- Quarter end
- 31 Mar 2025
- the date the book describes
- Filed
- 15 May 2025
- latest of these filings; the earliest 2 May 2025
- Managers listing it
- 6
- at least, of 95 tracked, among listed positions
- Comparable managers
- 95
- filed both Q4 2024 and Q1 2025; 5 listed it in both
- Shares listed
- 4,138,303
- combined, among listed positions
- Reported value
- $152m
- combined, at the quarter end
Among the 95 comparable managers: 4 buyers (opened or added shares) and 2 sellers (trimmed or exited), at least, among listed positions. Their net change in shares is not known from listed positions, because at least one of them lists it in only one of the two quarters.
Managers listing ATMU in Q1 2025
6 of 6 holders
| Action | Filing | |||||
|---|---|---|---|---|---|---|
| D. E. Shaw & Co. | 2,077,535 | $76m | 0.07% | Added | +166,382 | 15 May 2025 (the filing on sec.gov) |
| MFS Investment Management | 1,221,363 | $45m | under 0.1% | Trimmed | -28,449 | 2 May 2025 (the filing on sec.gov) |
| Two Sigma Advisers LP | 480,598 | $18m | under 0.1% | Trimmed | -121,100 | 15 May 2025 (the filing on sec.gov) |
| Woodline Partners LP | 157,367 | $5.8m | under 0.1% | New | new | 15 May 2025 (the filing on sec.gov) |
| Quantbot Technologies LP | 101,086 | $3.7m | 0.12% | Added | +23,351 | 13 May 2025 (the filing on sec.gov) |
| PDT Partners LLC | 100,354 | $3.7m | 0.26% | Added | +25,613 | 15 May 2025 (the filing on sec.gov) |
Largest increases and reductions, by shares
Increases
- D. E. Shaw & Co.existing position · 2,077,535 shares now+166,382
- Woodline Partners LPnew position · 157,367 shares now+157,367
- PDT Partners LLCexisting position · 100,354 shares now+25,613
- Quantbot Technologies LPexisting position · 101,086 shares now+23,351
Reductions
- Two Sigma Advisers LPexisting position · 480,598 shares now-121,100
- MFS Investment Managementexisting position · 1,221,363 shares now-28,449
New positions and exits
New (1)
- Woodline Partners LP$5.8m
Exited (0)
No exit shown by a manager’s own filing.
Ownership over time
Tracked managers listing it, at least.
| Quarter | Holders | Reported value | Buyers | Sellers |
|---|---|---|---|---|
| Q2 2023 | 2 | $1.2m | n.a. | n.a. |
| Q4 2023 | 1 | $585k | 1 | 0 |
| Q1 2024 | 10 | $287m | 10 | 0 |
| Q2 2024 | 8 | $154m | 5 | 4 |
| Q3 2024 | 9 | $266m | 3 | 7 |
| Q4 2024 | 9 | $343m | 5 | 3 |
| Q1 2025 | 6 | $152m | 4 | 2 |
| Q2 2025 | 8 | $191m | 5 | 3 |
| Q3 2025 | 6 | $365m | 2 | 4 |
| Q4 2025 | 7 | $410m | 19 | 14 |
| Q1 2026 | 12 | $660m | 19 | 11 |
| Q2 2026 | 6 | $504m | 10 | 21 |
Compare with…
Holders over time, buyers and sellers, and the managers holding both, side by side for up to four stocks.
ATMU and AMZN →ATMU and TSLA →ATMU and HD →Choose a stock to compare with ATMU →
How much of the picture this is
A 13F is a manager’s long US-listed equity book at a quarter end, filed up to 45 days later. It shows no shorts, cash, bonds or performance, and it is never today’s portfolio. Large books are listed to their largest positions, so a manager missing from this table may still hold a small position below that line. These are 95 tracked managers, not the institutional market.
Which funds own ATMU, latest filings →Back to the 13F Explorer →