Martin Marietta Materials (MLM) stock: Winston Score and insider trades

Martin Marietta Materials mines and sells crushed stone, sand, and gravel — materials called "aggregates" that are used to build roads, bridges, airports, and buildings. Its main customers are construction companies, government agencies, and contractors across the United States. The company is one of the two largest producers of construction aggregates in the country. Martin Marietta makes money by selling these materials by the ton, and it also has smaller businesses selling cement, concrete, and asphalt. It operates primarily in the United States, with a strong presence in fast-growing states like Texas, Florida, and the Southeast. Its biggest competitive advantage is that aggregates are heavy and expensive to ship, so local quarries face little competition from distant rivals — once you own a quarry near a city, it is very hard for competitors to take that business. The main risk is that demand for aggregates is closely tied to construction spending, which slows sharply during economic downturns or when infrastructure funding is cut.

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