Martin Marietta Materials, Inc.
MX ˙ BMV ˙ US5732841060
SecurityMX:MLM / Martin Marietta Materials, Inc.
InstitutionGriffin Asset Management, Inc.
Latest Disclosed Ownership3,850 shares
Latest Disclosed Value $ 2,266,418
Griffin Asset Management, Inc. reports 7.23% decrease in ownership of MLM / Martin Marietta Materials, Inc.

On April 30, 2026 - Griffin Asset Management, Inc. filed a 13F-HR form disclosing ownership of 3,850 shares of Martin Marietta Materials, Inc. (MX:MLM) valued at $2,266,418 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 4,150 shares of Martin Marietta Materials, Inc.. This represents a change in shares of -7.23% 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)
2026-04-30 2026-03-31 13F MARTIN MARIETTA MATLS COM 573284106 3,850 -300 -7.23 2,266 -12.31 0.2556
2026-02-06 2025-12-31 13F MARTIN MARIETTA MATLS COM 573284106 4,150 2,000 93.02 2,584 90.70 0.2796
2025-10-16 2025-09-30 13F MARTIN MARIETTA MATLS COM 573284106 2,150 -46 -2.09 1,355 12.45 0.1523
2025-07-25 2025-06-30 13F MARTIN MARIETTA MATLS COM 573284106 2,196 -20 -0.90 1,206 13.79 0.1424
2025-04-16 2025-03-31 13F MARTIN MARIETTA MATLS COM 573284106 2,216 55 2.55 1,060 -5.11 0.1297
2025-01-22 2024-12-31 13F MARTIN MARIETTA MATLS COM 573284106 2,161 -311 -12.58 1,116 -16.09 0.1311
2024-10-15 2024-09-30 13F MARTIN MARIETTA MATLS COM 573284106 2,472 0 0.00 1,331 -0.67 0.1488
2024-07-23 2024-06-30 13F MARTIN MARIETTA MATLS COM 573284106 2,472 -654 -20.92 1,339 -30.22 0.1551
2024-04-17 2024-03-31 13F MARTIN MARIETTA MATLS COM 573284106 3,126 -221 -6.60 1,919 14.98 0.2289
2024-01-19 2023-12-31 13F MARTIN MARIETTA MATLS COM 573284106 3,347 -65 -1.91 1,670 19.21 0.2117
2023-10-19 2023-09-30 13F MARTIN MARIETTA MATLS COM 573284106 3,412 -985 -22.40 1,401 -31.03 0.1991
2023-08-01 2023-06-30 13F MARTIN MARIETTA MATLS COM 573284106 4,397 -725 -14.15 2,030 11.66 0.2748
2023-05-09 2023-03-31 13F MARTIN MARIETTA MATLS COM 573284106 5,122 -15 -0.29 1,819 4.72 0.2541
2023-01-20 2022-12-31 13F MARTIN MARIETTA MATLS COM 573284106 5,137 -35 -0.68 1,736 4.20 0.2618
2022-10-19 2022-09-30 13F MARTIN MARIETTA MATLS COM 573284106 5,172 -65 -1.24 1,666 6.32 0.2768
2022-07-19 2022-06-30 13F MARTIN MARIETTA MATLS COM 573284106 5,237 -7 -0.13 1,567 -22.35 0.2500
2022-04-12 2022-03-31 13F MARTIN MARIETTA MATLS COM 573284106 5,244 -275 -4.98 2,018 -16.99 0.2615
2022-01-28 2021-12-31 13F MARTIN MARIETTA MATLS COM 573284106 5,519 -35 -0.63 2,431 28.08 0.3019
2021-11-05 2021-09-30 13F MARTIN MARIETTA MATLS COM 573284106 5,554 0 0.00 1,898 -2.87 0.2428
2021-07-28 2021-06-30 13F Martin Marietta Matls COM 573284106 5,554 -6 -0.11 1,954 4.66 0.2356
2021-05-04 2021-03-31 13F Martin Marietta Matls COM 573284106 5,560 0 0.00 1,867 18.24 0.2387
2021-01-27 2020-12-31 13F Martin Marietta Matls COM 573284106 5,560 0 0.00 1,579 20.63 0.2094
2020-11-12 2020-09-30 13F Martin Marietta Matls COM 573284106 5,560 -606 -9.83 1,309 2.75 0.2013
2020-08-18 2020-06-30 13F Martin Marietta Matls COM 573284106 6,166 2,283 58.79 1,274 73.33 0.2038
2020-05-18 2020-03-31 13F Martin Marietta Matls COM 573284106 3,883 2,659 217.24 735 114.91 0.1392
2020-02-11 2019-12-31 13F Martin Marietta Matls COM 573284106 1,224 2 0.16 342 2.09 0.0479
2019-11-05 2019-09-30 13F Martin Marietta Matls COM 573284106 1,222 -672 -35.48 335 -23.17 0.0520
2019-08-19 2019-06-30 13F Martin Marietta Matls COM 573284106 1,894 2 0.11 436 14.44 0.0555
2019-05-08 2019-03-31 13F Martin Marietta Matls COM 573284106 1,892 678 55.85 381 82.30 0.0539
2019-03-01 2018-12-31 13F Martin Marietta Matls COM 573284106 1,214 4 0.33 209 -5.00 0.0353
2018-11-19 2018-09-30 13F Martin Marietta Matls COM 573284106 1,210 3 0.25 220 -18.52 0.0324
2018-08-15 2018-06-30 13F Martin Marietta Matls COM 573284106 1,207 2 0.17 270 8.00 0.0490
2018-05-16 2018-03-31 13F Martin Marietta Matls COM 573284106 1,205 3 0.25 250 -6.02 0.0455
2018-02-20 2017-12-31 13F Martin Marietta Matls COM 573284106 1,202 2 0.17 266 7.69 0.0473
2017-11-15 2017-09-30 13F Martin Marietta Matls COM 573284106 1,200 0 0.00 247 -7.49 0.0446
2017-08-29 2017-06-30 13F Martin Marietta Matls COM 573284106 1,200 1,200 267 0.0714
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.