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MLM · Martin Marietta Materials Inc

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Market Cap
$31.90B
Shares
60.07M

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Holders: 1,075
Total Value: $34,299,816,778
Total Shares: 59,478,201
Showing 1–100 of 1,089 holdings by value · page 1 of 11

Institutional Ownership Trend

26 quarters

Holder Concentration

Across 1,075 13F filers · Δ vs Mar 31, 2026
Top Holder
7.9%
Sep 2023 → Jun 2026 · range 7.9% – 12.7%
−0.1 pts
Top 5
29.3%
Sep 2023 → Jun 2026 · range 29.3% – 34.6%
−0.2 pts
Top 10
45.3%
Sep 2023 → Jun 2026 · range 45.3% – 51.5%
−1.1 pts
HHI
281
Sep 2023 → Jun 2026 · range 281 – 380
Broadly held−8

Quarterly Activity

vs Mar 31, 2026
New
110
Increased
362
Decreased
396
Sold Out
113
Unchanged
207
Holder count: -3
Institutional value: -0.5%
Shares held: +1.5%

Top Buyers

vs Mar 31, 2026
Institution Added Now Holds Open

Top Sellers

vs Mar 31, 2026
Institution Sold Now Holds Open

Top New Positions

vs Mar 31, 2026
Institution Acquired Value (USD) Open

Top Sold-Out Positions

vs Mar 31, 2026
Institution Previously Held Last Value (USD) Open
Showing 100 of 1,089
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Holder Value (USD) % of 13F Shares Open
Key facts CIK 916076 CUSIP 573284106 13F (30d) 713 filings 684 filers Visit website Investor relations