% of shares outstanding not shown: no SEC cover-page share count falls within 120 days of the 2026-Q1 quarter end, so any percentage would rest on a count that cannot speak for this quarter. Holder share counts are shown as filed.
Crowding percentile withheld — no market cap for RADX in the served universe — the cohort is size-matched, and an unmatched percentile would compare a micro-cap register to a mega-cap one.
| # | Holder | Shares | Value | % of shares out | Δ QoQ |
|---|---|---|---|---|---|
| 1 | SILVERARC CAPITAL MANAGEMENT, LLC | 187,406187,406 | $805,846 | — | — |
| 2 | Stonepine Capital Management, LLC | 51,000,00051.0M | $738,977 | — | — |
| 3 | HSBC HOLDINGS PLC | 61,37261,372 | $264,513 | — | TRIM -84% |
| 4 | Regal Partners Ltd | 40,13840,138 | $172,593 | — | TRIM -56% |
| 5 | PNC FINANCIAL SERVICES GROUP, INC. | 16,00016,000 | $68,800 | — | — |
| 6 | UBS Group AG | 3,0003,000 | $12,900 | — | TRIM -79% |
| 7 | RHUMBLINE ADVISERS | 121121 | $519 | — | ADD 1917% |
Rows rank by the value each filer reported — 13F filers price their own positions, so a holder with fewer shares can rank just above one with more.
| Holder | 2024-Q4 | 2025-Q1 | 2025-Q2 | 2025-Q3 | 2025-Q4 | 2026-Q1 | Latest value |
|---|---|---|---|---|---|---|---|
| SILVERARC CAPITAL MANAGEMENT, LLC | 187K | 187K | 187K | 187K | 187K | 187K | $805,846 |
| Stonepine Capital Management, LLC | — | — | — | — | 51.0M | 51.0M | $738,977 |
| HSBC HOLDINGS PLC | — | — | — | — | 383K | 61K | $264,513 |
| Regal Partners Ltd | 91K | 91K | 91K | 91K | 91K | 40K | $172,593 |
| PNC FINANCIAL SERVICES GROUP, INC. | — | — | 8K | 16K | 16K | 16K | $68,800 |
| UBS Group AG | 1K | — | 18K | 18K | 14K | 3K | $12,900 |
| RHUMBLINE ADVISERS | — | — | — | — | 6 | 121 | $519 |
Shares reported each quarter by the largest current holders. Green = added vs the prior filing, red = trimmed, grey = roughly held; a dash is a quarter with no 13F on file (a gap is skipped, not read as an exit). 13F is filed up to 45 days after quarter-end. Up to 40 quarters (10 years) available — use the selector above.
Holder count only — too few computable %-of-shares-outstanding quarters for a % pane. Line breaks are quarters with no 13F record, never interpolated.
| Quarter | Holders | Shares held | % shares out | Value held |
|---|---|---|---|---|
| 2026-Q1 | 7 | 51,308,037 | — | $2M |
| 2025-Q4 | 11 | 51,731,201 | — | $5M |
| 2025-Q3 | 4 | 312,506 | — | $2M |
| 2025-Q2 | 5 | 339,690 | — | $2M |
| 2025-Q1 | 3 | 342,915 | — | $2M |
| 2024-Q4 | 4 | 435,803 | — | $2M |
Short interest has its own tab now — open SI →
Source: SEC Form 13F — every institution manager (≥ $100M in 13F securities) reporting a long US-listed position, across ~10,250 filers over 10 years of history. 13F is long-only, US-listed, filed up to 45 days after quarter-end.
| Biggest buyers | Δ shares | Δ value | |
|---|---|---|---|
| RHUMBLINE ADVISERS | +115 | $495 | ADD |
| Biggest sellers | Δ shares | Δ value | |
|---|---|---|---|
| HSBC HOLDINGS PLC | −321,876 | $1M | TRIM |
| Regal Partners Ltd | −50,771 | $218,315 | TRIM |
| Virtu Financial LLC | −14,591 | $62,741 | CLOSE |
| JANE STREET GROUP, LLC | −14,469 | $62,217 | CLOSE |
| UBS Group AG | −11,277 | $48,491 | TRIM |
The 2025-Q4 register is as-filed in ITS OWN share basis; every count below was rebased into the 2026-Q1 basis (no split in between, factor 1). Dollar figures value the SHARE delta at one price — the 2026-03-31 close — rather than differencing two filings' own reported values, which would mix the quarter's price move into the trade figure.
13Fs disclose LONG US-listed positions only — shorts, most derivatives, bonds and non-US listings are invisible here, and a filer's quarter-over-quarter change is not necessarily a trade (index rebalances, in-kind transfers and entity successions all read as flow).
