest available filings for OSI SYSTEMS INC (OSIS).
Is OSIS widely held by superinvestors?
Many widely followed stocks like OSIS appear across numerous superinvestor portfolios because of liquidity, index inclusion, and fundamentals. The holder count and table above show how broadly OSIS is represented among the institutional managers we track.
What do “Current Estimated Value”, “Gain/loss Since Filing”, and “Estimated Portfolio Performance” mean?
Current Estimated Value is reported share quantity from the latest 13F times our most recent split-adjusted U.S. session close. Gain/loss Since Filing is that estimate minus the reported 13F dollar value; Estimated Portfolio Performance is that difference as a percent of the reported value. Green means the estimate is above the filing value; red means below (not purchase cost). If many filers share the same implied filing price per share, the performance % may match across rows. These are not official fund marks or live quotes.