Martin Marietta Materials insider activity
What the executives and directors of Martin Marietta Materials actually did with their own shares, decoded from their SEC Form 4 filings. Each figure says the stretch of time it covers.
$0
net open-market flow, 12 m
0 open-market buys, 12 m
–
of sale value on 10b5-1 plans, 12 m
566 days since an insider bought, whole record
The tape: three years of insider trades
Open-market buy
Discretionary sale
Planned sale (10b5-1)
Reported-price path
Routine
Every marker sits at the price reported on the Form 4. The line is the monthly median of all prices insiders reported, so the chart needs no market feed; the grey strip is the routine flow (grants, vestings, tax withholding and gifts) that a headline gets wrong by counting it as selling.
The 130 routine events on the chart, as a list
| Date | Insider | Shares |
|---|---|---|
| Sep 1, 2026 | Petro Michael J | 9,331 |
| Aug 31, 2026 | LYONS MARTIN J | 68 |
| Aug 31, 2026 | WAJSGRAS DAVID C | 78 |
| Aug 31, 2026 | Pike Thomas | 66 |
| Aug 3, 2026 | Petro Michael J | 368 |
| May 29, 2026 | LYONS MARTIN J | 61 |
| May 29, 2026 | WAJSGRAS DAVID C | 69 |
| May 29, 2026 | Pike Thomas | 59 |
| May 14, 2026 | LYONS MARTIN J | 313 |
| May 14, 2026 | WAJSGRAS DAVID C | 313 |
| May 14, 2026 | DELLY GAYLA J | 313 |
| May 14, 2026 | PEREZ LAREE E | 313 |
| May 14, 2026 | SLAGER DONALD W | 313 |
| May 14, 2026 | Ables Dorothy M | 313 |
| May 14, 2026 | Pike Thomas | 313 |
| May 14, 2026 | Mack Mary T | 313 |
| May 14, 2026 | Foxx Anthony R | 313 |
| May 1, 2026 | Samborski Christopher William | 8,101 |
| Mar 1, 2026 | McCunniff Donald A. | 3,152 |
| Mar 1, 2026 | Nye C Howard | 8,945 |
| Mar 1, 2026 | Petro Michael J | 3,265 |
| Mar 1, 2026 | Schoen George Frederick | 24K |
| Feb 27, 2026 | WAJSGRAS DAVID C | 56 |
| Feb 27, 2026 | KORALESKI JOHN J | 69 |
| Feb 27, 2026 | Pike Thomas | 47 |
| Feb 24, 2026 | Cardin Robert J | 312 |
| Feb 24, 2026 | Flynn Jason Paul | 207 |
| Feb 20, 2026 | Nye C Howard | 41K |
| Feb 20, 2026 | Cardin Robert J | 3,349 |
| Feb 20, 2026 | Petro Michael J | 3,413 |
| Feb 20, 2026 | Flynn Jason Paul | 1,516 |
| Feb 20, 2026 | McCunniff Donald A. | 1,277 |
| Dec 16, 2025 | BAR ROSELYN R | 66 |
| Dec 16, 2025 | McCunniff Donald A. | 50 |
| Dec 16, 2025 | Nye C Howard | 298 |
| Dec 16, 2025 | Cardin Robert J | 32 |
| Dec 2, 2025 | BAR ROSELYN R | 908 |
| Dec 1, 2025 | Flynn Jason Paul | 123 |
| Nov 28, 2025 | WAJSGRAS DAVID C | 61 |
| Nov 28, 2025 | KORALESKI JOHN J | 75 |
| Nov 28, 2025 | Pike Thomas | 51 |
| Aug 29, 2025 | WAJSGRAS DAVID C | 61 |
| Aug 29, 2025 | KORALESKI JOHN J | 76 |
| Aug 29, 2025 | Pike Thomas | 51 |
| Jul 8, 2025 | Petro Michael J | 1,822 |
| May 30, 2025 | WAJSGRAS DAVID C | 69 |
| May 30, 2025 | KORALESKI JOHN J | 85 |
| May 30, 2025 | Pike Thomas | 58 |
| May 15, 2025 | COLE SUE W | 308 |
| May 15, 2025 | WAJSGRAS DAVID C | 308 |
| May 15, 2025 | KORALESKI JOHN J | 308 |
| May 15, 2025 | PEREZ LAREE E | 308 |
| May 15, 2025 | SLAGER DONALD W | 308 |
| May 15, 2025 | Ables Dorothy M | 308 |
| May 15, 2025 | Pike Thomas | 308 |
| May 15, 2025 | Cardin Robert J | 2,869 |
| May 15, 2025 | Mack Mary T | 308 |
| May 15, 2025 | Foxx Anthony R | 308 |
| Mar 5, 2025 | McCunniff Donald A. | 1,332 |
| Feb 28, 2025 | WAJSGRAS DAVID C | 78 |
Where the shares went, last 12 months
Every Form 4 movement decomposed: what flowed in (grants, vested equity, purchases) and what flowed out (tax withholding, plan sales, discretionary sales, gifts). Counted in shares, because grants carry no price.
The chart, in numbers
| Flow | Shares |
|---|---|
| Granted | 95K |
| Withheld for tax | 17K |
| Gifts | 488 |
| Kept | 78K |
Skin in the game
Directly held shares as reported after each trade, indexed to 100 at the start of the window, up to five years back. Direct holdings only: trust and family-entity positions are per-entity in the filings and do not sum honestly, so this chart refuses to guess. The steps are the trades.
The chart, in numbers
| Insider | Start of the window | Latest reported | Indexed, start = 100 |
|---|---|---|---|
| Nye C Howard | 91K | 176K | 192.8 |
| BAR ROSELYN R | 57K | 63K | 109.3 |
| Nickolas James AJ | 15K | 27K | 176 |
Who holds what
the 14 largest holdings of 26| Insider | Role | Shares held | Buys 12 m | Sales 12 m | 12 m | Last trade |
|---|---|---|---|---|---|---|
| Nye C Howard Chairman, Pres & CEO Last trade Mar 5, 2024 | CEO | 246K | – | – | Mar 5, 2024 | |
| BAR ROSELYN R SVP, General Counsel and Secy Last trade Mar 14, 2024 | Officer | 63K | – | – | Mar 14, 2024 | |
| Nickolas James AJ EVP and CFO | CFO | 27K | – | – | – | |
| Petro Michael J SVP and CFO Last trade Mar 4, 2025 | CFO | 24K | – | – | Mar 4, 2025 | |
| Schoen George Frederick EVP, GC and Corp. Secretary | Officer | 24K | – | – | – | |
| Samborski Christopher William EVP, COO | COO | 22K | – | – | – | |
| Quillen Michael J Last trade May 9, 2018 | Director | 21K | – | – | May 9, 2018 | |
| COLE SUE W Last trade Feb 16, 2024 | Director | 20K | – | – | Feb 16, 2024 | |
| PEREZ LAREE E Last trade Aug 8, 2025 | Director | 16K | – | – | Aug 8, 2025 | |
| Mohr John P SVP - CIO Last trade Jun 10, 2022 | Officer | 15K | – | – | Jun 10, 2022 | |
| Cardin Robert J SVP, Controller & CAO | Officer | 12K | – | – | – | |
| KORALESKI JOHN J Last trade May 13, 2020 | Director | 11K | – | – | May 13, 2020 | |
| LaTorre Craig M Sr. VP, CHRO Last trade Aug 21, 2023 | Officer | 8,634 | – | – | Aug 21, 2023 | |
| McCunniff Donald A. EVP and CHRO Last trade Mar 5, 2025 | Officer | 7,518 | – | – | Mar 5, 2025 |
Open-market trade log
the 60 most recent of 419| Date | Insider | Type | Shares | Price | Value | Since trade | Filed |
|---|---|---|---|---|---|---|---|
| Aug 8, 2025 | PEREZ LAREE E (Director) 1,038 shares $613.32 +0.0% since trade filed Aug 11, 2025 | Discretionary sale | 1,038 | $613.32 | $637K | +0.0% | Aug 11, 2025 |
| Mar 5, 2025 | McCunniff Donald A. (Officer) 1,332 shares $475.00 +29.1% since trade filed Mar 6, 2025 | Discretionary sale | 1,332 | $475.00 | $633K | +29.1% | Mar 6, 2025 |
| Mar 4, 2025 | Petro Michael J (Officer) 550 shares $454.37 +35.0% since trade filed Mar 5, 2025 | Open-market buy | 550 | $454.37 | $250K | +35.0% | Mar 5, 2025 |
| Mar 14, 2024 | BAR ROSELYN R (Officer) 10K shares $603.29 +1.7% since trade filed Mar 15, 2024 | Discretionary sale | 10K | $603.29 | $6.0M | +1.7% | Mar 15, 2024 |
| Mar 5, 2024 | Nye C Howard (CEO) 5,000 shares $604.26 +1.5% since trade filed Mar 6, 2024 | Discretionary sale | 5,000 | $604.26 | $3.0M | +1.5% | Mar 6, 2024 |
| Mar 5, 2024 | Nye C Howard (CEO) 15K shares $604.26 +1.5% since trade filed Mar 6, 2024 | Discretionary sale | 15K | $604.26 | $9.1M | +1.5% | Mar 6, 2024 |
| Feb 16, 2024 | COLE SUE W (Director) 843 shares $541.22 +13.3% since trade filed Feb 20, 2024 | Discretionary sale | 843 | $541.22 | $456K | +13.3% | Feb 20, 2024 |
| Feb 16, 2024 | COLE SUE W (Director) 881 shares $545.64 +12.4% since trade filed Feb 20, 2024 | Discretionary sale | 881 | $545.64 | $481K | +12.4% | Feb 20, 2024 |
| Aug 21, 2023 | LaTorre Craig M (Officer) 1,934 shares $431.68 +42.1% since trade filed Aug 22, 2023 | Discretionary sale | 1,934 | $431.68 | $835K | +42.1% | Aug 22, 2023 |
| Jul 28, 2023 | LaTorre Craig M (Officer) 500 shares $447.09 +37.2% since trade filed Aug 1, 2023 | Discretionary sale | 500 | $447.09 | $224K | +37.2% | Aug 1, 2023 |
| Nov 18, 2022 | COLE SUE W (Director) 1,685 shares $355.61 +72.5% since trade filed Nov 18, 2022 | Discretionary sale | 1,685 | $355.61 | $599K | +72.5% | Nov 18, 2022 |
| Jun 10, 2022 | Mohr John P (Officer) 0 shares $321.75 +90.6% since trade filed Jun 14, 2022 | Discretionary sale | 0 | $321.75 | $145 | +90.6% | Jun 14, 2022 |
| Mar 10, 2021 | Nye C Howard (CEO) 6,948 shares $337.79 filed Mar 11, 2021 | Discretionary sale | 6,948 | $337.79 | $2.3M | – | Mar 11, 2021 |
| Mar 10, 2021 | Nye C Howard (CEO) 10K shares $337.84 filed Mar 11, 2021 | Discretionary sale | 10K | $337.84 | $3.4M | – | Mar 11, 2021 |
| Mar 9, 2021 | Nye C Howard (CEO) 3,052 shares $335.06 filed Mar 11, 2021 | Discretionary sale | 3,052 | $335.06 | $1.0M | – | Mar 11, 2021 |
| Nov 24, 2020 | BAR ROSELYN R (Officer) 10K shares $274.64 filed Nov 24, 2020 | Discretionary sale | 10K | $274.64 | $2.7M | – | Nov 24, 2020 |
| Sep 10, 2020 | COLE SUE W (Director) 468 shares $207.03 filed Sep 10, 2020 | Discretionary sale | 468 | $207.03 | $97K | – | Sep 10, 2020 |
| Sep 8, 2020 | COLE SUE W (Director) 750 shares $209.18 filed Sep 10, 2020 | Discretionary sale | 750 | $209.18 | $157K | – | Sep 10, 2020 |
| Jun 10, 2020 | ZELNAK STEPHEN P JR (Director) 1,350 shares $207.74 filed Jul 10, 2020 late | Discretionary sale | 1,350 | $207.74 | $280K | – | Jul 10, 2020 late |
| Jun 5, 2020 | ZELNAK STEPHEN P JR (Director) 3,500 shares $226.80 filed Jul 10, 2020 late | Discretionary sale | 3,500 | $226.80 | $794K | – | Jul 10, 2020 late |
| Jun 5, 2020 | ZELNAK STEPHEN P JR (Director) 13K shares $225.23 filed Jul 10, 2020 late | Discretionary sale | 13K | $225.23 | $3.0M | – | Jul 10, 2020 late |
| May 21, 2020 | Nye C Howard (CEO) 6,645 shares $177.62 filed May 22, 2020 | Discretionary sale | 6,645 | $177.62 | $1.2M | – | May 22, 2020 |
| May 13, 2020 | KORALESKI JOHN J (Director) 1,000 shares $164.08 filed May 15, 2020 | Open-market buy | 1,000 | $164.08 | $164K | – | May 15, 2020 |
| May 6, 2020 | KORALESKI JOHN J (Director) 1,000 shares $183.54 filed May 6, 2020 | Open-market buy | 1,000 | $183.54 | $184K | – | May 6, 2020 |
| Mar 31, 2020 | ZELNAK STEPHEN P JR (Director) 8 shares $177.24 filed Jul 10, 2020 late | Open-market buy | 8 | $177.24 | $1K | – | Jul 10, 2020 late |
| Dec 31, 2019 | ZELNAK STEPHEN P JR (Director) 5 shares $277.43 filed Jul 10, 2020 late | Open-market buy | 5 | $277.43 | $1K | – | Jul 10, 2020 late |
| Dec 31, 2019 | Grant Daniel L. (Officer) 22 shares $277.35 filed Jul 2, 2020 late | Open-market buy | 22 | $277.35 | $6K | – | Jul 2, 2020 late |
| Dec 13, 2019 | Nye C Howard (CEO) 4,202 shares $276.87 filed Dec 17, 2019 | Discretionary sale | 4,202 | $276.87 | $1.2M | – | Dec 17, 2019 |
| Nov 25, 2019 | KORALESKI JOHN J (Director) 1,000 shares $260.23 filed Nov 25, 2019 | Open-market buy | 1,000 | $260.23 | $260K | – | Nov 25, 2019 |
| Sep 30, 2019 | ZELNAK STEPHEN P JR (Director) 5 shares $271.29 filed Jul 10, 2020 late | Open-market buy | 5 | $271.29 | $1K | – | Jul 10, 2020 late |
| Sep 30, 2019 | Grant Daniel L. (Officer) 14 shares $271.35 filed Jul 2, 2020 late | Open-market buy | 14 | $271.35 | $4K | – | Jul 2, 2020 late |
| Aug 30, 2019 | Nye C Howard (CEO) 7,440 shares $253.52 filed Aug 30, 2019 | Discretionary sale | 7,440 | $253.52 | $1.9M | – | Aug 30, 2019 |
| Aug 1, 2019 | BAR ROSELYN R (Officer) 2,821 shares $246.93 filed Aug 2, 2019 | Discretionary sale | 2,821 | $246.93 | $697K | – | Aug 2, 2019 |
| Aug 1, 2019 | Nye C Howard (CEO) 11K shares $243.66 filed Aug 2, 2019 | Discretionary sale | 11K | $243.66 | $2.7M | – | Aug 2, 2019 |
| Jun 28, 2019 | ZELNAK STEPHEN P JR (Director) 6 shares $226.65 filed Jul 10, 2020 late | Open-market buy | 6 | $226.65 | $1K | – | Jul 10, 2020 late |
| Jun 28, 2019 | Grant Daniel L. (Officer) 10 shares $226.67 filed Jul 2, 2020 late | Open-market buy | 10 | $226.67 | $2K | – | Jul 2, 2020 late |
| Jun 10, 2019 | PEREZ LAREE E (Director) 824 shares $231.80 filed Jun 10, 2019 | Discretionary sale | 824 | $231.80 | $191K | – | Jun 10, 2019 |
| May 6, 2019 | McCunniff Donald A. (Officer) 3,183 shares $220.19 filed May 7, 2019 | Discretionary sale | 3,183 | $220.19 | $701K | – | May 7, 2019 |
| May 6, 2019 | Nye C Howard (CEO) 15K shares $220.48 filed May 7, 2019 | Discretionary sale | 15K | $220.48 | $3.2M | – | May 7, 2019 |
| Mar 29, 2019 | ZELNAK STEPHEN P JR (Director) 6 shares $200.34 filed Jul 10, 2020 late | Open-market buy | 6 | $200.34 | $1K | – | Jul 10, 2020 late |
| Mar 29, 2019 | Grant Daniel L. (Officer) 10 shares $200.33 filed Jul 2, 2020 late | Open-market buy | 10 | $200.33 | $2K | – | Jul 2, 2020 late |
| Mar 5, 2019 | COLE SUE W (Director) 1,500 shares $195.07 filed Mar 6, 2019 | Discretionary sale | 1,500 | $195.07 | $293K | – | Mar 6, 2019 |
| Feb 28, 2019 | McCunniff Donald A. (Officer) 1,563 shares $189.31 filed Feb 28, 2019 | Discretionary sale | 1,563 | $189.31 | $296K | – | Feb 28, 2019 |
| Feb 27, 2019 | McCunniff Donald A. (Officer) 660 shares $190.90 filed Feb 28, 2019 | Discretionary sale | 660 | $190.90 | $126K | – | Feb 28, 2019 |
| Dec 31, 2018 | ZELNAK STEPHEN P JR (Director) 7 shares $168.81 filed Jul 10, 2020 late | Open-market buy | 7 | $168.81 | $1K | – | Jul 10, 2020 late |
| Dec 31, 2018 | Grant Daniel L. (Officer) 12 shares $168.90 filed Jul 2, 2020 late | Open-market buy | 12 | $168.90 | $2K | – | Jul 2, 2020 late |
| Dec 14, 2018 | KORALESKI JOHN J (Director) 1,000 shares $174.07 filed Dec 18, 2018 | Open-market buy | 1,000 | $174.07 | $174K | – | Dec 18, 2018 |
| Nov 9, 2018 | McCunniff Donald A. (Officer) 1,476 shares $185.50 filed Nov 13, 2018 | Discretionary sale | 1,476 | $185.50 | $274K | – | Nov 13, 2018 |
| Oct 1, 2018 | Mohr John P (Officer) 1 shares $185.60 filed Feb 12, 2020 late | Open-market buy | 1 | $185.60 | $232 | – | Feb 12, 2020 late |
| Sep 28, 2018 | ZELNAK STEPHEN P JR (Director) 7 shares $185.91 filed Jul 10, 2020 late | Open-market buy | 7 | $185.91 | $1K | – | Jul 10, 2020 late |
| Sep 28, 2018 | Grant Daniel L. (Officer) 10 shares $185.79 filed Jul 2, 2020 late | Open-market buy | 10 | $185.79 | $2K | – | Jul 2, 2020 late |
| Aug 22, 2018 | McCunniff Donald A. (Officer) 2,250 shares $204.33 filed Aug 24, 2018 | Discretionary sale | 2,250 | $204.33 | $460K | – | Aug 24, 2018 |
| Jul 30, 2018 | ZELNAK STEPHEN P JR (Director) 3,500 shares $202.87 filed Aug 1, 2018 | Open-market buy | 3,500 | $202.87 | $710K | – | Aug 1, 2018 |
| Jul 27, 2018 | KORALESKI JOHN J (Director) 2,400 shares $208.06 filed Jul 30, 2018 | Open-market buy | 2,400 | $208.06 | $499K | – | Jul 30, 2018 |
| Jul 2, 2018 | Mohr John P (Officer) 1 shares $221.16 filed Feb 12, 2020 late | Open-market buy | 1 | $221.16 | $212 | – | Feb 12, 2020 late |
| Jun 29, 2018 | ZELNAK STEPHEN P JR (Director) 5 shares $222.48 filed Jul 10, 2020 late | Open-market buy | 5 | $222.48 | $1K | – | Jul 10, 2020 late |
| Jun 29, 2018 | Grant Daniel L. (Officer) 5 shares $222.50 filed Jul 2, 2020 late | Open-market buy | 5 | $222.50 | $1K | – | Jul 2, 2020 late |
| Jun 13, 2018 | McCunniff Donald A. (Officer) 4,226 shares $230.72 filed Jun 13, 2018 | Discretionary sale | 4,226 | $230.72 | $975K | – | Jun 13, 2018 |
| May 11, 2018 | BAR ROSELYN R (Officer) 727 shares $215.98 filed May 14, 2018 | Discretionary sale | 727 | $215.98 | $157K | – | May 14, 2018 |
| May 11, 2018 | BAR ROSELYN R (Officer) 5,271 shares $213.36 filed May 14, 2018 | Discretionary sale | 5,271 | $213.36 | $1.1M | – | May 14, 2018 |
“Since trade” compares with the latest insider-implied price, not a market quote: these pages are built from filings alone. A role here is the one on that day's Form 4, so somebody promoted since appears under both titles.
Filing hygiene
160 Forms 4, 3 years
0 filed late
7 amendments
1.7 avg. days to file
How to read this
A Form 4 transaction code decides everything. P is an open-market purchase and S an open-market sale; those two are the only codes where an insider chose to trade. A is a grant, M an option exercise or vesting, F shares withheld to cover tax, G a gift. Most “insiders dumped billions” headlines are code F and M mechanics.
Sales flagged 10b5-1 run on a plan the insider adopted in advance; since 2023 every Form 4 carries that flag. Buys have historically predicted returns, sales mostly have not, and this page states filings, not advice.