Elena Marquez - 09 Oct 2026 Form 4 Insider Report for Anterix Inc. (ATEX)

Reporting relationship: Chief Financial Officer
Issuer ticker: ATEX
Reported as of: 09 Oct 2026
Net transaction value: -$400,607
SEC form: 4
Accepted by SEC: 13 Oct 2026, 07:57:25 UTC
Prior SEC filing: 06 Oct 2026
Source filing: View source filing
Reporting owner signature: /s/ Gena L. Ashe, Attorney-in-Fact

Filing notes and source

Key filing fact

Elena Marquez filed Form 4 for Anterix Inc. (ATEX) on 13 Oct 2026.

Key facts

This page summarizes Elena Marquez's Form 4 filing for Anterix Inc. (ATEX).
7 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 13 Oct 2026, 07:57.

Change

Previous filing in this sequence was filed on 06 Oct 2026.
Current net transaction value: -$400,607.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0002090789 Primary reporting owner

Marquez Elena

Relationship: Chief Financial Officer
Address: 3 GARRET MOUNTAIN PLAZA, SUITE 401, WOODLAND PARK
Signature: /s/ Gena L. Ashe, Attorney-in-Fact
Signature date: 09 Oct 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

ATEX transaction

Common Stock

Sale

Transaction value: -$260,849
Shares: -3,254
Change %: -20%
Price: $80.16
Shares after: 13,104
Date: 09 Oct 2026
Ownership: Direct
Footnotes: F1, F2

ATEX transaction

Common Stock

Sale

Transaction value: -$32,720
Shares: -400
Change %: -3.1%
Price: $81.80
Shares after: 12,704
Date: 09 Oct 2026
Ownership: Direct
Footnotes: F1, F3

ATEX transaction

Common Stock

Sale

Transaction value: -$8,250
Shares: -100
Change %: -0.79%
Price: $82.50
Shares after: 12,604
Date: 09 Oct 2026
Ownership: Direct
Footnotes: F1

ATEX transaction

Common Stock

Options Exercise

Transaction value
Shares: +1,227
Change %: +9.7%
Price: $40.00^*
Shares after: 13,831
Date: 09 Oct 2026
Ownership: Direct

ATEX transaction

Common Stock

Sale

Transaction value: -$81,589
Shares: -1,017
Change %: -7.4%
Price: $80.22
Shares after: 12,814
Date: 09 Oct 2026
Ownership: Direct
Footnotes: F1, F2

ATEX transaction

Common Stock

Sale

Transaction value: -$17,199
Shares: -210
Change %: -1.6%
Price: $81.90
Shares after: 12,604
Date: 09 Oct 2026
Ownership: Direct
Footnotes: F1, F4

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

ATEX transaction Derivative

Stock Option (Right to Buy)

Options Exercise

Transaction value
Shares: -1,227
Change %: -50%
Price: $0.000000^*
Shares after: 1,227
Date: 09 Oct 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 1,227
Exercise price: $40.00
Footnotes: F5

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 5 footnotes

Footnote F1

The sale of shares was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on June 22, 2026.

Footnote F2

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $80.00 to $80.53, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of securities sold at each separate price within the ranges set forth in this footnote to this Form 4.

Footnote F3

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $81.45 to $82.00, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of securities sold at each separate price within the ranges set forth in this footnote to this Form 4.

Footnote F4

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $81.765 to $82.00, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of securities sold at each separate price within the ranges set forth in this footnote to this Form 4.

Footnote F5

The option shares vest and become exercisable in three equal annual installments beginning on October 4, 2025