Form 8-K

8-K — Archer Aviation Inc.

Accession: 0001824502-26-000075

Filed: 2026-09-24

Period: 2026-09-18

CIK: 0001824502

SIC: 3721 (AIRCRAFT)

Item: Regulation FD Disclosure

Documents

8-K — achr-20260924.htm (Primary)

EX-99.1 (exhibit_991.htm)

GRAPHIC (exhibit_991001.jpg)

GRAPHIC (exhibit_991002.jpg)

GRAPHIC (exhibit_991003.jpg)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: achr-20260924.htm · Sequence: 1

achr-20260924

0001824502FALSE00018245022026-09-182026-09-180001824502us-gaap:CommonClassAMember2026-09-182026-09-18

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): September 18, 2026

Archer Aviation Inc.

(Exact Name of Registrant as Specified in its Charter)

Delaware 001-39668 85-2730902

(State or other jurisdiction

of incorporation)

(Commission File Number) (IRS Employer Identification No.)

190 West Tasman Drive

San Jose, CA

95134

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: 650-272-3233

N/A

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading

Symbol(s)

Name of each exchange

on which registered

Class A common stock, par value $0.0001 per share ACHR New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 7.01 Regulation FD Disclosure.

On September 24, 2026, Archer Aviation Inc. (the “Company”) issued a press release announcing the expiration of the required waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, with respect to its previously announced transaction with The Boeing Company (“Boeing”) pursuant to which the Company has agreed to acquire all of the equity interests of Wisk Aero LLC, SkyGrid, LLC, and Insitu, Inc., together with certain of their respective related entities (the “Acquisition”). Completion of the Acquisition remains subject to the satisfaction or waiver of certain other closing conditions, including receipt of certain other regulatory approvals, as described more fully in the Form 8-K filed by the Company on August 10, 2026.

A copy of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K.

The information in this Item 7.01 of this Current Report on Form 8-K is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of such section, nor shall it be deemed incorporated by reference in any filing under the Exchange Act or the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

Forward-looking Statements

This Current Report on Form 8-K contains certain statements that are not historical facts but are forward-looking statements for purposes of the safe harbor provisions under the Private Securities Litigation Reform Act of 1995. Forward-looking statements generally are accompanied by words such as “believe,” “may,” “will,” “estimate,” “continue,” “anticipate,” “intend,” “expect,” “should,” “would,” “plan,” “predict,” “potential,” “seem,” “seek,” “future,” “outlook,” and similar expressions that predict or indicate future events or trends or that are not statements of historical matters. These forward-looking statements include, but are not limited to, statements regarding future events, including statements about the expected benefits of the Acquisition, the anticipated timing of the closing of the Acquisition and potential impacts on the Company’s business, and other statements that are not historical facts. These statements are based on the current expectations of the Company’s management and are not predictions of actual performance. These forward-looking statements are provided for illustrative purposes only and are not intended to serve as, and must not be relied on, by any investor as a guarantee, an assurance, a prediction or a definitive statement of fact or probability. Actual events and circumstances are difficult or impossible to predict and will differ from assumptions. Many actual events and circumstances are beyond the control of the Company. These forward-looking statements are only predictions and may differ materially from actual results due to a variety of factors. Factors that might cause or contribute to such differences include, but are not limited to: expected benefits from the Acquisition might not be realized within the expected time frames or at all and costs or difficulties relating to integration matters might be greater than expected; any required regulatory approvals and clearances for the Acquisition may be delayed or may not be obtained (or may result in the imposition of conditions); the other closing conditions may be delayed or may not be obtained, or the equity purchase agreement may be terminated; the Company’s or Boeing’s businesses may experience disruptions due to transaction-related uncertainty or other factors making it more difficult to maintain relationships with employees, customers, other business partners or governmental entities; the possibility that the Acquisition is more expensive to complete than anticipated; diversion of management’s attention from ongoing business operations and opportunities as a result of the Acquisition or otherwise; and those factors detailed in the Company’s filings with the SEC, including the Company’s most recent Annual Report on Form 10-K filed with the SEC. Any forward-looking statements contained herein are based on assumptions that the Company believes to be reasonable as of the date they were made. The Company undertakes no obligation to update these statements as a result of new information or future events.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

Number

Description

99.1

Press Release

104 Cover Page Interactive Data File (formatted in the Inline XBRL and contained in Exhibit 101)

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

ARCHER AVIATION INC.

Date: September 24, 2026 By: /s/ Eric Lentell

Name: Eric Lentell

Title: Chief Strategy Officer

EX-99.1

Filename: exhibit_991.htm · Sequence: 2

exhibit_991

Archer Announces Expiration of Hart-Scott-Rodino Waiting Period for its Acquisition of Boeing’s Wisk Aero, Insitu and SkyGrid Subsidiaries SILICON VALLEY, CA, September 24, 2026 -- Archer Aviation Inc. (NYSE: ACHR) today announced the expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act"), with respect to the previously announced agreements pursuant to which Archer will acquire Boeing’s Wisk Aero, SkyGrid and Insitu subsidiaries. The expiration of the HSR Act waiting period occurred at 11:59 p.m. EDT on September 18, 2026. The expiration of the HSR Act waiting period satisfies a key condition to closing the transaction. Completion of the transaction remains subject to the satisfaction or waiver of other customary closing conditions, including receipt of certain other regulatory approvals, which are underway. The transaction is expected to close by the end of 2026. The transaction is set to create an end-to-end physical AI platform for aerospace and defense, combining Wisk, Insitu and SkyGrid’s pioneering autonomy, electric vertical take off and landing (eVTOL) aircraft, unmanned aircraft systems (UAS) and airspace intelligence technologies with Archer’s product suite and leading purpose-built AI foundation model, ZEE. About Archer

Archer builds the aircraft and core technologies that will define the next era of flight for aerospace and defense. Archer Media Relations Contact: Archer@TheBrandAmp.com Source: Archer Aviation Archer’s Forward-Looking Statements and Disclaimers This press release contains forward-looking statements regarding Archer's future business plans, expectations, and opportunities, including statements regarding the expected timing and structure of the transaction; the ability of the parties to complete the transaction; the expected benefits of the transaction, including future financial and operating results and strategic benefits; and plans, objectives, and anticipated benefits of acquisitions, strategic investments, partnerships, and collaborations with third parties. Forward-looking statements are only predictions and may differ materially from actual results due to a variety of factors. These forward-looking statements are based on Archer's current expectations and are subject to risks and uncertainties, which may cause actual results to differ materially from Archer's current expectations. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those indicated or anticipated by such forward-looking statements. The inclusion of such statements should not be regarded as a representation that such plans, estimates or expectations will be achieved. Important factors that could cause actual results to differ materially from such plans, estimates or expectations include, among others, (i) that one or more closing conditions to the transaction, including certain regulatory approvals, may not be satisfied or waived, on a timely basis or otherwise, including that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction, or may require conditions, limitations or restrictions in connection with such approvals; (ii) the risk that the transaction may not be completed on the terms or in the time frame expected by Archer, or at all; (iii) unexpected costs, charges or expenses resulting from the transaction; (iv) uncertainty of the expected financial performance of Archer following completion of the transaction; (v) failure to realize the anticipated benefits of the transaction, including as a result of delay in completing the transaction or integrating the businesses, on the expected timeframe or at all; (vi) the occurrence of any event that could give rise to termination of the transaction; (vii) the risk that stockholder litigation in connection with the transaction or other litigation, settlements or investigations may affect the timing or occurrence of the transaction or result in significant costs of defense, indemnification and liability; (viii) risks related to the disruption of management time from ongoing business operations due to the pendency of the transaction, or other effects of the pendency of the transaction on the relationship of any of the parties to the transaction with their employees, customers, suppliers or other counterparties; and (ix) other risk factors detailed from time to time in Archer's reports filed with the Securities and Exchange Commission (the "SEC"), including documents that will be filed with the SEC in connection with the transaction. Any forward-looking

statements contained herein are based on assumptions that Archer believes to be reasonable as of the date of this press release. Archer undertakes no obligation to update these statements as a result of new information or future events.

GRAPHIC

Filename: exhibit_991001.jpg · Sequence: 7

Binary file (144847 bytes)

Download exhibit_991001.jpg

GRAPHIC

Filename: exhibit_991002.jpg · Sequence: 8

Binary file (271166 bytes)

Download exhibit_991002.jpg

GRAPHIC

Filename: exhibit_991003.jpg · Sequence: 9

Binary file (40277 bytes)

Download exhibit_991003.jpg

XML — IDEA: XBRL DOCUMENT

XML

Filename: R1.htm · Sequence: 11

v3.26.3

Cover Cover

Sep. 18, 2026

Document Information [Line Items]

Document Type

8-K

Entity Registrant Name

Archer Aviation Inc.

Entity Incorporation, State or Country Code

Entity File Number

001-39668

Entity Tax Identification Number

85-2730902

Entity Address, Address Line One

190 West Tasman Drive

Entity Address, City or Town

San Jose

Entity Address, State or Province

Entity Address, Postal Zip Code

95134

City Area Code

650

Local Phone Number

272-3233

Written Communications

false

Soliciting Material

false

Pre-commencement Tender Offer

false

Pre-commencement Issuer Tender Offer

false

Entity Emerging Growth Company

false

Entity Central Index Key

0001824502

Amendment Flag

false

Common Class A

Document Information [Line Items]

Title of 12(b) Security

Class A common stock, par value $0.0001 per share

Trading Symbol

ACHR

Security Exchange Name

NYSE

- Definition

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

+ References

No definition available.

+ Details

Name:

dei_AmendmentFlag

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Area code of city

+ References

No definition available.

+ Details

Name:

dei_CityAreaCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:

dei_DocumentInformationLineItems

Namespace Prefix:

dei_

Data Type:

xbrli:stringItemType

Balance Type:

Period Type:

duration

- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

+ Details

Name:

dei_DocumentType

Namespace Prefix:

dei_

Data Type:

dei:submissionTypeItemType

Balance Type:

Period Type:

duration

- Definition

Address Line 1 such as Attn, Building Name, Street Name

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine1

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Name of the City or Town

+ References

No definition available.

+ Details

Name:

dei_EntityAddressCityOrTown

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Code for the postal or zip code

+ References

No definition available.

+ Details

Name:

dei_EntityAddressPostalZipCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Name of the state or province.

+ References

No definition available.

+ Details

Name:

dei_EntityAddressStateOrProvince

Namespace Prefix:

dei_

Data Type:

dei:stateOrProvinceItemType

Balance Type:

Period Type:

duration

- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityCentralIndexKey

Namespace Prefix:

dei_

Data Type:

dei:centralIndexKeyItemType

Balance Type:

Period Type:

duration

- Definition

Indicate if registrant meets the emerging growth company criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityEmergingGrowthCompany

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

+ References

No definition available.

+ Details

Name:

dei_EntityFileNumber

Namespace Prefix:

dei_

Data Type:

dei:fileNumberItemType

Balance Type:

Period Type:

duration

- Definition

Two-character EDGAR code representing the state or country of incorporation.

+ References

No definition available.

+ Details

Name:

dei_EntityIncorporationStateCountryCode

Namespace Prefix:

dei_

Data Type:

dei:edgarStateCountryItemType

Balance Type:

Period Type:

duration

- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityRegistrantName

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityTaxIdentificationNumber

Namespace Prefix:

dei_

Data Type:

dei:employerIdItemType

Balance Type:

Period Type:

duration

- Definition

Local phone number for entity.

+ References

No definition available.

+ Details

Name:

dei_LocalPhoneNumber

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 13e

-Subsection 4c

+ Details

Name:

dei_PreCommencementIssuerTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14d

-Subsection 2b

+ Details

Name:

dei_PreCommencementTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Title of a 12(b) registered security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b

+ Details

Name:

dei_Security12bTitle

Namespace Prefix:

dei_

Data Type:

dei:securityTitleItemType

Balance Type:

Period Type:

duration

- Definition

Name of the Exchange on which a security is registered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection d1-1

+ Details

Name:

dei_SecurityExchangeName

Namespace Prefix:

dei_

Data Type:

dei:edgarExchangeCodeItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14a

-Subsection 12

+ Details

Name:

dei_SolicitingMaterial

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Trading symbol of an instrument as listed on an exchange.

+ References

No definition available.

+ Details

Name:

dei_TradingSymbol

Namespace Prefix:

dei_

Data Type:

dei:tradingSymbolItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 230

-Section 425

+ Details

Name:

dei_WrittenCommunications

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Details

Name:

us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember

Namespace Prefix:

Data Type:

Balance Type:

Period Type: