RMBS in the 13F filings
Rambus Inc Del · CUSIP 750917106
- Quarter end
- 30 Jun 2026
- the date the book describes
- Filed
- 27 Oct 2026
- latest of these filings; the earliest 3 Aug 2026
- Managers listing it
- 26
- at least, of 95 tracked, among listed positions
- Comparable managers
- 91
- filed both Q1 2026 and Q2 2026; 6 listed it in both
- Shares listed
- 26,715,794
- combined, among listed positions
- Reported value
- $3.5bn
- combined, at the quarter end
1 line marked †. Value as filed implies a price far from other filers'. Each counts in holders and value as filed, and is left out of the net change in shares.
AllianceBernstein LP. Values in this filing are at the previous quarter end's prices; its share count is the quarter end's.
Among the 91 comparable managers: 17 buyers (opened or added shares) and 12 sellers (trimmed or exited), at least, among listed positions. Their net change in shares was +8,753,917.
Managers listing RMBS in Q2 2026
26 of 26 holders
Largest increases and reductions, by shares
Increases
- Fidelity (FMR LLC)existing position · 10,460,026 shares now+7,141,577
- D. E. Shaw & Co.existing position · 739,701 shares now+726,896
- Susquehanna International Group LLPexisting position · 555,935 shares now+470,111
- Citadel Advisors LLCexisting position · 400,151 shares now+383,656
- Millennium Management LLCexisting position · 472,818 shares now+331,504
Reductions
- Wellington Management Group LLPexisting position · 418,533 shares now-438,065
- AllianceBernstein LPexisting position · 155,136 shares now-112,053
- Man Group PLCexisting position · 38,613 shares now-100,519
- Janus Henderson Group Ltdexisting position · 288,553 shares now-70,339
- Bridgewater Associates LPexisting position · 3,871 shares now-47,983
New positions and exits
New (6)
Exited (3)
- Steadfast Capital Management LPwas $13m
- Holocene Advisors LPwas $4.3m
- Winton Group Ltdwas $262k
Ownership over time
Tracked managers listing it, at least.
| Quarter | Holders | Reported value | Buyers | Sellers |
|---|---|---|---|---|
| Q2 2013 | 1 | $33k | n.a. | n.a. |
| Q1 2014 | 2 | $7.1m | n.a. | n.a. |
| Q2 2014 | 2 | $19m | n.a. | n.a. |
| Q3 2014 | 1 | $14m | n.a. | n.a. |
| Q4 2014 | 1 | $242k | n.a. | n.a. |
| Q1 2015 | 1 | $5.0m | n.a. | n.a. |
| Q2 2015 | 3 | $65m | n.a. | n.a. |
| Q3 2015 | 4 | $61m | n.a. | n.a. |
| Q4 2015 | 2 | $64m | n.a. | n.a. |
| Q1 2016 | 3 | $76m | n.a. | n.a. |
| Q2 2016 | 1 | $44m | n.a. | n.a. |
| Q3 2016 | 3 | $47m | n.a. | n.a. |
| Q4 2016 | 1 | $49m | n.a. | n.a. |
| Q1 2017 | 1 | $48m | n.a. | n.a. |
| Q2 2017 | 3 | $44m | n.a. | n.a. |
| Q3 2017 | 3 | $95m | n.a. | n.a. |
| Q4 2017 | 3 | $109m | n.a. | n.a. |
| Q1 2018 | 5 | $106m | n.a. | n.a. |
| Q2 2018 | 3 | $95m | n.a. | n.a. |
| Q3 2018 | 1 | $1.2m | n.a. | n.a. |
| Q4 2018 | 2 | $1.2m | n.a. | n.a. |
| Q1 2019 | 3 | $2.7m | n.a. | n.a. |
| Q2 2019 | 4 | $90m | n.a. | n.a. |
| Q3 2019 | 3 | $97m | n.a. | n.a. |
| Q4 2019 | 6 | $121m | n.a. | n.a. |
| Q1 2020 | 2 | $83m | n.a. | n.a. |
| Q2 2020 | 3 | $109m | n.a. | n.a. |
| Q3 2020 | 3 | $92m | n.a. | n.a. |
| Q4 2020 | 6 | $116m | n.a. | n.a. |
| Q1 2021 | 4 | $109m | n.a. | n.a. |
| Q2 2021 | 6 | $133m | n.a. | n.a. |
| Q3 2021 | 3 | $105m | n.a. | n.a. |
| Q4 2021 | 4 | $118m | n.a. | n.a. |
| Q1 2022 | 6 | $163m | n.a. | n.a. |
| Q2 2022 | 2 | $109m | n.a. | n.a. |
| Q3 2022 | 4 | $142m | n.a. | n.a. |
| Q4 2022 | 6 | $227m | n.a. | n.a. |
| Q1 2023 | 9 | $464m | n.a. | n.a. |
| Q2 2023 | 9 | $319m | n.a. | n.a. |
| Q3 2023 | 4 | $279m | n.a. | n.a. |
| Q4 2023 | 5 | $574m | 3 | 4 |
| Q1 2024 | 4 | $518m | 4 | 0 |
| Q2 2024 | 6 | $558m | 3 | 3 |
| Q3 2024 | 8 | $174m | 7 | 2 |
| Q4 2024 | 5 | $432m | 2 | 3 |
| Q1 2025 | 6 | $555m | 4 | 2 |
| Q2 2025 | 4 | $403m | 2 | 2 |
| Q3 2025 | 6 | $966m | 5 | 2 |
| Q4 2025 | 7 | $1.2bn | 19 | 8 |
| Q1 2026 | 8 | $1.1bn | 8 | 21 |
| Q2 2026 | 12 | $3.2bn | 17 | 12 |
Compare with…
Holders over time, buyers and sellers, and the managers holding both, side by side for up to four stocks.
RMBS and NVDA →RMBS and AVGO →RMBS and MU →Choose a stock to compare with RMBS →
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 RMBS, latest filings →Back to the 13F Explorer →