Iron Mountain Officer Mark Kidd Files Form 144 to Sell 6,000 Shares

Executive Summary

On September 1, 2026, Mark Kidd, an Officer at Iron Mountain Inc ($IRM), filed a Form 144 notice proposing the sale of 6,000 shares of common stock through Fidelity Brokerage Services LLC. The aggregate market value of the proposed transaction is $693,600.00, representing an estimated price of approximately $115.60 per share.

Transaction & Acquisition Details

• Shares to Sell: 6,000 common shares
• Approximate Sale Date: September 1, 2026
• Trading Plan: Executed pursuant to a Rule 10b5-1 trading plan adopted on March 20, 2025.
• Origin of Shares: The shares were acquired through multiple restricted stock vesting events between March 9, 2017, and February 16, 2021, as compensation from the issuer.

Historical Context (Past 3 Months)

Mark Kidd has executed regular monthly sales under the trading plan over the preceding three months:

• June 1, 2026: 6,000 shares for $760,200.00
• July 1, 2026: 6,000 shares for $753,720.00
• August 7, 2026: 6,000 shares for $736,200.00

Market Impact & Significance

With 297,702,812 shares outstanding, this proposed sale represents a negligible portion (<0.01%) of the total float. Because the sale is part of an established Rule 10b5-1 schedule and routine compensation monetization, the trading significance is considered Low.