Vanguard Reduces Stake in Martin Marietta Below 5%

Executive Summary

On October 30, 2026, Vanguard Portfolio Management LLC filed Amendment No. 1 to Schedule 13G/A regarding its beneficial ownership of Martin Marietta Materials Inc ($MLM) common stock. The event date triggering the filing was September 30, 2026.

Key Ownership Metrics

• Aggregate Beneficial Ownership: 3,304,239 shares
• Ownership Percentage: 4.65%
• Voting Rights: Sole voting power over 7,194 shares; shared voting power over 0 shares
• Dispositive Rights: Sole dispositive power over 3,304,239 shares; shared dispositive power over 0 shares
• Change in Ownership Status: Item 5 of the filing confirms that as of the reporting date, the reporting person ceased to be the beneficial owner of more than 5 percent of the class of securities.

Filing Context & Significance

This filing is made pursuant to Rule 13d-1(b) as an institutional investment adviser holding securities in the ordinary course of business without activist intent. The drop below the 5% threshold relieves Vanguard of ongoing Schedule 13G filing obligations for this position unless ownership subsequently rises above 5% again. Because this reflects passive institutional portfolio balancing rather than an activist campaign or corporate insider trade, the trading significance is rated as Low.