% 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 NUCLW 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 | Linden Advisors LP | 911,423911,423 | $1M | — | NEW |
| 2 | Walleye Capital LLC | 778,170778,170 | $1M | — | NEW |
| 3 | Arosa Capital Management LP | 750,000750,000 | $1M | — | NEW |
| 4 | ARISTEIA CAPITAL, L.L.C. | 630,711630,711 | $908,224 | — | NEW |
| 5 | LMR Partners LLP | 617,644617,644 | $858,525 | — | NEW |
| 6 | WHITEBOX ADVISORS LLC | 459,345459,345 | $638,490 | — | NEW |
| 7 | Saba Capital Management, L.P. | 349,998349,998 | $486,497 | — | NEW |
| 8 | Alberta Investment Management Corp | 300,000300,000 | $417,000 | — | NEW |
| 9 | MOORE CAPITAL MANAGEMENT, LP | 250,000250,000 | $347,500 | — | NEW |
| 10 | Hudson Bay Capital Management LP | 192,040192,040 | $288,060 | — | NEW |
| 11 | Q Global Advisors, LLC | 151,370151,370 | $210,000 | — | NEW |
| 12 | Shaolin Capital Management LLC | 125,000125,000 | $173,750 | — | NEW |
| 13 | D. E. Shaw & Co., Inc. | 87,88387,883 | $131,825 | — | NEW |
| 14 | AQR Arbitrage LLC | 81,47781,477 | $122,216 | — | NEW |
| 15 | DLD Asset Management, LP | 75,81175,811 | $105,377 | — | NEW |
| 16 | Caption Management, LLC | 72,25272,252 | $100,430 | — | NEW |
| 17 | Clear Street Group Inc. | 68,43768,437 | $95,127 | — | NEW |
| 18 | Mint Tower Capital Management B.V. | 10,00010,000 | $77,000 | — | NEW |
| 19 | Ionic Capital Management LLC | 40,82340,823 | $56,744 | — | NEW |
| 20 | GABELLI & Co INVESTMENT ADVISERS, INC. | 25,05025,050 | $34,820 | — | NEW |
| 21 | Bracebridge Capital, LLC | 25,00025,000 | $34,750 | — | NEW |
| 22 | GABELLI FUNDS LLC | 24,95024,950 | $34,681 | — | NEW |
| 23 | Wealthcare Advisory Partners LLC | 11,93811,938 | $16,594 | — | NEW |
| 24 | WOLVERINE ASSET MANAGEMENT LLC | 8,6208,620 | $11,982 | — | NEW |
| 25 | UBS Group AG | 3,3323,332 | $4,631 | — | NEW |
| 26 | OSAIC HOLDINGS, INC. | 350350 | $486 | — | NEW |
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 |
|---|---|---|---|---|---|---|---|
| Linden Advisors LP | — | — | — | — | — | 911K | $1M |
| Walleye Capital LLC | — | — | — | — | — | 778K | $1M |
| Arosa Capital Management LP | — | — | — | — | — | 750K | $1M |
| ARISTEIA CAPITAL, L.L.C. | — | — | — | — | — | 631K | $908,224 |
| LMR Partners LLP | — | — | — | — | — | 618K | $858,525 |
| WHITEBOX ADVISORS LLC | — | — | — | — | — | 459K | $638,490 |
| Saba Capital Management, L.P. | — | — | — | — | — | 350K | $486,497 |
| Alberta Investment Management Corp | — | — | — | — | — | 300K | $417,000 |
| MOORE CAPITAL MANAGEMENT, LP | — | — | — | — | — | 250K | $347,500 |
| Hudson Bay Capital Management LP | — | — | — | — | — | 192K | $288,060 |
| Q Global Advisors, LLC | — | — | — | — | — | 151K | $210,000 |
| Shaolin Capital Management LLC | — | — | — | — | — | 125K | $173,750 |
| D. E. Shaw & Co., Inc. | — | — | — | — | — | 88K | $131,825 |
| AQR Arbitrage LLC | — | — | — | — | — | 81K | $122,216 |
| DLD Asset Management, LP | — | — | — | — | — | 76K | $105,377 |
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.
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 | |
|---|---|---|---|
| Linden Advisors LP | +911,423 | $1M | OPEN |
| Walleye Capital LLC | +778,170 | $1M | OPEN |
| Arosa Capital Management LP | +750,000 | $1M | OPEN |
| ARISTEIA CAPITAL, L.L.C. | +630,711 | $876,688 | OPEN |
| LMR Partners LLP | +617,644 | $858,525 | OPEN |
| Biggest sellers | Δ shares | Δ value | |
|---|---|---|---|
| No filer reduced its position this quarter. | |||
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).
