🕵️ American Tower Corp /MA/ ($AMT)
SEC insider & ownership activity, last 12 months · CIK 1053507 · every row links its SEC filing
Over the last 12 months insiders sold $23.2M against $2.0M of open-market buying. Eugene Noel sold $7.9M through a 10b5-1 trading plan in 4 lots (Mar). No red-flag 8-Ks in the window.
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Monthly net open-market insider flow, last 12 months (up = net buying)
Insider flow
2 buyers, $2.0M (3 lots) · 5 sellers, $23.2M (19 lots)
| Insider | Buys | Bought | Sells | Sold | Last |
|---|---|---|---|---|---|
| Eugene Noel | 0 | – | 4 | $7.9M | Mar 2, 2026 |
| Rodney Smith | 0 | – | 4 | $6.6M | Feb 17, 2026 |
| Steven O. Vondran | 0 | – | 3 | $6.3M | Mar 4, 2026 |
| Meyer Robert Joseph | 0 | – | 2 | $1.7M | Jul 29, 2026 |
| Kalathur Rajesh | 2 | $996K | 0 | – | Aug 21, 2026 |
| Eugene F. Reilly | 1 | $994K | 0 | – | Oct 31, 2025 |
| Ruth T. Dowling | 0 | – | 6 | $733K | Jul 29, 2026 |
5%+ holders
| Holder | Stake | Class | Schedule | Event | |
|---|---|---|---|---|---|
| BlackRock, Inc. | 9.2% | 13G | Feb 5, 2025 | filing ↗ | |
| Vanguard Capital Management | 7.6% | 13G | Apr 29, 2026 | filing ↗ | |
| Vanguard Portfolio Management | 5.9% | 13G | Apr 28, 2026 | filing ↗ |
Planned insider sales (Form 144)
| Seller | Planned | Approx. sale date | |
|---|---|---|---|
| Robert Meyer | $894K | Jul 29, 2026 | filing ↗ |
| Ruth T. Dowling | $299K | Jul 28, 2026 | filing ↗ |
| Steven O. Vondran | $6.3M | Mar 4, 2026 | filing ↗ |
| Eugene Noel | $7.9M | Mar 2, 2026 | filing ↗ |
| Ruth T. Dowling | $427K | Feb 27, 2026 | filing ↗ |
| Robert Meyer | $832K | Feb 27, 2026 | filing ↗ |
| Olivier Puech Trust | $3.2M | Feb 25, 2026 | filing ↗ |
| Rodney Smith | $6.6M | Feb 17, 2026 | filing ↗ |
Material events (8-K)
| Item | Event date | |
|---|---|---|
| Material agreement (1.01) | Sep 14, 2026 | filing ↗ |
| New financial obligation (2.03) | Sep 14, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Sep 14, 2026 | filing ↗ |
| Other events (8.01) | Sep 9, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Sep 9, 2026 | filing ↗ |
| Earnings (2.02) | Jul 28, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jul 28, 2026 | filing ↗ |
| Other events (8.01) | Jun 2, 2026 | filing ↗ |
| Other events (8.01) | Jun 2, 2026 | filing ↗ |
| Material agreement (1.01) | May 27, 2026 | filing ↗ |
| New financial obligation (2.03) | May 27, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 27, 2026 | filing ↗ |
| Officer/director changes (5.02) | May 20, 2026 | filing ↗ |
| Shareholder vote (5.07) | May 20, 2026 | filing ↗ |
| Other events (8.01) | May 20, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 20, 2026 | filing ↗ |
| Other events (8.01) | May 19, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 19, 2026 | filing ↗ |
| Material agreement (1.01) | May 7, 2026 | filing ↗ |
| New financial obligation (2.03) | May 7, 2026 | filing ↗ |
| Earnings (2.02) | Apr 28, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Apr 28, 2026 | filing ↗ |
| Officer/director changes (5.02) | Mar 6, 2026 | filing ↗ |
| Other events (8.01) | Mar 5, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Mar 5, 2026 | filing ↗ |
| Officer/director changes (5.02) | Feb 25, 2026 | filing ↗ |
| Earnings (2.02) | Feb 24, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Feb 24, 2026 | filing ↗ |
| Other events (8.01) | Jan 28, 2026 | filing ↗ |
| Officer/director changes (5.02) | Jan 26, 2026 | filing ↗ |