Martin Marietta Materials (MLM) Held by Superinvestors
MARTIN MARIETTA MATERIALS (MLM) is currently held by 5 superinvestors tracked by InsiderSet, with a combined reported market value of approximately $1.20B based on the latest available SEC Form 13F filings for the quarter ended June 30, 2026.
TCI Fund Management is currently the largest disclosed institutional shareholder of MLM tracked by InsiderSet, reporting ownership valued at approximately $758.42M in its June 30, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $629.08M, representing an estimated loss of -17.05% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 100% of the total disclosed MLM value among the investors covered in this analysis. Major shareholders include TCI Fund Management, Gardner Russo & Quinn, Renaissance Technologies LLC, and several other long-term asset managers with concentrated positions in MARTIN MARIETTA MATERIALS (MLM).
This page ranks the largest institutional MLM shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| TCI Fund Management | Chris Hohn | 1.44% | 1,315,109 | $758,423,360 | $629,082,390 | -$129,340,970 | -17.05% |
| Gardner Russo & Quinn | Thomas Russo | 4.56% | 705,367 | $406,784,959 | $337,412,304 | -$69,372,655 | -17.05% |
| Renaissance Technologies LLC | Jim Simons | 0.03% | 31,894 | $18,393,270 | $15,256,495 | -$3,136,775 | -17.05% |
| Sequoia Financial Advisors | 0.04% | 12,292 | $7,088,712 | $5,879,878 | -$1,208,834 | -17.05% | |
| Lountzis Asset Management | Paul Lountzis | 1.49% | 8,179 | $4,716,829 | $3,912,425 | -$804,404 | -17.05% |
Frequently asked questions about MLM
Who are the largest superinvestors holding MLM?
The largest superinvestors holding MLM in the latest SEC Form 13F filings include TCI Fund Management, Gardner Russo & Quinn, Renaissance Technologies LLC, Sequoia Financial Advisors, and Lountzis Asset Management. InsiderSet ranks these superinvestors by their latest reported MLM position.
What does the MLM superinvestors page include?
This page tracks MLM positions reported by a curated group of notable institutional investors and fund managers through SEC Form 13F. MARTIN MARIETTA MATERIALS (MLM) on this page reflects disclosed 13F holdings among those superinvestors, not every institutional shareholder of the stock.
How many superinvestors hold MLM?
InsiderSet currently tracks 5 superinvestors reporting MLM holdings in the latest available 13F data. This is the curated set on this page, not the total number of institutions that own MLM.
How much MLM stock do superinvestors hold?
Superinvestors tracked by InsiderSet disclosed approximately $1.20B in MLM holdings for Q2 2026. This figure is reported 13F value as of the filing period, not necessarily today's market value, and it covers the curated superinvestors on this page rather than every institutional filer.
When were MLM superinvestor holdings last updated?
The latest MLM superinvestor holdings on InsiderSet are based on SEC Form 13F filings for the quarter ended June 30, 2026. Form 13F filings are generally reported after the quarter ends, so the holdings shown represent the latest publicly disclosed positions rather than real-time holdings.
Are superinvestor MLM holdings real-time?
No. Form 13F data is not real-time. It represents positions reported by these superinvestors as of the end of the reporting quarter. A superinvestor may have changed its MLM position after the reporting date.
Are superinvestors buying or selling MLM?
Buying and selling can be analyzed by comparing MLM positions across consecutive 13F reporting periods. InsiderSet's MLM Ownership Changes page shows institutions that increased, reduced, initiated, or exited positions based on reported 13F holdings. View MLM ownership changes.
How have superinvestor MLM holdings changed over time?
InsiderSet tracks MLM holdings among these superinvestors across multiple 13F reporting periods, so holder counts, reported value, and reported shares can be compared over time.