Martin Marietta Materials, Inc.
US ˙ NYSE ˙ US5732841060

SecurityMLM / Martin Marietta Materials, Inc.
InstitutionSei Investments Co
Latest Disclosed Ownership151,114 shares
Latest Disclosed Value $ 94,092,550
Sei Investments Co ownership in MLM / Martin Marietta Materials, Inc.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 151,114 shares of Martin Marietta Materials, Inc. (US:MLM) valued at $94,092,643 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 159,925 shares of Martin Marietta Materials, Inc.. This represents a change in shares of -5.51% during the quarter. The current value of the position is $88,122,129 USD.

Sei Investments Co has a history of taking positions in derivatives of the underlying security (MLM) in the form of stock options.

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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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MLM / Martin Marietta Materials, Inc. Historical Put/Call Ratio
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)
2026-02-13 2025-12-31 13F MARTIN MARIETTA MATLS COM 573284106 151,114 -8,811 -5.51 94,093 -6.65 0.0929
2025-11-13 2025-09-30 13F MARTIN MARIETTA MATLS COM 573284106 159,925 -236 -0.15 100,795 14.64 0.1084
2025-08-14 2025-06-30 13F MARTIN MARIETTA MATLS COM 573284106 160,161 -12,016 -6.98 87,925 6.80 0.1019
2025-05-14 2025-03-31 13F/A-1 MARTIN MARIETTA MATLS COM 573284106 172,177 14,673 9.32 82,323 1.19 0.1060
2025-05-13 2025-03-31 13F MARTIN MARIETTA MATLS COM 573284106 156,829 -675 80,945 0.0880
2025-02-11 2024-12-31 13F MARTIN MARIETTA MATLS COM 573284106 157,504 -2,070 -1.30 81,351 -5.29 0.1045
2024-11-12 2024-09-30 13F MARTIN MARIETTA MATLS COM 573284106 159,574 13,124 8.96 85,894 8.26 0.1115
2024-08-13 2024-06-30 13F MARTIN MARIETTA MATLS COM 573284106 146,450 -2,577 -1.73 79,343 -13.28 0.1124
2024-05-07 2024-03-31 13F MARTIN MARIETTA MATLS COM 573284106 149,027 -118 -0.08 91,495 22.96 0.1341
2024-02-14 2023-12-31 13F MARTIN MARIETTA MATLS COM 573284106 149,145 2,564 1.75 74,413 23.68 0.1195
2023-11-14 2023-09-30 13F MARTIN MARIETTA MATLS COM 573284106 146,581 10,875 8.01 60,165 -3.97 0.1081
2023-08-11 2023-06-30 13F MARTIN MARIETTA MATLS COM 573284106 135,706 -2,068 -1.50 62,655 28.08 0.1093
2023-05-12 2023-03-31 13F MARTIN MARIETTA MATLS COM 573284106 137,774 11,156 8.81 48,919 14.32 0.0909
2023-02-10 2022-12-31 13F MARTIN MARIETTA MATLS COM 573284106 126,618 6,208 5.16 42,793 10.34 0.0951
2022-11-14 2022-09-30 13F MARTIN MARIETTA MATLS COM 573284106 120,410 -3,039 -2.46 38,783 4.99 0.0865
2022-08-15 2022-06-30 13F MARTIN MARIETTA MATLS COM 573284106 123,449 3,376 2.81 36,939 -20.07 0.0798
2022-05-13 2022-03-31 13F MARTIN MARIETTA MATLS COM 573284106 120,073 635 0.53 46,214 -12.17 0.0929
2022-02-14 2021-12-31 13F MARTIN MARIETTA MATLS COM 573284106 119,438 16,269 15.77 52,616 49.26 0.0987
2021-11-12 2021-09-30 13F MARTIN MARIETTA MATLS COM 573284106 103,169 6,498 6.72 35,251 3.65 0.0740
2021-08-06 2021-06-30 13F MARTIN MARIETTA MATLS COM 573284106 96,671 399 0.41 34,009 5.19 0.0754
2021-05-12 2021-03-31 13F MARTIN MARIETTA MATLS COM 573284106 96,272 -1,123 -1.15 32,330 16.90 0.0815
2021-02-08 2020-12-31 13F MARTIN MARIETTA MATLS COM 573284106 97,395 -4,130 -4.07 27,657 15.80 0.0715
2020-12-04 2020-09-30 13F/A-1 MARTIN MARIETTA MATLS COM 573284106 101,525 -3,285 -3.13 23,883 10.28 0.0692
2020-11-06 2020-09-30 13F MARTIN MARIETTA MATLS COM 573284106 101,566 -3,244 23,893 57,529.0317
2020-08-17 2020-06-30 13F/A-1 MARTIN MARIETTA MATLS COM 573284106 104,810 10,925 11.64 21,656 21.84 0.0672
2020-08-11 2020-06-30 13F MARTIN MARIETTA MATLS COM 573284106 81,555 -12,330 22,796 61,835.3634
2020-05-14 2020-03-31 13F MARTIN MARIETTA MATLS COM 573284106 93,885 11,032 13.32 17,774 -23.28 0.0653
2020-02-06 2019-12-31 13F MARTIN MARIETTA MATLS COM 573284106 82,853 9,877 13.53 23,166 15.74 0.0691
2019-11-12 2019-09-30 13F MARTIN MARIETTA MATLS COM 573284106 72,976 -9,646 -11.67 20,016 5.28 0.0512
2019-08-14 2019-06-30 13F MARTIN MARIETTA MATLS COM 573284106 82,622 -6,291 -7.08 19,012 6.28 0.0621
2019-05-15 2019-03-31 13F MARTIN MARIETTA MATLS COM 573284106 88,913 -66,918 -42.94 17,888 -36.91 0.0601
2019-02-13 2018-12-31 13F MARTIN MARIETTA MATLS COM 573284106 155,831 0 0.00 28,353 0.00 0.1009
2018-11-08 2018-09-30 13F MARTIN MARIETTA MATLS COM 573284106 155,831 23,009 17.32 28,353 -4.42 0.1028
2018-08-03 2018-06-30 13F MARTIN MARIETTA MATLS COM 573284106 132,822 -919 -0.69 29,663 6.99 0.1008
2018-05-11 2018-03-31 13F MARTIN MARIETTA MATLS COM 573284106 133,741 -4,830 -3.49 27,724 -9.49 0.1063
2018-02-08 2017-12-31 13F MARTIN MARIETTA MATLS COM 573284106 138,571 18,209 15.13 30,630 23.40 0.1064
2017-11-06 2017-09-30 13F MARTIN MARIETTA MATLS COM 573284106 120,362 24,465 25.51 24,822 16.28 0.0882
2017-07-31 2017-06-30 13F MARTIN MARIETTA MATLS COM 573284106 95,897 1,394 1.48 21,346 3.50 0.0851
2017-05-05 2017-03-31 13F MARTIN MARIETTA MATLS COM 573284106 94,503 35,209 59.38 20,625 57.02 0.0904
2017-02-02 2016-12-31 13F MARTIN MARIETTA MATLS COM 573284106 59,294 10,792 22.25 13,135 51.20 0.0636
2016-11-04 2016-09-30 13F MARTIN MARIETTA MATLS COM 573284106 48,502 33,856 231.16 8,687 208.93 0.0441
2016-08-11 2016-06-30 13F MARTIN MARIETTA MATLS COM 573284106 14,646 -9,611 -39.62 2,812 -27.34 0.0169
2016-05-10 2016-03-31 13F/A-1 MARTIN MARIETTA MATLS COM 573284106 24,257 -24,740 -50.49 3,870 -42.16 0.0241
2016-02-03 2015-12-31 13F MARTIN MARIETTA MATLS COM 573284106 48,997 8 0.02 6,691 -10.12 0.0408
2015-11-02 2015-09-30 13F/A-1 MARTIN MARIETTA MATLS COM 573284106 48,989 19,770 67.66 7,444 80.02 0.0683
2015-10-30 2015-09-30 13F MARTIN MARIETTA MATLS COM 573284106 48,989 7,445
2015-08-07 2015-06-30 13F/A-1 MARTIN MARIETTA MATLS COM 573284106 29,219 11,394 63.92 4,135 66.00 0.0374
2015-08-04 2015-06-30 13F MARTIN MARIETTA MATLS COM 573284106 29,219 11,394 4,135 0.0374
2015-05-14 2015-03-31 13F/A-1 MARTIN MARIETTA MATLS COM 573284106 17,825 -8,761 -32.95 2,491 -15.10 0.0216
2015-05-01 2015-03-31 13F MARRONE BIO INNOVATIONS PUT 573284106 17,825 17,825 2,491 0.0216
2015-02-10 2014-12-31 13F MARTIN MARIETTA MATLS COM 573284106 26,586 26,586 2,934 0.0259
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2015-05-01 2015-03-31 13F MARRONE BIO INNOVATIONS PUT 17,825 2,491 n/a n/a n/a
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.