What SEC filings does ADTRAN Holdings, Inc. submit to the SEC?

ADTRAN Holdings, Inc. (ADTN) submits several types of SEC filings including Form 4 (insider transactions), Form 144 (proposed insider sales), 8-K reports (material events such as earnings releases, acquisitions, leadership changes), and periodic reports — the 10-Q (quarterly) and 10-K (annual). All filings are publicly available through SEC EDGAR.

What does a Form 4 filing tell me about ADTN?

A Form 4 for ADTN discloses a transaction by a company insider — typically a director, officer, or 10%+ shareholder. It shows the source-reported date, number of shares, price, and updated ownership. These facts do not establish motive or predict future returns.

How do I interpret an 8-K filing from ADTRAN Holdings, Inc.?

An 8-K signals a material event requiring prompt disclosure. Common triggers include earnings pre-announcements, acquisitions, leadership appointments or departures, credit changes, or regulatory actions. Read the item codes inside the filing to understand exactly what was disclosed before drawing conclusions.

What is the difference between a 10-K and 10-Q for ADTN?

The 10-K is ADTRAN Holdings, Inc.'s annual report with fully audited financial statements, comprehensive MD&A, and complete risk factor disclosures — filed 60–90 days after fiscal year-end. The 10-Q is a lighter quarterly report with unaudited financials filed for the first three quarters. Together they provide a continuous financial picture of the company.

Where can I see all ADTN SEC filings directly on EDGAR?

You can view all historical ADTRAN Holdings, Inc. filings on the SEC EDGAR company page for ADTN. Each filing card on this page links directly to the original SEC document.

How often does ADTRAN Holdings, Inc. file with the SEC?

ADTRAN Holdings, Inc. files one 10-K per year and up to three 10-Qs per year. Form 4 insider transactions must be reported within two business days of each trade, so the frequency depends on how often insiders are buying or selling ADTN shares. 8-K filings occur whenever a material event happens — which can be several times per quarter for an active company.

ADTN SEC Filing News — ADTRAN Holdings, Inc.

Latest SEC filings for ADTRAN Holdings, Inc. (ADTN) explained in plain English. Covers insider buying and selling (Form 4), proposed insider sales (Form 144), material company events (8-K), and quarterly & annual reports (10-Q / 10-K). StrongBuyAnalytics provides navigation and brief excerpts or summaries; original filings remain at the SEC/source links and were authored by their filers, not StrongBuyAnalytics. Filing dates shown are source dates. Coverage and detection can be delayed or incomplete because of SEC availability, amendments, parsing, caching, or outages. Latest source filing date shown: 2026-08-10.

ADTRAN Holdings, Inc. provides networking and communications platforms, software, systems, and services in the United States, Germany, the United Kingdom, and internationally. It operates through two segments, Network Solutions, and Services & Support. It offers residential gateways; ethernet passive optical network ONUs; gigabit passive optical network/XGS-PON ONTs; routers, and switches; edge cloud; carrier ethernet network interface devices; Optical Line Terminals; Packet Aggregation, Copper …

Sector: Technology Industry: Communication Equipment Market Cap: $523.9M

Total Filings

Bullish Classifications

Bearish Classifications

Insider Transactions

Material Events (8-K)

Periodic Reports

Rule-based classifications for ADTN currently lean bearish. Of the 20 filing records displayed, 2 carry bearish classifications (such as insider sales or negative 8-K disclosures) versus 1 bullish. This does not necessarily signal fundamental deterioration — insiders sell for many reasons — but it is worth monitoring alongside the company's core financial metrics.

ADTN Filing Activity Snapshot 2026-04-03 — 2026-08-10

Insider Transactions (Form 4)

1 buy vs 2 sells

Net insider selling in this period — insiders sell for many reasons beyond conviction.

Largest Form 144 Filing

$2.33M

CHRISTOPH GLINGENER · 2026-05-07

148,392 shares · Form 144

Form 144 Notices

Proposed insider sales filed — Form 144 is a notice of intent, not a confirmed transaction. Actual sales are confirmed via Form 4.

Insider Transactions 8 · Forms 3, 4 and 5

A Form 4 is filed within two business days of a company insider — an officer, a director, or a holder of more than ten percent of the stock — changing their position in the shares. All 8 filings in this group are Form 4s for ADTRAN Holdings, Inc.

The difficulty with reading these filings as a group is that a single form type covers transactions that mean entirely different things. An executive spending their own money to buy stock and an executive having shares withheld to pay tax on a vesting grant both appear as a Form 4. Every filing below is therefore tagged with the nature of the underlying transaction, taken from the transaction code reported on the form itself.

Across the 8 insider filings shown, the breakdown is 5 compensation award, 2 open-market sale and 1 open-market purchase. 3 of them involved a discretionary open-market trade; the rest are compensation and administrative mechanics.

What each transaction type means

Compensation award ×5: Shares were granted as compensation rather than purchased. No cash changed hands, so the filing reflects a pay decision by the company, not a judgement about the price.
Open-market sale ×2: The insider sold shares on the open market. Sales may be discretionary or executed automatically under a pre-arranged Rule 10b5-1 trading plan, and a Form 4 does not always make clear which applies.
Open-market purchase ×1: The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.

Form 4 Compensation award Tax / Compensation Filing 2026-08-10

ADTN insider Form 4 filed for equity award, exercise, or tax withholding

Glingener Christoph (Chief Technology Officer) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.

Shares were granted as compensation rather than purchased. No cash changed hands, so the filing reflects a pay decision by the company, not a judgement about the price.

Transactions reported on this filing
Code	Nature	Shares	Price	Value
`A`	Compensation award	27,924	—	—

Filing: Form 4 (Insider Transaction) Insider: Glingener Christoph (Chief Technology Officer) Shares: 27,924

View on SEC EDGAR → Open Filing Document →

Form 4 Open-market purchase Insider Buying 2026-08-07

ADTN insider Santo Timothy P (SVP of Finance; CFO) bought 6,579 shares (~$50.0K)

Santo Timothy P, listed as SVP of Finance; CFO at ADTRAN Holdings, Inc., reported an open-market purchase of 6,579 ADTN shares in a Form 4 filing. Insider buying is often treated as a bullish signal because company insiders are committing their own capital.

The insider bought shares on the open market with their own money. This is the only Form 4 category that requires a discretionary cash outlay at the prevailing price.

Transactions reported on this filing
Code	Nature	Shares	Price	Value
`P`	Open-market purchase	6,579	$7.60	$50.0K

Filing: Form 4 (Insider Transaction) Insider: Santo Timothy P (SVP of Finance; CFO) Shares: 6,579 Est. Value: $50.0K

View on SEC EDGAR → Open Filing Document →

Form 4 Compensation award Tax / Compensation Filing 2026-07-28

ADTN insider Form 4 filed for equity award, exercise, or tax withholding

Shares were granted as compensation rather than purchased. No cash changed hands, so the filing reflects a pay decision by the company, not a judgement about the price.

Transactions reported on this filing
Code	Nature	Shares	Price	Value
`A`	Compensation award	9,384	—	—

Filing: Form 4 (Insider Transaction) Insider: Glingener Christoph (Chief Technology Officer) Shares: 9,384

View on SEC EDGAR → Open Filing Document →

Form 4 Compensation award Tax / Compensation Filing 2026-07-06

ADTN insider Form 4 filed for equity award, exercise, or tax withholding

DelSanto Anne (Director) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.

Shares were granted as compensation rather than purchased. No cash changed hands, so the filing reflects a pay decision by the company, not a judgement about the price.

Transactions reported on this filing
Code	Nature	Shares	Price	Value
`A`	Compensation award	4,399	—	—

Filing: Form 4 (Insider Transaction) Insider: DelSanto Anne (Director) Shares: 4,399

View on SEC EDGAR → Open Filing Document →

Form 4 Open-market sale Insider Selling 2026-05-22

ADTN insider Wilson James Denson Jr (Chief Revenue Officer) sold 9,332 shares (~$137.4K)

Wilson James Denson Jr, listed as Chief Revenue Officer at ADTRAN Holdings, Inc., reported an open-market sale of 9,332 ADTN shares in a Form 4 filing. This is a confirmed insider sale, not just a proposed sale notice.

The insider sold shares on the open market. Sales may be discretionary or executed automatically under a pre-arranged Rule 10b5-1 trading plan, and a Form 4 does not always make clear which applies.

Transactions reported on this filing
Code	Nature	Shares	Price	Value
`S`	Open-market sale	9,332	$14.72	$137.4K
`G`	Gift	10,469	—	—

Filing: Form 4 (Insider Transaction) Insider: Wilson James Denson Jr (Chief Revenue Officer) Shares: 9,332 Est. Value: $137.4K

View on SEC EDGAR → Open Filing Document →

Form 4 Open-market sale Insider Selling 2026-05-11

ADTN insider Glingener Christoph (Chief Technology Officer) sold 148,392 shares (~$2.22M)

Glingener Christoph, listed as Chief Technology Officer at ADTRAN Holdings, Inc., reported an open-market sale of 148,392 ADTN shares in a Form 4 filing. This is a confirmed insider sale, not just a proposed sale notice.

The insider sold shares on the open market. Sales may be discretionary or executed automatically under a pre-arranged Rule 10b5-1 trading plan, and a Form 4 does not always make clear which applies.

Transactions reported on this filing
Code	Nature	Shares	Price	Value
`M`	Option exercise	41,220	$7.01	$289.0K
`S`	Open-market sale	41,220	$14.73	$607.2K
`M`	Option exercise	84,895	$12.17	$1.03M
`S`	Open-market sale	84,895	$15.06	$1.28M
`M`	Option exercise	22,277	$12.17	$271.1K
`S`	Open-market sale	22,277	$15.00	$334.2K
`M`	Option exercise derivative · Stock Option	41,220	—	—
`M`	Option exercise derivative · Stock Options	84,895	—	—
`M`	Option exercise derivative · Stock Option	22,277	—	—

Filing: Form 4 (Insider Transaction) Insider: Glingener Christoph (Chief Technology Officer) Shares: 148,392 Est. Value: $2.22M

View on SEC EDGAR → Open Filing Document →

Form 4 Compensation award Tax / Compensation Filing 2026-04-03

ADTN insider Form 4 filed for equity award, exercise, or tax withholding

Wilson James Denson Jr (Chief Revenue Officer) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.

Shares were granted as compensation rather than purchased. No cash changed hands, so the filing reflects a pay decision by the company, not a judgement about the price.

Transactions reported on this filing
Code	Nature	Shares	Price	Value
`A`	Compensation award	24,908	—	—

Filing: Form 4 (Insider Transaction) Insider: Wilson James Denson Jr (Chief Revenue Officer) Shares: 24,908

View on SEC EDGAR → Open Filing Document →

Form 4 Compensation award Tax / Compensation Filing 2026-04-03

ADTN insider Form 4 filed for equity award, exercise, or tax withholding

Santo Timothy P (SVP of Finance; CFO) filed a Form 4 covering compensation-related activity such as stock awards, option exercises, conversions, or tax withholding. These filings are usually neutral.

Shares were granted as compensation rather than purchased. No cash changed hands, so the filing reflects a pay decision by the company, not a judgement about the price.

Transactions reported on this filing
Code	Nature	Shares	Price	Value
`A`	Compensation award	28,252	—	—

Filing: Form 4 (Insider Transaction) Insider: Santo Timothy P (SVP of Finance; CFO) Shares: 28,252

View on SEC EDGAR → Open Filing Document →

Proposed Insider Sales 2 · Form 144

A Form 144 is a notice of intent to sell restricted or control securities. It is not a record that anything was sold. ADTRAN Holdings, Inc. has 2 such notices in this period.

The distinction matters because a Form 144 is frequently reported as though it were a completed insider sale. The filer may sell all of the shares covered, some of them, or none at all, and there is no obligation to update the notice either way. A sale that is actually executed by an officer or director shows up separately on a Form 4, which is the filing to check before treating a proposed sale as a real one.

Form 144 Proposed Insider Sale 2026-05-20

ADTN Form 144 filed for proposed insider sale by JAMES D WILSON JR (9,332 shares) ~$137.4K

JAMES D WILSON JR filed a Form 144 with the SEC indicating intent to sell ADTN (ADTRAN Holdings, Inc.) shares. Form 144 reflects a proposed sale, not a completed transaction. The actual execution, if any, would typically appear later in a Form 4.

Filing: Form 144 (Proposed Sale Notice) Insider: JAMES D WILSON JR Shares: 9,332 Est. Value: $137.4K

View on SEC EDGAR → Open Filing Document →

Form 144 Proposed Insider Sale 2026-05-07

ADTN Form 144 filed for proposed insider sale by CHRISTOPH GLINGENER (148,392 shares) ~$2.33M

CHRISTOPH GLINGENER filed a Form 144 with the SEC indicating intent to sell ADTN (ADTRAN Holdings, Inc.) shares. Form 144 reflects a proposed sale, not a completed transaction. The actual execution, if any, would typically appear later in a Form 4.

Filing: Form 144 (Proposed Sale Notice) Insider: CHRISTOPH GLINGENER Shares: 148,392 Est. Value: $2.33M

View on SEC EDGAR → Open Filing Document →

Material Events 8 · Form 8-K

An 8-K reports a material event in the window between scheduled reports. There are 8 in this period for ADTRAN Holdings, Inc. Each 8-K names the item number it is filed under, and that number is the fastest way to tell a routine disclosure from a consequential one.

Item 2.02 is an earnings release, Item 5.02 is a change of directors or officers, and Item 1.01 or 2.01 covers a material agreement or a completed acquisition. Item 7.01 and Item 8.01 are the general-purpose disclosure items and carry no fixed meaning on their own.

Form 8-K Material Company Update 2026-08-10