Institutional HoldersBeta
Who holds a company, from every 13F filed for the quarter, one row per filer exactly as filed, against the latest share count the company reported.
Share classes (cover page of the 20-F filed 2026-04-03, as of 2025-12-31)
| Class | Listed | Shares outstanding | Held by 13F filers | % of class | Holders | CUSIP |
|---|---|---|---|---|---|---|
| Common stock | MDXH · NASDAQ | 51,364,520 | 16,598,839 | 32.3% | 26 | B5950S113 |
Each class is compared with its own share count; classes are not added together. A class that is not exchange-listed cannot be held by 13F filers.
Top holders (26 of 26 · B5950S113)
change vs 2026-03-31| # | Filer | Shares | % of class | Value | Change |
|---|---|---|---|---|---|
| 1 | Bleichroeder LP | 7,378,333 | 14.36% | $3.0M | — |
| 2 | MVM Partners, LLC | 4,700,457 | 9.15% | $1.9M | — |
| 3 | PERKINS CAPITAL MANAGEMENT INC | 1,411,891 | 2.75% | $580K | -64,550 (-4.4%) |
| 4 | CITADEL ADVISORS LLC | 509,674 | 0.99% | $209K | +450,040 (+754.7%) |
| 5 | JANE STREET GROUP, LLC | 503,219 | 0.98% | $207K | NEW |
| 6 | GSA CAPITAL PARTNERS LLP | 481,985 | 0.94% | $198K | +470,893 (+4245.3%) |
| 7 | RENAISSANCE TECHNOLOGIES LLC | 325,084 | 0.63% | $133K | +20,384 (+6.7%) |
| 8 | MILLENNIUM MANAGEMENT LLC | 228,510 | 0.44% | $94K | -316,218 (-58.1%) |
| 9 | Squarepoint Ops LLC | 200,281 | 0.39% | $82K | NEW |
| 10 | XTX Topco Ltd | 195,039 | 0.38% | $80K | +157,324 (+417.1%) |
| 11 | HRT FINANCIAL LP | 184,477 | 0.36% | $75K | +173,154 (+1529.2%) |
| 12 | BlackRock, Inc. | 147,063 | 0.29% | $60K | +42,742 (+41.0%) |
| 13 | Virtu Financial LLC | 134,178 | 0.26% | $55K | NEW |
| 14 | Ground Swell Capital, LLC | 88,114 | 0.17% | $36K | NEW |
| 15 | Tower Research Capital LLC (TRC) | 36,549 | 0.07% | $15K | NEW |
| 16 | FAS Wealth Partners, Inc. | 22,625 | 0.04% | $9K | — |
| 17 | Lido Advisors, LLC | 20,253 | 0.04% | $8K | +9,756 (+92.9%) |
| 18 | Cambridge Investment Research Advisors, Inc. | 20,000 | 0.04% | $8K | +10,000 (+100.0%) |
| 19 | Intesa Sanpaolo Wealth Management | 10,000 | 0.02% | $4K | — |
| 20 | MORGAN STANLEY | 764 | 0.00% | $313 | -15,620 (-95.3%) |
| 21 | WELLS FARGO & COMPANY/MN | 200 | 0.00% | $82 | — |
| 22 | Monetary Solutions, Ltd | 85 | 0.00% | $35 | — |
| 23 | SBI Securities Co., Ltd. | 29 | 0.00% | $12 | — |
| 24 | BARCLAYS PLC | 16 | 0.00% | $7 | -678 (-97.7%) |
| 25 | Farther Finance Advisors, LLC | 10 | 0.00% | $4 | — |
| 26 | UBS Group AG | 3 | 0.00% | $1 | -173 (-98.3%) |
Exited since 2026-03-31 (30 filers; largest 25 shown)
| AWM Investment Company, Inc. | −5,221,282 |
| Samjo Management, LLC | −1,449,450 |
| Mink Brook Asset Management LLC | −1,203,454 |
| NORTHERN TRUST CORP | −494,523 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | −267,692 |
| Panoramic Capital, LLC | −238,668 |
| KENNEDY CAPITAL MANAGEMENT LLC | −205,438 |
| LANDSCAPE CAPITAL MANAGEMENT, L.L.C. | −163,655 |
| Shay Capital LLC | −150,000 |
| GOLDMAN SACHS GROUP INC | −98,619 |
| 683 Capital Management, LLC | −97,000 |
| Russell Investments Group, Ltd. | −68,871 |
| Hudson Bay Capital Management LP | −62,497 |
| MARSHALL WACE, LLP | −50,166 |
| BANK OF AMERICA CORP /DE/ | −43,492 |
| AlphaCentric Advisors LLC | −32,951 |
| GEODE CAPITAL MANAGEMENT, LLC | −29,185 |
| Catalyst Funds Management Pty Ltd | −28,046 |
| FIRST MANHATTAN CO. LLC. | −27,000 |
| TWO SIGMA INVESTMENTS, LP | −21,184 |
| Point72 Asset Management, L.P. | −20,767 |
| CITIGROUP INC | −18,945 |
| AXQ CAPITAL, LP | −15,954 |
| Diametric Capital, LP | −13,203 |
| OMERS ADMINISTRATION Corp | −11,800 |
Large holders from 13D/13G (latest per reporting person, last 2 years)
Filed when a holder crosses 5% or changes materially, so often more current than the quarter-end 13F. Percentages are the filer's own, against the share count they used.
| Reporting person | Form | Filed | Event | Shares | % of class |
|---|---|---|---|---|---|
| Laurence W. Lytton | SCHEDULE 13G/A | 2026-08-17 | 2026-08-13 | 18,558,988 | 19.5% |
| Lytton-Kambara Foundation | SCHEDULE 13G/A | 2026-08-17 | 2026-08-13 | 11,583,098 | 12.1% |
| Andrew Gundlach | SCHEDULE 13D | 2026-08-14 | 2026-08-11 | 31,648,563 | 33.2% |
| Bleichroeder Holdings LLC | SCHEDULE 13D | 2026-08-14 | 2026-08-11 | 31,648,563 | 33.2% |
| Bleichroeder LP | SCHEDULE 13D | 2026-08-14 | 2026-08-11 | 31,648,563 | 33.2% |
| LYTTON LAURENCE W | SCHEDULE 13G/A | 2026-08-13 | 2026-06-30 | 4,943,464 | 9.6% |
| AWM Investment Company, Inc. | SCHEDULE 13G/A | 2026-07-08 | 2026-06-30 | 0 | 0% |
| Exact Sciences Corporation | SCHEDULE 13G/A | 2026-01-16 | 2026-01-09 | 6,441,171 | 12% |
| Genomic Health, Inc. | SCHEDULE 13G/A | 2026-01-16 | 2026-01-09 | 6,441,171 | 12% |
Source: SEC Form 13F-HR information tables for the quarter ending 2026-06-30 (filed within 45 days of quarter end; amendments applied; values normalised to dollars), the share count from the company's latest 10-K/10-Q XBRL cover page, and Schedule 13D/13G filings. Each row is a legal 13F filer as filed — related entities (e.g. Vanguard's advisers) are not merged. Retail brokerage accounts are not reported on 13F, so the remainder is mostly retail and insiders.