MLM (Martin Marietta Materials)

Insider Trading Activity

Every open-market purchase and sale reported by MLM officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.

Form 4 Filings
50
most recent
Open-Market Buys
0
code P
Sales
1
code S
Reporting Insiders
25
current holders
MLM — Recent Form 4 Transactions (latest 2026-08-25)
FiledInsiderRole TypeSharesValue
2026-08-25 Philipp Niemann Director A
2026-08-04 Michael J Petro SVP and CFO F
2026-06-02 MARTIN J LYONS Director A
2026-06-02 Thomas Pike Director A
2026-06-02 DAVID C WAJSGRAS Director A
2026-05-18 Dorothy M Ables Director A
2026-05-18 GAYLA J DELLY Director A
2026-05-18 Anthony R Foxx Director A
2026-05-18 MARTIN J LYONS Director A
2026-05-18 Mary T Mack Director A
2026-05-18 LAREE E PEREZ Director A
2026-05-18 Thomas Pike Director A
2026-05-18 DONALD W SLAGER Director A
2026-05-18 DAVID C WAJSGRAS Director A
2026-05-05 Christopher William Samborski EVP, COO A
2026-03-03 Donald A. McCunniff EVP and CHRO A
2026-03-03 C Howard Nye Chairman, Pres & CEO A
2026-03-03 Michael J Petro SVP and CFO A
2026-03-03 George Frederick Schoen EVP, GC and Corp. Secretary A
2026-03-02 JOHN J KORALESKI Director A
2026-03-02 Thomas Pike Director A
2026-03-02 DAVID C WAJSGRAS Director A
2026-02-25 Robert J Cardin SVP, Controller & CAO F
2026-02-25 Jason Paul Flynn SVP and CIO F
2026-02-25 Donald A. McCunniff EVP and CHRO F
2026-02-25 C Howard Nye Chairman, Pres & CEO F
2026-02-25 Michael J Petro SVP and CFO F
2026-02-24 Robert J Cardin SVP, Controller & CAO A
2026-02-24 Jason Paul Flynn SVP and CIO A
2026-02-24 Donald A. McCunniff EVP and CHRO A
2026-02-24 C Howard Nye Chairman, Pres & CEO A
2026-02-24 Michael J Petro SVP and CFO A
2026-02-19 Robert J Cardin SVP, Controller & CAO MIXED
2026-02-19 C Howard Nye Chairman, Pres & CEO MIXED
2026-02-19 Jason Paul Flynn SVP and CIO MIXED
2026-02-19 Michael J Petro SVP and CFO MIXED
2025-12-17 ROSELYN R BAR Executive Vice President F
2025-12-17 Robert J Cardin SVP, Controller & CAO F
2025-12-17 Donald A. McCunniff EVP and CHRO F
2025-12-17 C Howard Nye Chairman, Pres & CEO F
2025-12-03 ROSELYN R BAR Executive Vice President MIXED
2025-12-03 Jason Paul Flynn SVP and CIO F
2025-12-01 JOHN J KORALESKI Director A
2025-12-01 Thomas Pike Director A
2025-12-01 DAVID C WAJSGRAS Director A
2025-09-02 JOHN J KORALESKI Director A
2025-09-02 Thomas Pike Director A
2025-09-02 DAVID C WAJSGRAS Director A
2025-08-11 LAREE E PEREZ Director Sell
2025-07-09 Michael J Petro SVP and CFO A
MLM — Current Insider Holders
InsiderRole Shares HeldValue
10%+ Owner 5,381,235
10%+ Owner 5,181,235
10%+ Owner 5,082,564
10%+ Owner 4,709,835
10%+ Owner 3,696,132
Chairman, Pres & CEO 246,438
Executive Vice President 62,594
Exec. VP 60,601
EVP and CFO 59,786
Sr. VP 49,445
Exec VP 47,500
SVP Human Resources 40,073
EVP and CFO 26,643
Director 24,644
EVP, GC and Corp. Secretary 23,673
Director 23,576
Executive VP 22,301
SVP/Controller/CAO 22,027
EVP, COO 21,762
Director 21,306
SVP - Strategy and Development 19,065
Director 17,874
Director 17,869
Director 17,775
Director 17,026
How to read Form 4 activity

Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.

Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.

Full filing history and per-insider positions are on the MLM quote page; the site-wide leaderboard is on the insider transactions hub.