Comparable stake leader
BlackRock, Inc.
SEC ownership of RAMBUS INC
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0000917273.
Disclosed value leader
FMR LLC
Comparable rows
50/50
Latest evidence
03 Jun 2026
- Public ticker
- RMBS on Nasdaq
- Parsed ownership sources
- 13F, 13D/G, and 3/4/5
- Largest SEC-reported holder
- BlackRock, Inc.
- Latest 13D/G holder
- BlackRock, Inc.
- Latest parsed ownership date
- 03 Jun 2026
- Issuer CIK
- 0000917273
- Issuer location
- San Jose, CA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
2 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of RAMBUS INC (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
BlackRock, Inc.
Disclosed value leader
FMR LLC
Comparable rows
50/50
Latest evidence
03 Jun 2026
13F
13D/G
3/4/5
Lead comparable stake: 14%
13D/G row: BlackRock, Inc.
Showing 1-8 of 50 holder rows.
Quick read
BlackRock, Inc. leads the comparable SEC ownership view at 14%.
50 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens BlackRock, Inc.'s linked filing trail.
Comparable ownership
Top 5
BlackRock, Inc.
14%
FMR LLC
10%
VANGUARD PORTFOLIO MANAGEMENT LLC
6.2%
Invesco Ltd.
6%
VANGUARD CAPITAL MANAGEMENT LLC
5.2%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| BlackRock, Inc. |
13F
13D/G
Company
|
14%
from 13D/G
|
$1,402,745,519
16,305,306 shares
|
— | 31 Mar 2026 |
| FMR LLC |
13D/G
13F
Company
|
10%
|
$1,523,372,780
11,296,795 shares
|
$0 | 29 May 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC |
13D/G
13F
Vanguard Portfolio Management · Company
|
6.2%
|
$580,054,178
6,742,464 shares
|
$0 | 31 Mar 2026 |
| Invesco Ltd. |
13D/G
13F
Company
|
6%
|
$717,754,861
6,499,048 shares
|
$0 | 31 Mar 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC |
13D/G
13F
Vanguard Capital Management · Company
|
5.2%
|
$486,204,395
5,651,568 shares
|
$0 | 31 Mar 2026 |
| PRICE T ROWE ASSOCIATES INC /MD/ |
13D/G
13F
T. Rowe Price Associates, Inc. · Company
|
3.1%
|
$372,852,508
3,376,064 shares
|
-$221,933,487 | 31 Mar 2026 |
| Luc Seraphin |
3/4/5
President and CEO, Director
|
0.32%
|
$30,548,549
345,767 shares
|
-$4,406,884 | 01 Apr 2026 |
| Xianzhi Sean Fan |
3/4/5
EVP, COO
|
0.15%
|
$25,649,341
168,358 shares
|
-$5,751,226 | 26 May 2026 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Net insider flow leans to selling over the last 12 months. Net value: -$23,052,782.
Buys
$0
Insiders: 0
Sells
$23,052,782
Insiders: 9
Net
-$23,052,782
Shares: -196,512
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 196,512
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 96,730 | $0 | $13,664,678 | -$13,664,678 |
| 3-6 | 0 | 48,744 | $0 | $4,796,853 | -$4,796,853 |
| 6-9 | 0 | 35,301 | $0 | $3,420,796 | -$3,420,796 |
| 9-12 | 0 | 15,737 | $0 | $1,170,454 | -$1,170,454 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-17 of 17 reporting-owner rows connected to RAMBUS INC. Open a relationship link for the CIK-to-CIK filing trail.
Rows
17
Largest Forms 3/4/5 holder
James A. Mitarotonda
Net 12M change
-$23,052,782
Latest report
03 Jun 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| James A. Mitarotonda | Director | $36,096,419 | Mixed | 01 Apr 2022 | ||
| Luc Seraphin | President and CEO, Director | $30,548,549 | -$4,406,884 | -13% | Filing P/S | 01 Apr 2026 |
| Xianzhi Sean Fan | Evp, Coo | $25,649,341 | -$5,751,226 | -18% | Filing P/S | 26 May 2026 |
| Emiko Higashi | Director | $7,824,002 | -$2,559,757 | -25% | Filing P/S | 02 Jun 2026 |
| Desmond Lynch | Svp, Cfo | $6,459,135 | -$2,186,909 | -25% | Filing P/S | 23 Feb 2026 |
| Charles Kissner | Director | $5,448,341 | Mixed | 01 Apr 2026 | ||
| Keith A. Jones | Principal Accounting Officer | $3,630,502 | Mixed | 01 Mar 2022 | ||
| Sumeet Gagneja | Svp, Cfo | $3,554,759 | Median | 01 May 2026 | ||
| Sanjay Saraf | Director | $3,333,395 | Mixed | 01 Apr 2022 | ||
| Necip Sayiner | Director | $3,100,643 | -$3,323,312 | -52% | Filing P/S | 03 Jun 2026 |
| John Shinn | SVP, General Counsel | $3,032,316 | -$1,032,902 | -25% | Filing P/S | 22 May 2026 |
| Meera Rao | Director | $3,002,092 | -$1,736,618 | -37% | Filing P/S | 24 Apr 2026 |
| Eric B. Stang | Director | $2,997,072 | -$1,688,900 | -36% | Mixed | 01 Jun 2026 |
| John K. Allen | Chief Accounting Officer | $1,473,779 | Median | 03 Apr 2026 | ||
| Karen M. Rogge | Director | $1,152,068 | Mixed | 03 Apr 2023 | ||
| Steven Laub | Director | $943,781 | -$366,274 | -28% | Filing P/S | 07 May 2026 |
| Victor Peng | Director | $219,708 | Mixed | 01 Apr 2026 |
Recent insider transactions for RAMBUS INC
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Necip Sayiner | RMBS | Common Stock | Sale | -21.5% | $850,750 | $170.15 | -5,000 | 18,223 | 03 Jun 2026 | Direct |
| Emiko Higashi | RMBS | Common Stock | Sale | -16.8% | $1,605,000 | $160.50 | -10,000 | 49,519 | 02 Jun 2026 | Direct |
| Eric B. Stang | RMBS | Common Stock | Sale | -20.6% | $730,000 | $146.00 | -5,000 | 19,218 | 01 Jun 2026 | See Footnote |
| Emiko Higashi | RMBS | Common Stock | Sale | -7.75% | $787,850 | $157.57 | -5,000 | 59,519 | 26 May 2026 | Direct |
| Xianzhi Sean Fan | RMBS | Common Stock | Sale | -18.4% | $5,751,226 | $151.69 | -37,914 | 168,358 | 26 May 2026 | Direct |
| John Shinn | RMBS | Common Stock | Sale | -4.52% | $143,630 | $143.63 | -1,000 | 21,112 | 22 May 2026 | Direct |
| Necip Sayiner | RMBS | Common Stock | Sale | -29.7% | $1,278,888 | $130.18 | -9,824 | 23,223 | 08 May 2026 | Direct |
| Steven Laub | RMBS | Common Stock | Sale | -16.6% | $188,279 | $125.52 | -1,500 | 7,519 | 07 May 2026 | Direct |
| Sumeet Gagneja | RMBS | Common Stock | Award | 41,320 | 41,320 | 01 May 2026 | Direct | |||
| Meera Rao | RMBS | Common Stock | Sale | -13% | $446,692 | $150.30 | -2,972 | 19,974 | 24 Apr 2026 | Direct |
| Meera Rao | RMBS | Common Stock | Sale | -27.1% | $1,008,167 | $118.08 | -8,538 | 22,946 | 14 Apr 2026 | Direct |
| John K. Allen | RMBS | Common Stock | Tax liability | -6.19% | -1,131 | 17,131 | 03 Apr 2026 | Direct | ||
| Luc Seraphin | RMBS | Common Stock | Sale | -1.55% | $470,188 | $86.65 | -5,426 | 345,767 | 02 Apr 2026 | Direct |
| Emiko Higashi | RMBS | Common Stock | Award | 3.57% | 2,223 | 64,519 | 01 Apr 2026 | Direct | ||
| Steven Laub | RMBS | Common Stock | Award | 32.7% | 2,223 | 9,019 | 01 Apr 2026 | Direct | ||
| Meera Rao | RMBS | Common Stock | Award | 7.6% | 2,223 | 31,484 | 01 Apr 2026 | Direct | ||
| Necip Sayiner | RMBS | Common Stock | Award | 7.21% | 2,223 | 33,047 | 01 Apr 2026 | Direct | ||
| Eric B. Stang | RMBS | Common Stock | Award | 2,223 | 2,223 | 01 Apr 2026 | Direct | |||
| Victor Peng | RMBS | Common Stock | Award | 1323.2% | 2,223 | 2,391 | 01 Apr 2026 | Direct | ||
| Charles Kissner | RMBS | Common Stock | Award | 5.8% | 2,223 | 40,545 | 01 Apr 2026 | Direct | ||
| John Shinn | RMBS | Common Stock | Tax liability | -7.96% | -1,913 | 22,112 | 01 Apr 2026 | Direct | ||
| John Shinn | RMBS | Common Stock | Award | 30.1% | 5,558 | 24,025 | 01 Apr 2026 | Direct | ||
| Luc Seraphin | RMBS | Common Stock | Tax liability | -3.45% | -12,561 | 351,193 | 01 Apr 2026 | Direct | ||
| Luc Seraphin | RMBS | Common Stock | Award | 9.87% | 32,684 | 363,754 | 01 Apr 2026 | Direct | ||
| Xianzhi Sean Fan | RMBS | Common Stock | Tax liability | -4.59% | -9,916 | 206,272 | 01 Apr 2026 | Direct | ||
| Xianzhi Sean Fan | RMBS | Common Stock | Award | 11.5% | 22,234 | 216,188 | 01 Apr 2026 | Direct | ||
| John K. Allen | RMBS | Common Stock | Tax liability | -5.94% | -1,153 | 18,262 | 01 Apr 2026 | Direct | ||
| John K. Allen | RMBS | Common Stock | Award | 16.7% | 2,779 | 19,415 | 01 Apr 2026 | Direct | ||
| John Shinn | RMBS | Common Stock | Sale | -19.8% | $404,008 | $88.68 | -4,556 | 18,467 | 10 Mar 2026 | Direct |
| John Shinn | RMBS | Common Stock | Sale | -16.5% | $426,319 | $93.55 | -4,557 | 23,023 | 03 Mar 2026 | Direct |
| Luc Seraphin | RMBS | Common Stock | Sale | -10.8% | $3,936,696 | $98.63 | -39,914 | 331,070 | 02 Mar 2026 | Direct |
| Victor Peng | RMBS | Common Stock | Award | 168 | 168 | 02 Mar 2026 | Direct | |||
| Desmond Lynch | RMBS | Common Stock | Sale | -6.29% | $433,838 | $101.53 | -4,273 | 63,618 | 23 Feb 2026 | Direct |
| Desmond Lynch | RMBS | Common Stock | Tax liability | -24.6% | -22,105 | 67,891 | 01 Feb 2026 | Direct | ||
| Desmond Lynch | RMBS | Common Stock | Award | 62.3% | 34,554 | 89,996 | 01 Feb 2026 | Direct | ||
| John Shinn | RMBS | Common Stock | Tax liability | -26.4% | -9,884 | 27,580 | 01 Feb 2026 | Direct | ||
| John Shinn | RMBS | Common Stock | Award | 85.6% | 17,276 | 37,464 | 01 Feb 2026 | Direct | ||
| Xianzhi Sean Fan | RMBS | Common Stock | Tax liability | -32.3% | -92,403 | 193,954 | 01 Feb 2026 | Direct | ||
| Xianzhi Sean Fan | RMBS | Common Stock | Award | 108.2% | 148,802 | 286,357 | 01 Feb 2026 | Direct | ||
| Luc Seraphin | RMBS | Common Stock | Tax liability | -20% | -92,523 | 370,984 | 01 Feb 2026 | Direct | ||
| Luc Seraphin | RMBS | Common Stock | Award | 45% | 143,744 | 463,507 | 01 Feb 2026 | Direct | ||
| Xianzhi Sean Fan | RMBS | Common Stock | Gift | -0.22% | -300 | 137,555 | 21 Nov 2025 | Direct | ||
| Xianzhi Sean Fan | RMBS | Common Stock | Gift | -0.22% | -300 | 137,855 | 19 Nov 2025 | Direct | ||
| Eric B. Stang | RMBS | Common Stock | Sale | -16.4% | $447,140 | $111.78 | -4,000 | 20,394 | 10 Nov 2025 | See Footnote |
| Eric B. Stang | RMBS | Common Stock | Sale | -17% | $511,760 | $102.35 | -5,000 | 24,394 | 07 Nov 2025 | See Footnote |
| Desmond Lynch | RMBS | Common Stock | Sale | -14.1% | $920,973 | $101.50 | -9,074 | 55,356 | 06 Oct 2025 | Direct |
| Meera Rao | RMBS | Common Stock | Sale | -2.18% | $66,599 | $101.99 | -653 | 29,261 | 01 Oct 2025 | Direct |
| Desmond Lynch | RMBS | Common Stock | Sale | -12.3% | $832,098 | $91.70 | -9,074 | 64,430 | 15 Sep 2025 | Direct |
| Necip Sayiner | RMBS | Common Stock | Sale | -19.6% | $642,226 | $85.63 | -7,500 | 30,824 | 11 Sep 2025 | Direct |
| Meera Rao | RMBS | Common Stock | Sale | -9.11% | $215,160 | $71.72 | -3,000 | 29,914 | 02 Sep 2025 | Direct |
* marks a reported price that did not pass the local price check.