Allerton Jennifer 4

What Happened
Jennifer Allerton, a director of Iron Mountain Inc. (IRM), was granted 1,892 restricted stock units (RSUs) on May 7, 2026 that vested in full on the grant date (transaction code A). To cover income tax withholding on the net settlement, 133 shares were withheld at $126.81 each (transaction code F) for a withholding value of $16,866. Net shares issued to Allerton after withholding: 1,759. The RSUs had no cash exercise price (acquired at $0).

Key Details

• Transaction date: May 7, 2026; Form 4 filed May 11, 2026 (filing date is within the typical two-business-day window).
• Grant: 1,892 RSUs granted and vested (A) at $0 acquisition cost.
• Tax withholding: 133 shares withheld (F) at $126.81/share = $16,866; withholding was done via share surrender (not an open-market sale).
• Net shares delivered to insider: 1,759.
• Shares owned after transaction: not disclosed in the filing.
• Footnotes: F1 — RSUs vest in their entirety on grant date. F2 — Withheld shares satisfy income tax withholding and do not represent a sale.

Context
RSU grants that vest immediately are a form of compensation; the withholding of a portion of shares to satisfy taxes (a net settlement) is routine and should not be read as a market sale. This transaction represents compensation for the director rather than an open-market purchase or strategic sale.