Rambus Inc.
IT ˙ BIT ˙ US7509171069
145,15 € ↑5,15 (3,68%)
2026-06-04
DEL PRIS
SecurityIT:1RMBS / Rambus Inc.
InstitutionFmr Llc
Latest Disclosed Ownership11,296,794 shares
Ownership 10.40%
Fmr Llc ownership in 1RMBS / Rambus Inc.

2026-06-05 - Fmr Llc has filed an SCHEDULE 13G form with the Securities and Exchange Commission (SEC) disclosing ownership of 11,296,794 shares of Rambus Inc. (IT:1RMBS). This represents 10.4 percent ownership of the company. In their previous filing dated 2017-02-14 , Fmr Llc had reported owning 4,273,800 shares, indicating an increase of 164.33 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File
Date		Effective
Date		Form Prev
Shares		 Latest
Shares		 ΔShares
(Percent)		 Ownership
(Percent)		 ΔOwnership
(Percent)
2026-06-05 2026-06-05 13G 4,273,800 11,296,794 164.33 10.40 168.80
2017-02-14 2017-02-14 13G/A 8,358,681 4,273,800 -48.87 3.87 -45.84
2016-02-12 2016-02-12 13G/A 8,358,681 7.14
2015-02-13 2015-02-13 13G/A 11,262,481 9.78
2014-02-14 2014-02-14 13G/A 11,788,381 10.42
2013-02-14 2013-02-14 13G/A 14,144,300 12.76
2012-02-14 2012-02-14 13G/A 14,892,500 13.54

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F RAMBUS INC DEL COM 750917106 3,318,449 1,731,420 109.10 285,486 95.76 0.0030
2026-02-17 2025-12-31 13F RAMBUS INC DEL COM 750917106 1,587,029 213,505 15.54 145,832 1.89 0.0074
2025-11-13 2025-09-30 13F RAMBUS INC DEL COM 750917106 1,373,524 1,035,263 306.05 143,121 560.91 0.0074
2025-08-14 2025-06-30 13F RAMBUS INC DEL COM 750917106 338,261 295,693 694.64 21,655 882.98 0.0012
2025-05-12 2025-03-31 13F RAMBUS INC DEL COM 750917106 42,568 -36,914 -46.44 2,204 -47.56 0.0001
2025-02-13 2024-12-31 13F RAMBUS INC DEL COM 750917106 79,482 16,752 26.70 4,201 58.65 0.0003
2024-11-13 2024-09-30 13F RAMBUS INC DEL COM 750917106 62,730 -667,598 -91.41 2,648 -93.83 0.0002
2024-08-13 2024-06-30 13F RAMBUS INC DEL COM 750917106 730,328 -182,890 -20.03 42,914 -23.97 0.0027
2024-05-13 2024-03-31 13F RAMBUS INC DEL COM 750917106 913,218 586,131 179.20 56,446 152.86 0.0038
2024-02-13 2023-12-31 13F RAMBUS INC DEL COM 750917106 327,087 13,835 4.42 22,324 27.74 0.0017
2023-11-13 2023-09-30 13F RAMBUS INC DEL COM 750917106 313,252 -238,812 -43.26 17,476 -50.67 0.0015
2023-08-11 2023-06-30 13F RAMBUS INC DEL COM 750917106 552,064 -162,450 -22.74 35,426 -3.28 0.0030
2023-08-11 2023-03-31 13F/A-1 RAMBUS INC DEL COM 750917106 714,514 709,541 14,267.87 36,626 20,475.84 0.0034
2023-05-11 2023-03-31 13F RAMBUS INC DEL COM 750917106 714,514 709,541 36,626 0.0007
2023-02-13 2022-12-31 13F RAMBUS INC DEL COM 750917106 4,973 -1,028 -17.13 178 17.11 0.0000
2022-11-10 2022-09-30 13F RAMBUS INC DEL COM 750917106 6,001 2,096 53.67 152 80.95 0.0000
2022-08-12 2022-06-30 13F RAMBUS INC DEL COM 750917106 3,905 184 4.94 84 -28.81 0.0000
2022-05-13 2022-03-31 13F RAMBUS INC DEL COM 750917106 3,721 3,567 2,316.23 118 2,260.00 0.0000
2022-02-14 2021-12-31 13F RAMBUS INC DEL COM 750917106 154 0 0.00 5 66.67 0.0000
2022-02-14 2021-09-30 13F/A-1 RAMBUS INC DEL COM 750917106 154 74 92.50 3 50.00 0.0000
2021-11-15 2021-09-30 13F RAMBUS INC DEL COM 750917106 154 74 3 0.0000
2021-08-13 2021-06-30 13F RAMBUS INC DEL COM 750917106 80 -67 -45.58 2 -33.33 0.0000
2021-05-14 2021-03-31 13F RAMBUS INC DEL COM 750917106 147 147 3 0.0000
2020-11-13 2020-09-30 13F RAMBUS INC DEL COM 750917106 0 -3 -100.00 0 0.0000
2020-08-24 2020-06-30 13F/A-1 RAMBUS INC DEL COM 750917106 3 3 0 0.0000
2020-08-13 2020-06-30 13F RAMBUS INC DEL COM 750917106 3 3 0 0.0000
2020-05-14 2020-03-31 13F RAMBUS INC DEL COM 750917106 0 -50 -100.00 0 -100.00
2020-02-07 2019-12-31 13F RAMBUS INC DEL COM 750917106 50 -36 -41.86 1 0.00 0.0000
2019-11-13 2019-09-30 13F RAMBUS INC DEL COM 750917106 86 59 218.52 1 0.0000
2019-08-13 2019-06-30 13F RAMBUS INC DEL COM 750917106 27 27 0 0.0000
2019-02-13 2018-12-31 13F RAMBUS INC DEL COM 750917106 0 -241 -100.00 0 -100.00
2018-11-09 2018-09-30 13F RAMBUS INC DEL COM 750917106 241 -1,788,259 -99.99 3 -99.99 0.0000
2017-05-11 2017-03-31 13F RAMBUS INC DEL COM 750917106 1,788,500 -2,485,300 -58.15 23,501 -60.07 0.0030
2017-02-10 2016-12-31 13F RAMBUS INC DEL COM 750917106 4,273,800 -1,541,096 -26.50 58,850 -19.04 0.0079
2016-11-14 2016-09-30 13F RAMBUS INC DEL COM 750917106 5,814,896 -1,472,004 -20.20 72,686 -17.43 0.0097
2016-08-11 2016-06-30 13F RAMBUS INC DEL COM 750917106 7,286,900 -616,200 -7.80 88,026 -19.00 0.0120
2016-05-16 2016-03-31 13F RAMBUS INC DEL COM 750917106 7,903,100 0 0.00 108,668 18.64 0.0150
2016-02-12 2015-12-31 13F RAMBUS INC DEL COM 750917106 7,903,100 -1,507,400 -16.02 91,597 -17.51 0.0123
2015-11-10 2015-09-30 13F RAMBUS INC DEL COM 750917106 9,410,500 -1,299,400 -12.13 111,044 -28.44 0.0158
2015-08-25 2015-06-30 13F/A-1 RAMBUS INC DEL COM 750917106 10,709,900 -28,800 -0.27 155,186 14.92 0.0199
2015-08-13 2015-06-30 13F RAMBUS INC DEL COM 750917106 10,709,900 155,186
2015-05-14 2015-03-31 13F RAMBUS INC DEL COM 750917106 10,738,700 -68,200 -0.63 135,039 12.67 0.0172
2015-02-17 2014-12-31 13F RAMBUS INC DEL COM 750917106 10,806,900 -171,300 -1.56 119,849 -12.52 0.0156
2014-11-14 2014-09-30 13F RAMBUS INC DEL COM 750917106 10,978,200 -294,571 -2.61 137,008 -15.01 0.0186
2014-08-14 2014-06-30 13F RAMBUS INC DEL COM 750917106 11,272,771 -829 -0.01 161,201 33.01 0.0216
2014-05-15 2014-03-31 13F RAMBUS INC DEL COM 750917106 11,273,600 -59,200 -0.52 121,191 12.92 0.0168
2014-02-13 2013-12-31 13F RAMBUS INC DEL COM 750917106 11,332,800 -3,353,400 -22.83 107,321 -22.26 0.0152
2013-11-14 2013-09-30 13F RAMBUS INC DEL COM 750917106 14,686,200 1,228,600 9.13 138,051 19.42 0.0212
2013-09-24 2013-06-30 13F/A-1 RAMBUS INC DEL COM 750917106 13,457,600 13,457,600 115,601 0.0189
2013-08-14 2013-06-30 13F RAMBUS INC DEL COM 750917106 13,457,600 115,601 0.0189
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.