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RMBS Institutional Ownership & 13F Holders | SmartMoneyDB

RMBSRAMBUS INC DEL

COM · CUSIP 750917106

Smart Money Ownership

Of the 13 tracked institutions holding RMBS, 7 have a 3-year clone track record — 6 of them beat the S&P. Average holder's clone alpha: +4.6pt. It's a gauge of who owns the name, not just how many.

RMBS (RAMBUS INC DEL) Institutional Ownership Summary

Among the 13 tracked institutional investors we monitor, RMBS (RAMBUS INC DEL) is held with a combined value of $3.75B across 42,743,958 shares. The largest holder is BlackRock, Inc. with a position worth $1.40B (0.02% of their portfolio). MAVERICK CAPITAL LTD opened a new position in the most recent quarter. 5 funds increased their holdings. 7 funds reduced their position.

Total Institutional Value

$3.75B

Total Shares Held

42,743,958

Institutional Holders

% of Shares Outstanding

39.5%

of 108.14M shares · SEC 2026-03-31

Days to Cover

1.6-6.1%

4.58M shares short · FINRA 2026-07-15

Tracked 13F institutions hold 39.5% of RMBS's shares outstanding. This is a floor: 13F filings arrive on a ~45-day lag and we track only a subset of institutional filers, so true institutional ownership is higher. Shares-outstanding is the latest SEC cover-page figure (as of 2026-03-31), not a live float.

This Quarter's Biggest Movers

Ranked by estimated dollars moved (share change × implied price). 13F data lags up to 45 days.

Biggest Buyers

FMR LLC+109% shares~$149.0M AQR CAPITAL MANAGEMENT LLC+76% shares~$44.8M Fisher Asset Management, LLC+43% shares~$19.0M STATE STREET CORP+3% shares~$10.6M BlackRock, Inc.+0% shares~$2.8M

13F Institutional Holders

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PRICE T ROWE ASSOCIATES INC /MD/

AQR CAPITAL MANAGEMENT LLC

0.05% of book+75.8%

$103.96M

WELLINGTON MANAGEMENT GROUP LLP

0.01% of book-8.3%

$73.69M

Fisher Asset Management, LLC

0.02% of book+42.7%

$63.52M

MILLENNIUM MANAGEMENT LLC

0.01% of book-49.6%

$12.59M

Bridgewater Associates, LP

0.02% of book-66.4%

$4.46M

#	Fund	Value↓	Shares	Portfolio %	Change
1	BlackRock, Inc.	$1.40B	16,305,306	0.02%	+0.2%
2	VANGUARD GROUP INC	$1.13B	12,290,929	0.02%	-3.2%
3	STATE STREET CORP	$376.26M	4,373,617	0.01%	+2.9%
4	PRICE T ROWE ASSOCIATES INC /MD/	$290.50M	3,376,689	0.03%	-37.3%
5	FMR LLC	$285.49M	3,318,449	0.02%	+109.1%
6	AQR CAPITAL MANAGEMENT LLC	$103.96M	1,250,456	0.05%	+75.8%
7	WELLINGTON MANAGEMENT GROUP LLP	$73.69M	856,598	0.01%	-8.3%
8	Fisher Asset Management, LLC	$63.52M	738,356	0.02%	+42.7%
9	MILLENNIUM MANAGEMENT LLC	$12.59M	146,314	0.01%	-49.6%
10	Bridgewater Associates, LP	$4.46M	51,854	0.02%	-66.4%

Frequently Asked Questions

Which institutional investors own the most RMBS stock?

As of the latest SEC 13F filings, BlackRock, Inc. is the largest institutional holder of RMBS with a position worth $1.40B, representing 0.02% of their portfolio. In total, 13 institutional investors hold RMBS with a combined value of $3.75B.

Are hedge funds buying or selling RMBS?

In the most recent quarter, 1 fund opened a new position in RMBS. Additionally, 5 increased their holdings and 7 reduced their positions.

What percentage of RMBS is owned by institutional investors?

Institutional investors hold $3.75B worth of RMBS stock across 13 positions. The largest institutional holder is BlackRock, Inc. with $1.40B in holdings.

What is a 13F filing and why does it matter for RMBS?

A 13F filing is a quarterly report required by the SEC from institutional investment managers with over $100 million in assets. It discloses their holdings in U.S. equities. For RMBS, these filings reveal which major funds are accumulating or reducing positions, providing insights into institutional sentiment.

Track RMBS institutional moves

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