RADNET INC RDNT
COM · Common Stock · CUSIP 750491102 · ISIN US7504911022
- SectorHealth care
- IndustryServices-Medical Laboratories
- HeadquartersLos Angeles, CA
- Websiteradnet.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($4.7m this quarter). Holder counts are more reliable. Shares outstanding: 77.6m as of 2026-02-27, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $55.90. Options: 6 managers hold calls ($8.0m notional), 8 hold puts ($2.5m).
Trends to Q1 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 154 |
| Q4 2022 | 146 |
| Q1 2023 | 153 |
| Q2 2023 | 187 |
| Q3 2023 | 192 |
| Q4 2023 | 215 |
| Q1 2024 | 278 |
| Q2 2024 | 279 |
| Q3 2024 | 305 |
| Q4 2024 | 332 |
| Q1 2025 | 309 |
| Q2 2025 | 330 |
| Q3 2025 | 329 |
| Q4 2025 | 343 |
| Q1 2026 | 341 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q2 2024 | 142 | 141 |
| Q3 2024 | 154 | 125 |
| Q4 2024 | 159 | 137 |
| Q1 2025 | 164 | 167 |
| Q2 2025 | 199 | 112 |
| Q3 2025 | 185 | 134 |
| Q4 2025 | 163 | 146 |
| Q1 2026 | 179 | 150 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q2 2025 | $2.2m | $1.1m | 0.52 |
| Q3 2025 | $6.1m | $5.8m | 0.95 |
| Q4 2025 | $46.9m | $55.9m | 1.19 |
| Q1 2026 | $8.0m | $2.5m | 0.32 |
Biggest buyers
| PRICE T ROWE ASSOCIATES INC /MD/ | Added | +1.5m |
| Van Berkom & Associates Inc. | Added | +1.2m |
| Point72 Asset Management, L.P. | Added | +597.8k |
| RTW INVESTMENTS, LP | Added | +346.5k |
| Freestone Grove Partners LP | Added | +184.4k |
| UBS Group AG | Added | +171.2k |
| Global Alpha Capital Management Ltd. | Added | +170.0k |
| Clearbridge Investments, LLC | Added | +163.6k |
| Alyeska Investment Group, L.P. | Added | +157.0k |
| PALISADE CAPITAL MANAGEMENT, LP | Added | +130.2k |
Biggest sellers
| T. Rowe Price Investment Management, Inc. | Sold out | -891.8k |
| FULLER & THALER ASSET MANAGEMENT, INC. | Reduced | -730.6k |
| ADAGE CAPITAL PARTNERS GP, L.L.C. | Sold out | -476.6k |
| MILLENNIUM MANAGEMENT LLC | Reduced | -334.4k |
| AMERIPRISE FINANCIAL INC | Reduced | -221.0k |
| FRED ALGER MANAGEMENT, LLC | Reduced | -205.9k |
| Integral Health Asset Management, LLC | Sold out | -200.0k |
| JANE STREET GROUP, LLC | Sold out | -196.0k |
| Allspring Global Investments Holdings, LLC | Reduced | -182.9k |
| Balyasny Asset Management L.P. | Reduced | -160.0k |
Biggest calls
| Caption Management, LLC | New | $4.1m72.9k shares |
| CITADEL ADVISORS LLC | Reduced | $2.0m34.9k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $1.4m25.2k shares |
| JANE STREET GROUP, LLC | Reduced | $273.9k4.9k shares |
| IMC-Chicago, LLC | Reduced | $251.5k4.5k shares |
| SIMPLEX TRADING, LLC | Reduced | $5.6k100 shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $1.3m22.8k shares |
| JANE STREET GROUP, LLC | Reduced | $525.4k9.4k shares |
| IMC-Chicago, LLC | Reduced | $385.6k6.9k shares |
| HRT FINANCIAL LP | New | $212.0k3.8k shares |
| Twin Tree Management, LP | New | $72.7k1.3k shares |
| GROUP ONE TRADING LLC | Reduced | $33.5k600 shares |
| Walleye Capital LLC | Reduced | $11.2k200 shares |
| SIMPLEX TRADING, LLC | Reduced | $5.6k100 shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| BlackRock, Inc. 13G · institution filed 2025-10-17 | 12.0% |
| RTW INVESTMENTS, LP 13G · institution +1.1 pts · filed 2026-08-14 | 6.2% |
| PRICE T ROWE ASSOCIATES INC /MD/ 13G · institution new · filed 2026-05-15 | 5.4% |
| VANGUARD PORTFOLIO MANAGEMENT LLC 13G · institution new · filed 2026-04-29 | 5.1% |
Fell to 5% or below in the last year: VANGUARD GROUP INC (0.0%, 2026-03-27; now reported by VANGUARD PORTFOLIO MANAGEMENT LLC)
Insider purchases and sales in Q1 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q2 2024 | 0 | — | 11 | $17.4m | — |
| Q3 2024 | 0 | — | 1 | $941.7k | — |
| Q4 2024 | 0 | — | 2 | $4.1m | — |
| Q1 2025 | 0 | — | 3 | $2.3m | — |
| Q2 2025 | 0 | — | 5 | $8.3m | — |
| Q3 2025 | 0 | — | 5 | $10.5m | — |
| Q4 2025 | 0 | — | 2 | $7.4m | — |
| Q1 2026 | 0 | — | 1 | $1.9m | — |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-03-19 | Sorensen Alma Gregory Chief Strategy Officer, director | Sold | $933.0k15.0k shares |
| 2026-03-18 | Sorensen Alma Gregory Chief Strategy Officer, director | Sold | $932.3k15.0k shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q1 2026
| Manager | Shares | Change |
|---|---|---|
| BlackRock, Inc. 0.01% of their portfolio | 10.0m $560.9m | Added +14.7k |
| RTW INVESTMENTS, LP 2.38% of their portfolio | 4.3m $239.5m | Added +346.5k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.03% of their portfolio | 4.2m $232.2m | Added +1.5m |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.01% of their portfolio | 3.9m $217.9m | First filing |
| BECK MACK & OLIVER LLC 3.65% of their portfolio | 3.2m $177.0m | Reduced -65.3k |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 3.1m $173.9m | First filing |
| STATE STREET CORP 0.01% of their portfolio | 2.7m $148.2m | Added +72.5k |
| Van Berkom & Associates Inc. 1.88% of their portfolio | 2.1m $115.0m | Added +1.2m |
| GEODE CAPITAL MANAGEMENT, LLC 0.01% of their portfolio | 1.7m $96.4m | Added +52.1k |
| Invesco Ltd. 0.01% of their portfolio | 1.6m $91.3m | Added +36.7k |
| JB CAPITAL PARTNERS LP 13.79% of their portfolio | 1.4m $79.6m | Unchanged |
| Hood River Capital Management LLC 0.79% of their portfolio | 1.4m $78.9m | Added +15.6k |
| DIMENSIONAL FUND ADVISORS LP 0.02% of their portfolio | 1.4m $77.1m | Added +19.2k |
| Alyeska Investment Group, L.P. 0.21% of their portfolio | 1.3m $73.2m | Added +157.0k |
| Clearbridge Investments, LLC 0.06% of their portfolio | 1.3m $71.5m | Added +163.6k |
| GOLDMAN SACHS GROUP INC 0.01% of their portfolio | 1.2m $66.5m | Added +70.2k |
| PRINCIPAL FINANCIAL GROUP INC 0.03% of their portfolio | 1.1m $62.1m | Reduced -21.8k |
| AMERICAN CENTURY COMPANIES INC 0.03% of their portfolio | 902.2k $50.4m | Reduced -5.8k |
| AMERIPRISE FINANCIAL INC 0.01% of their portfolio | 899.1k $50.2m | Reduced -221.0k |
| Allspring Global Investments Holdings, LLC 0.08% of their portfolio | 865.4k $47.9m | Reduced -182.9k |
| Point72 Asset Management, L.P. 0.08% of their portfolio | 855.4k $47.8m | Added +597.8k |
| MORGAN STANLEY 0.00% of their portfolio | 850.5k $47.5m | Reduced -99.5k |
| BAMCO INC /NY/ 0.14% of their portfolio | 810.1k $45.3m | Unchanged |
| FULLER & THALER ASSET MANAGEMENT, INC. 0.15% of their portfolio | 806.3k $45.1m | Reduced -730.6k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.01% of their portfolio | 767.5k $42.9m | Added +9.2k |
| NORTHERN TRUST CORP 0.01% of their portfolio | 746.8k $41.7m | Added +17.3k |
| Polar Capital Holdings Plc 0.18% of their portfolio | 734.3k $41.0m | Added +76.2k |
| Rockefeller Capital Management L.P. 0.07% of their portfolio | 703.1k $39.3m | Added +70.8k |
| LOOMIS SAYLES & CO L P 0.05% of their portfolio | 686.2k $38.4m | Reduced -57.3k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.01% of their portfolio | 673.2k $37.6m | Reduced -16.0k |
| Nuveen, LLC 0.01% of their portfolio | 661.3k $37.0m | Reduced -37.1k |
| Global Alpha Capital Management Ltd. 2.21% of their portfolio | 658.2k $36.8m | Added +170.0k |
| PUNCH & ASSOCIATES INVESTMENT MANAGEMENT, INC. 1.92% of their portfolio | 595.3k $33.3m | Reduced -55.9k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 589.6k $33.0m | Added +77.2k |
| BESSEMER GROUP INC 0.05% of their portfolio | 550.2k $30.7m | Added +56.2k |
| Penserra Capital Management LLC 0.36% of their portfolio | 545.5k $30.5m | Added +27.7k |
| Defiance ETFs, LLC 0.44% of their portfolio | 545.5k $30.5m | Added +27.7k |
| WESTFIELD CAPITAL MANAGEMENT CO LP 0.12% of their portfolio | 531.9k $29.7m | Added +132 |
| NEUBERGER BERMAN GROUP LLC 0.02% of their portfolio | 503.2k $28.1m | Reduced -85.8k |
| UBS Group AG 0.00% of their portfolio | 486.7k $27.2m | Added +171.2k |
| DEUTSCHE BANK AG\ 0.01% of their portfolio | 482.4k $27.0m | Added +6.3k |
| Alpha Wave Global, LP 3.38% of their portfolio | 478.3k $26.7m | Reduced -63.1k |
| VANGUARD FIDUCIARY TRUST CO 0.01% of their portfolio | 476.5k $26.6m | First filing |
| ROYAL BANK OF CANADA 0.00% of their portfolio | 468.3k $26.2m | Reduced -6.1k |
| FRANKLIN RESOURCES INC 0.01% of their portfolio | 458.6k $25.6m | Reduced -97.7k |
| Tidal Investments LLC 0.08% of their portfolio | 442.1k $24.7m | Added +42.0k |
| SOROS FUND MANAGEMENT LLC 0.34% of their portfolio | 438.4k $24.5m | Reduced -136.1k |
| RAYMOND JAMES FINANCIAL INC 0.01% of their portfolio | 423.7k $23.7m | Added +30.2k |
| VOYA INVESTMENT MANAGEMENT LLC 0.02% of their portfolio | 417.4k $23.3m | Added +76.6k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 410.3k $22.9m | Reduced -12.5k |
| WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio | 395.9k $22.1m | Reduced -10.0k |
| EMERALD ADVISERS, LLC 0.68% of their portfolio | 381.8k $21.3m | Reduced -13.0k |
| SILVERCREST ASSET MANAGEMENT GROUP LLC 0.15% of their portfolio | 381.5k $21.3m | Added +46.2k |
| Freestone Grove Partners LP 0.15% of their portfolio | 365.4k $20.4m | Added +184.4k |
| JENNISON ASSOCIATES LLC 0.01% of their portfolio | 355.1k $19.8m | Added +4.5k |
| FRED ALGER MANAGEMENT, LLC 0.08% of their portfolio | 341.9k $19.1m | Reduced -205.9k |
| PICTON MAHONEY ASSET MANAGEMENT 0.18% of their portfolio | 309.1k $17.3m | Added +91.5k |
| SEGALL BRYANT & HAMILL, LLC 0.24% of their portfolio | 301.8k $16.9m | Reduced -15.7k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.02% of their portfolio | 298.8k $16.7m | Added +51.1k |
| PALISADE CAPITAL MANAGEMENT, LP 0.54% of their portfolio | 291.3k $16.3m | Added +130.2k |
| Penn Capital Management Company, LLC 1.20% of their portfolio | 276.8k $15.5m | Added +2.4k |
| WCM INVESTMENT MANAGEMENT, LLC 0.03% of their portfolio | 257.4k $14.3m | Reduced -10.8k |
| SEI INVESTMENTS CO 0.01% of their portfolio | 255.0k $14.3m | Reduced -14.3k |
| EMERALD MUTUAL FUND ADVISERS TRUST 0.68% of their portfolio | 250.6k $14.0m | Reduced -649 |
| Public Sector Pension Investment Board 0.04% of their portfolio | 249.2k $13.9m | Added +9.0k |
| WHITTIER TRUST CO 0.15% of their portfolio | 241.5k $13.3m | Added +22.2k |
| FMR LLC 0.00% of their portfolio | 222.4k $12.4m | Added +412 |
| AGF MANAGEMENT LTD 0.05% of their portfolio | 187.4k $10.5m | Added +28.4k |
| RHUMBLINE ADVISERS 0.01% of their portfolio | 186.6k $10.4m | Added +4.6k |
| Legal & General Group Plc 0.00% of their portfolio | 158.0k $8.8m | Reduced -13.1k |
| Thrivent Financial for Lutherans 0.02% of their portfolio | 141.5k $7.9m | Added +93.8k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 137.2k $7.6m | Added +61.3k |
| ROYCE & ASSOCIATES LP 0.08% of their portfolio | 137.0k $7.7m | Added +23.4k |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.01% of their portfolio | 136.6k $7.6m | Added +44.8k |
| MAIRS & POWER INC 0.08% of their portfolio | 133.1k $7.4m | Added +37.5k |
| Swiss National Bank 0.00% of their portfolio | 129.9k $7.3m | Added +900 |
| Cerity Partners LLC 0.01% of their portfolio | 123.5k $6.9m | Reduced -23.9k |
| WHITTIER TRUST CO OF NEVADA INC 0.14% of their portfolio | 121.2k $6.7m | Added +4.3k |
| ROBOTTI ROBERT 1.05% of their portfolio | 120.5k $6.7m | Reduced -63.6k |
| Holocene Advisors, LP 0.02% of their portfolio | 120.2k $6.7m | New |
| Pier Capital, LLC 1.10% of their portfolio | 118.9k $6.6m | Reduced -2.1k |
| BNP PARIBAS FINANCIAL MARKETS 0.00% of their portfolio | 115.6k $6.5m | Reduced -921 |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 113.1k $8.1m | Reduced -51.3k |
| Sequoia Financial Advisors, LLC 0.04% of their portfolio | 113.0k $6.3m | Reduced -682 |
| HARBOR CAPITAL ADVISORS, INC. 0.48% of their portfolio | 105.2k $5.9m | Reduced -8.6k |
| Granahan Investment Management, LLC 0.28% of their portfolio | 104.3k $5.8m | New |
| ENVESTNET ASSET MANAGEMENT INC 0.00% of their portfolio | 102.8k $5.7m | Reduced -4.7k |
| First Eagle Investment Management, LLC 0.01% of their portfolio | 94.1k $5.3m | Added +1.0k |
| CITIGROUP INC 0.00% of their portfolio | 89.7k $5.0m | Reduced -27.2k |
| Rathbones Group PLC 0.01% of their portfolio | 82.7k $4.6m | Unchanged |
| Caisse de depot et placement du Quebec 0.01% of their portfolio | 82.6k $4.6m | New |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 77.6k $4.3m | Added +15.7k |
| SEB Asset Management AB 0.02% of their portfolio | 76.7k $4.3m | First filing |
| STATE OF WISCONSIN INVESTMENT BOARD 0.01% of their portfolio | 76.6k $4.3m | Reduced -4.1k |
| Hilton Capital Management, LLC 0.31% of their portfolio | 74.6k $4.2m | Added +9.6k |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 71.3k $4.0m | Added +6.7k |
| WHITE PINE CAPITAL LLC 0.54% of their portfolio | 69.4k $3.9m | Added +32.2k |
| D.A. DAVIDSON & CO. 0.02% of their portfolio | 65.6k $3.7m | Unchanged |
| FIRST TRUST ADVISORS LP 0.00% of their portfolio | 65.3k $3.6m | Reduced -28.1k |
| VANGUARD ASSET MANAGEMENT, Ltd 0.00% of their portfolio | 62.1k $3.5m | First filing |