Anterix CMO sells 8,064 shares at $84 avg

Anterix’s chief marketing officer reported tax-related share withholding and an open-market sale totaling 11,529 common shares.

Rhea-AI Filing Summary

Anterix Inc. (ATEX) reported that officer Martin Heather, Chief Marketing Officer and Chief of Staff, disposed of common stock in two transactions. On September 9, 2026, 3,465 shares were withheld to satisfy tax obligations upon partial vesting of restricted stock units. On September 10, 2026, 8,064 shares were sold in an open-market or private transaction at a weighted average price of $84.2011 per share, with individual sale prices ranging from $84.00 to $84.468. No Rule 10b5-1 trading plan is indicated.

Insider Trade Summary

Net Seller: 8,064 shares

Net Sell 2 txns

Insider Martin Heather

Role Chief Marketing Officer

Sold 8,064 shs ($679K)

Type	Security	Shares	Price	Value
Sale	Common Stock F2	8,064	$84.2011	$679K
Tax Withholding	Common Stock F1	3,465	$85.44	$296K

Holdings After Transaction: Common Stock — 26,743 shares (Direct)

Footnotes (2)

1. F1. The shares were withheld by the Issuer to satisfy withholding obligations in connection with the partial vesting and settlement of restricted stock units.
2. F2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $84.468 to $84.00, 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.

Key Figures

Shares sold: 8,064 shares Weighted average sale price: $84.2011 per share Tax-withheld shares: 3,465 shares +2 more

5 metrics

Shares sold 8,064 shares Common stock sale on September 10, 2026

Weighted average sale price $84.2011 per share Common stock sale on September 10, 2026; trades from $84.00 to $84.468

Tax-withheld shares 3,465 shares Shares withheld on September 9, 2026 to satisfy tax obligations on RSU vesting

Tax-withholding reference price $85.44 per share Per-share value used for the 3,465-share withholding on September 9, 2026

Net shares sold (excluding tax withholding) 8,064 shares Net sell direction across reported buy/sell transactions

Key Terms

weighted average price, restricted stock units, withholding obligations, open market or private transaction

4 terms

weighted average price financial

"The price reported in Column 4 is a weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

restricted stock units financial

"partial vesting and settlement of restricted stock units."

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

withholding obligations financial

"shares were withheld by the Issuer to satisfy withholding obligations"

open market or private transaction financial

"Sale in open market or private transaction"

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

What insider transactions did ATEX report for Martin Heather?

Anterix reported that Martin Heather had 3,465 shares of common stock withheld on September 9, 2026 to cover tax obligations from restricted stock unit vesting, and sold 8,064 shares on September 10, 2026 in an open-market or private transaction.

How many Anterix (ATEX) shares did Martin Heather sell and at what price?

On September 10, 2026, Martin Heather sold 8,064 shares of Anterix common stock at a weighted average price of $84.2011 per share, with individual trades executed between $84.00 and $84.468 per share.

What was the 3,465-share transaction reported for ATEX on September 9, 2026?

On September 9, 2026, 3,465 shares of Anterix common stock were withheld by the company to satisfy withholding obligations related to the partial vesting and settlement of restricted stock units held by Martin Heather.

Was Martin Heather’s September 2026 sale of ATEX shares under a Rule 10b5-1 plan?

No. The Form 4 indicates the Rule 10b5-1 checkbox is not marked, and there is no footnote stating that the 8,064-share sale on September 10, 2026 was made pursuant to a Rule 10b5-1 trading plan.

What role does the insider in this ATEX Form 4 hold at Anterix?

The reporting person, Martin Heather, serves as Anterix’s Chief Marketing Officer and is also described as Chief of Staff in the Form 4, making this a transaction by a senior corporate officer.

AI-generated analysis. How Rhea-AI works. Not financial advice.

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Available on EDGAR 09/11/2026 - 04:10 PM Accepted by SEC EDGAR 09/11/2026 - 04:09 PM Learn about SEC filing dates

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Martin Heather

(Last) (First) (Middle)

3 GARRET MOUNTAIN PLAZA, SUITE 401

(Street)

WOODLAND PARK NEW JERSEY 07424

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Anterix Inc. [ ATEX ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)	X	Other (specify below)
	Chief Marketing Officer		Chief of Staff

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
09/09/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	09/09/2026		F		3,465(1)	D	$85.44	34,807	D
Common Stock	09/10/2026		S		8,064	D	$84.2011	26,743(2)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. The shares were withheld by the Issuer to satisfy withholding obligations in connection with the partial vesting and settlement of restricted stock units.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $84.468 to $84.00, 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.

Remarks:

	/s/ Gena L. Ashe, Attorney-in-Fact	09/11/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)