The cash-and-stock deal would leave Lhoist Group’s Berghmans family with about a 15% stake in Martin Marietta and is expected to close in the second half of 2026.
Martin Marietta Materials said it would merge with limestone supplier Lhoist North America in a cash-and-stock deal worth $13.5 billion, including debt. The company said it would fund the transaction with $7 billion in cash and $6.5 billion in shares, while Lhoist Group’s Berghmans family would own roughly 15% of Martin Marietta when the deal closes. Martin Marietta shares were down about 3% in premarket trading. The transaction is expected to be completed in the second half of 2026, extending Martin Marietta’s reach in construction materials through limestone, a key input for infrastructure and building projects.