American Tower Corp /MA/ SEC filings AMT
American Tower Corp /MA/ has 1,001 filings in SEC EDGAR's recent list, going back to May 22, 2017. Its latest annual report, Form ARS, was filed on Apr 8, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Oct 27, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Oct 27, 2026 (results of operations). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| 4 | Insider transaction | Nov 3, 2026 | Oct 30, 2026 |
| 4 | Insider transaction | Oct 30, 2026 | Oct 28, 2026 |
| 144 | Notice of proposed sale | Oct 30, 2026 | — |
| 144 | Notice of proposed sale | Oct 28, 2026 | — |
| 4 | Insider transaction | Oct 22, 2026 | Apr 28, 2023 |
| 4 | Insider transaction | Oct 5, 2026 | Oct 1, 2026 |
| 3 | Initial insider ownership | Sep 23, 2026 | Sep 17, 2026 |
| 4 | Insider transaction | Aug 25, 2026 | Aug 21, 2026 |
| 4 | Insider transaction | Jul 31, 2026 | Jul 29, 2026 |
| 4 | Insider transaction | Jul 30, 2026 | Jul 28, 2026 |
| 144 | Notice of proposed sale | Jul 29, 2026 | — |
| 144 | Notice of proposed sale | Jul 28, 2026 | — |
| 4 | Insider transaction | Jun 3, 2026 | Jun 1, 2026 |
| 4 | Insider transaction | Jun 1, 2026 | May 28, 2026 |
| 4 | Insider transaction | May 20, 2026 | May 20, 2026 |
| 4 | Insider transaction | Apr 30, 2026 | Apr 28, 2026 |
| 3 | Initial insider ownership | Apr 30, 2026 | Apr 27, 2026 |
| SCHEDULE 13G | Ownership over 5% (passive) | Apr 29, 2026 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Apr 28, 2026 | — |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Mar 26, 2026 | — |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 12, 2026 | Mar 10, 2026 |
| 4 | Insider transaction | Mar 6, 2026 | Mar 4, 2026 |
| 4 | Insider transaction | Mar 6, 2026 | Mar 4, 2026 |
| 4 | Insider transaction | Mar 4, 2026 | Mar 2, 2026 |
| 144 | Notice of proposed sale | Mar 4, 2026 | — |
| 4 | Insider transaction | Mar 3, 2026 | Feb 27, 2026 |
| 4 | Insider transaction | Mar 3, 2026 | Feb 27, 2026 |
| 144 | Notice of proposed sale | Mar 2, 2026 | — |
| 144 | Notice of proposed sale | Feb 27, 2026 | — |
| 144 | Notice of proposed sale | Feb 27, 2026 | — |
| 4 | Insider transaction | Feb 27, 2026 | Feb 25, 2026 |
| 4 | Insider transaction | Feb 27, 2026 | Feb 25, 2026 |
| 4 | Insider transaction | Feb 27, 2026 | Feb 25, 2026 |
| 144 | Notice of proposed sale | Feb 25, 2026 | — |
| 4 | Insider transaction | Feb 19, 2026 | Feb 17, 2026 |
| 144 | Notice of proposed sale | Feb 17, 2026 | — |
| 4 | Insider transaction | Jan 6, 2026 | Jan 3, 2026 |
| 4 | Insider transaction | Jan 6, 2026 | Jan 2, 2026 |
| 4 | Insider transaction | Dec 11, 2025 | Dec 9, 2025 |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Dec 11, 2025 | — |
| 144 | Notice of proposed sale | Dec 9, 2025 | — |
| 4 | Insider transaction | Nov 4, 2025 | Oct 31, 2025 |
| 4 | Insider transaction | Oct 3, 2025 | Oct 1, 2025 |
| 4 | Insider transaction | Sep 23, 2025 | Sep 19, 2025 |
| 3 | Initial insider ownership | Aug 29, 2025 | Aug 22, 2025 |
| 4 | Insider transaction | Aug 1, 2025 | Jul 31, 2025 |
| 144 | Notice of proposed sale | Jul 31, 2025 | — |
| 4 | Insider transaction | Jun 3, 2025 | Jun 1, 2025 |
| 4 | Insider transaction | May 16, 2025 | May 14, 2025 |
| 4 | Insider transaction | Apr 2, 2025 | Mar 31, 2025 |
| 4 | Insider transaction | Mar 19, 2025 | Mar 17, 2025 |
| 144 | Notice of proposed sale | Mar 17, 2025 | — |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 12, 2025 | Mar 10, 2025 |
| 4 | Insider transaction | Mar 3, 2025 | Feb 27, 2025 |
| 4 | Insider transaction | Mar 3, 2025 | Feb 27, 2025 |
| 4 | Insider transaction | Mar 3, 2025 | Feb 27, 2025 |
| 4 | Insider transaction | Mar 3, 2025 | Feb 27, 2025 |
| 4 | Insider transaction | Feb 28, 2025 | Feb 26, 2025 |
| 4 | Insider transaction | Feb 28, 2025 | Feb 26, 2025 |
| 144 | Notice of proposed sale | Feb 27, 2025 | — |
| 144 | Notice of proposed sale | Feb 26, 2025 | — |
| 144 | Notice of proposed sale | Feb 26, 2025 | — |
| 4 | Insider transaction | Feb 18, 2025 | Feb 13, 2025 |
| 144 | Notice of proposed sale | Feb 13, 2025 | — |
| 3/A | Form 3/a | Feb 7, 2025 | Feb 5, 2025 |
| 3 | Initial insider ownership | Feb 6, 2025 | Feb 5, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Feb 5, 2025 | — |
| 3 | Initial insider ownership | Jan 24, 2025 | Jan 13, 2025 |
| 4 | Insider transaction | Jan 17, 2025 | Jan 16, 2025 |
| 144 | Notice of proposed sale | Jan 16, 2025 | — |
| 4 | Insider transaction | Jan 7, 2025 | Jan 3, 2025 |
| 4 | Insider transaction | Oct 3, 2024 | Oct 1, 2024 |
| 4 | Insider transaction | Sep 17, 2024 | Sep 13, 2024 |
| 144 | Notice of proposed sale | Sep 13, 2024 | — |
| 4 | Insider transaction | Sep 12, 2024 | Sep 10, 2024 |
| 144 | Notice of proposed sale | Sep 10, 2024 | — |
| 4 | Insider transaction | Sep 5, 2024 | Sep 3, 2024 |
| 144 | Notice of proposed sale | Sep 3, 2024 | — |
| 4 | Insider transaction | Aug 28, 2024 | Aug 26, 2024 |
| 144 | Notice of proposed sale | Aug 26, 2024 | — |
| 4 | Insider transaction | Aug 6, 2024 | Aug 2, 2024 |
| 4 | Insider transaction | Aug 6, 2024 | Aug 2, 2024 |
| 4 | Insider transaction | Aug 6, 2024 | Aug 2, 2024 |
| 4 | Insider transaction | Aug 6, 2024 | Aug 2, 2024 |
| 144 | Notice of proposed sale | Aug 2, 2024 | — |
| 144 | Notice of proposed sale | Aug 2, 2024 | — |
| 144 | Notice of proposed sale | Aug 2, 2024 | — |
| 144 | Notice of proposed sale | Aug 2, 2024 | — |
| 4 | Insider transaction | Jun 6, 2024 | Jun 4, 2024 |
| 144 | Notice of proposed sale | Jun 4, 2024 | — |
| 4 | Insider transaction | Jun 4, 2024 | Jun 1, 2024 |
| 4 | Insider transaction | May 22, 2024 | May 22, 2024 |
| 4 | Insider transaction | May 22, 2024 | May 22, 2024 |
| 4 | Insider transaction | May 7, 2024 | May 3, 2024 |
| 4 | Insider transaction | May 3, 2024 | May 1, 2024 |
| 4 | Insider transaction | May 3, 2024 | May 1, 2024 |
| 144 | Notice of proposed sale | May 3, 2024 | — |
| 4 | Insider transaction | Mar 19, 2024 | Mar 15, 2024 |
| 3 | Initial insider ownership | Mar 19, 2024 | Mar 14, 2024 |
| 3 | Initial insider ownership | Mar 19, 2024 | Mar 14, 2024 |
| 144 | Notice of proposed sale | Mar 15, 2024 | — |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 10, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 10, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 10, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 10, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 10, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 10, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Oct 1, 2023 |
| 4 | Insider transaction | Mar 8, 2024 | Mar 6, 2024 |
| 4 | Insider transaction | Mar 6, 2024 | Mar 4, 2024 |
| 144 | Notice of proposed sale | Mar 6, 2024 | — |
| 4 | Insider transaction | Mar 5, 2024 | Mar 1, 2024 |
| 4 | Insider transaction | Mar 5, 2024 | Mar 1, 2024 |
| 144 | Notice of proposed sale | Mar 4, 2024 | — |
| 4 | Insider transaction | Mar 1, 2024 | Feb 28, 2024 |
| 4 | Insider transaction | Mar 1, 2024 | Feb 28, 2024 |
| 4 | Insider transaction | Mar 1, 2024 | Feb 28, 2024 |
| 4 | Insider transaction | Mar 1, 2024 | Feb 28, 2024 |
| 4 | Insider transaction | Mar 1, 2024 | Feb 28, 2024 |
| 4 | Insider transaction | Mar 1, 2024 | Feb 28, 2024 |
| 144 | Notice of proposed sale | Mar 1, 2024 | — |
| 144 | Notice of proposed sale | Mar 1, 2024 | — |
| 144 | Notice of proposed sale | Feb 28, 2024 | — |
| 4 | Insider transaction | Feb 28, 2024 | Feb 26, 2024 |
| 144 | Notice of proposed sale | Feb 26, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 13, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Jan 26, 2024 | — |
| 4 | Insider transaction | Nov 13, 2023 | Nov 9, 2023 |
| 144 | Notice of proposed sale | Nov 9, 2023 | — |
| 3 | Initial insider ownership | Nov 8, 2023 | Nov 1, 2023 |
| 4 | Insider transaction | Oct 18, 2023 | Oct 16, 2023 |
| 144 | Notice of proposed sale | Oct 16, 2023 | — |
| 4 | Insider transaction | Oct 4, 2023 | Oct 2, 2023 |
| 144 | Notice of proposed sale | Oct 2, 2023 | — |
| 4 | Insider transaction | Aug 21, 2023 | Aug 17, 2023 |
| 4 | Insider transaction | Aug 17, 2023 | Aug 15, 2023 |
| 144 | Notice of proposed sale | Aug 17, 2023 | — |
| 4 | Insider transaction | Aug 14, 2023 | Aug 10, 2023 |
| 144 | Notice of proposed sale | Aug 10, 2023 | — |
| 4 | Insider transaction | Aug 7, 2023 | Aug 3, 2023 |
| 144 | Notice of proposed sale | Aug 3, 2023 | — |
| 4 | Insider transaction | Aug 3, 2023 | Aug 1, 2023 |
| 4 | Insider transaction | Jul 3, 2023 | Jul 1, 2023 |
| 4 | Insider transaction | Jun 5, 2023 | Jun 1, 2023 |
| 4 | Insider transaction | May 24, 2023 | May 24, 2023 |
| 4 | Insider transaction | May 3, 2023 | May 1, 2023 |
| 4 | Insider transaction | May 3, 2023 | May 1, 2023 |
| 4 | Insider transaction | Mar 14, 2023 | Mar 10, 2023 |
| 4 | Insider transaction | Mar 14, 2023 | Mar 10, 2023 |
| 4 | Insider transaction | Mar 14, 2023 | Mar 10, 2023 |
| 4 | Insider transaction | Mar 14, 2023 | Mar 10, 2023 |
| 4 | Insider transaction | Mar 14, 2023 | Mar 10, 2023 |
| 4 | Insider transaction | Mar 14, 2023 | Mar 10, 2023 |
Showing 200 filings, the most recent 200. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
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Company profile
- Industry
- Real Estate Investment Trusts (SIC 6798)
- Listed as
- AMT (NYSE)
- Fiscal year ends
- December 31
- Incorporated in
- DE
- Headquarters
- Boston, MA
- SEC filer status
- Large accelerated filer
- SEC CIK
- 1053507
- Former names
- AMERICAN TOWER SYSTEMS CORP (until May 8, 1998)
Other Real Estate Investment Trusts companies
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- Prologis, Inc. PLD
- Equinix Inc EQIX
- Simon Property Group Inc. SPG
- Digital Realty Trust, Inc. DLR
- Public Storage PSA
- Realty Income Corp O
- Vivmark Residential VMRK
Source: SEC EDGAR filings. This is company-reported data, not investment advice.