Martin Marietta Materials, Inc.
MX ˙ BMV ˙ US5732841060
SecurityMX:MLM / Martin Marietta Materials, Inc.
InstitutionHartland & Co., LLC
Latest Disclosed Ownership4,318 shares
Latest Disclosed Value $ 2,541,921
Hartland & Co., LLC reports 5.68% increase in ownership of MLM / Martin Marietta Materials, Inc.

On May 6, 2026 - Hartland & Co., LLC filed a 13F-HR form disclosing ownership of 4,318 shares of Martin Marietta Materials, Inc. (MX:MLM) valued at $2,541,921 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 9, 2026 disclosing 4,086 shares of Martin Marietta Materials, Inc.. This represents a change in shares of 5.68% during the quarter.

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)
2026-05-06 2026-03-31 13F MARTIN MARIETTA MATLS COM 573284106 4,318 232 5.68 2,542 -0.12 0.0232
2026-02-09 2025-12-31 13F MARTIN MARIETTA MATLS COM 573284106 4,086 182 4.66 2,544 3.41 0.0321
2025-11-10 2025-09-30 13F MARTIN MARIETTA MATLS COM 573284106 3,904 -3,776 -49.17 2,461 -41.65 0.0323
2025-08-08 2025-06-30 13F MARTIN MARIETTA MATLS COM 573284106 7,680 1,251 19.46 4,216 37.19 0.0592
2025-05-13 2025-03-31 13F MARTIN MARIETTA MATLS COM 573284106 6,429 1,976 44.37 3,074 33.67 0.0477
2025-02-10 2024-12-31 13F MARTIN MARIETTA MATLS COM 573284106 4,453 108 2.49 2,300 -1.67 0.0349
2024-11-13 2024-09-30 13F MARTIN MARIETTA MATLS COM 573284106 4,345 2,493 134.61 2,339 133.10 0.0363
2024-08-12 2024-06-30 13F MARTIN MARIETTA MATLS COM 573284106 1,852 373 25.22 1,003 11.57 0.0171
2024-05-14 2024-03-31 13F MARTIN MARIETTA MATLS COM 573284106 1,479 123 9.07 899 32.99 0.0445
2024-02-12 2023-12-31 13F MARTIN MARIETTA MATLS COM 573284106 1,356 25 1.88 677 23.81 0.0359
2023-11-13 2023-09-30 13F/A-1 MARTIN MARIETTA MATLS COM 573284106 1,331 39 3.02 546 -8.39 0.0336
2023-11-07 2023-09-30 13F MARTIN MARIETTA MATLS COM 573284106 1,331 39 546 0.0300
2023-08-07 2023-06-30 13F MARTIN MARIETTA MATLS COM 573284106 1,292 -3 -0.23 597 29.85 0.0362
2023-05-09 2023-03-31 13F MARTIN MARIETTA MATLS COM 573284106 1,295 -29 -2.19 460 2.68 0.0335
2023-02-14 2022-12-31 13F MARTIN MARIETTA MATLS COM 573284106 1,324 -48 -3.50 447 1.13 0.0350
2022-11-15 2022-09-30 13F MARTIN MARIETTA MATLS COM 573284106 1,372 223 19.41 442 28.49 0.0407
2022-08-12 2022-06-30 13F MARTIN MARIETTA MATLS COM 573284106 1,149 21 1.86 344 -20.74 0.0268
2022-05-04 2022-03-31 13F MARTIN MARIETTA MATLS COM 573284106 1,128 1,096 3,425.00 434 3,000.00 0.0294
2022-02-14 2021-12-31 13F MARTIN MARIETTA MATLS COM 573284106 32 -117 -78.52 14 -72.55 0.0010
2021-11-12 2021-09-30 13F MARTIN MARIETTA MATLS COM 573284106 149 117 365.62 51 363.64 0.0038
2021-08-12 2021-06-30 13F MARTIN MARIETTA MATLS COM 573284106 32 0 0.00 11 0.00 0.0008
2021-05-14 2021-03-31 13F MARTIN MARIETTA MATLS COM 573284106 32 0 0.00 11 22.22 0.0009
2021-02-11 2020-12-31 13F MARTIN MARIETTA MATLS COM 573284106 32 0 0.00 9 12.50 0.0008
2020-11-12 2020-09-30 13F MARTIN MARIETTA MATLS COM 573284106 32 0 0.00 8 14.29 0.0009
2020-08-11 2020-06-30 13F MARTIN MARIETTA MATLS COM 573284106 32 0 0.00 7 16.67 0.0008
2020-05-14 2020-03-31 13F MARTIN MARIETTA MATLS COM 573284106 32 32 6 0.0009
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.