Form 8-K

8-K — RESEARCH FRONTIERS INC

Accession: 0001493152-26-027517

Filed: 2026-06-05

Period: 2026-06-02

CIK: 0000793524

SIC: 6794 (PATENT OWNERS & LESSORS)

Item: Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing

Item: Financial Statements and Exhibits

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UNITED

STATES

SECURITIES

AND EXCHANGE COMMISSION

WASHINGTON,

D.C. 20549

FORM

8-K

CURRENT

REPORT

PURSUANT

TO SECTION 13 OR 15(d)

THE SECURITIES EXCHANGE ACT OF 1934

DATE

OF REPORT (DATE OF EARLIEST EVENT REPORTED): June 2, 2026

RESEARCH

FRONTIERS INCORPORATED

(EXACT

NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

delaware

000-14893

11-2103466

(STATE

OR OTHER JURISDICTION

(COMMISSION

(IRS

EMPLOYER

INCORPORATION)

FILE

NUMBER)

IDENTIFICATION

NO.)

240

CROSSWAYS PARK DRIVE

WOODBURY,

new york 11797-2033

(ADDRESS

OF PRINCIPAL EXECUTIVE OFFICES AND ZIP CODE)

REGISTRANT’S

TELEPHONE NUMBER, INCLUDING AREA CODE: (516) 364-1902

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 (see General Instruction A.2. below):

☐

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)) [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

Common

Stock, par value $0.0001 per share

REFR

The

NASDAQ Stock Market

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 ☐

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. ☐

Item

3.01. Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing.

June 2, 2026, Research Frontiers Incorporated (the “Company”) received two deficiency notification letters from the Listing

Qualifications Department of The Nasdaq Stock Market LLC (“Nasdaq”).

The

first notification letter advised the Company that, based upon the closing bid price of the Company’s common stock for the 30 consecutive

business days from April 15, 2026 to June 1, 2026, the Company no longer satisfies the $1.00 minimum bid price requirement for continued

listing on The Nasdaq Capital Market, as set forth in Nasdaq Listing Rule 5550(a)(2).

The

second notification letter advised the Company that, based upon Nasdaq’s review of the Company’s Market Value of Listed Securities

(“MVLS”) for the 30 consecutive business days from April 20, 2026 to June 1, 2026, the Company no longer satisfies the $35

million minimum MVLS requirement for continued listing on The Nasdaq Capital Market, as set forth in Nasdaq Listing Rule 5550(b)(2).

The notification letter also noted that the Company does not currently meet the alternative continued listing standards under Nasdaq

Listing Rules 5550(b)(1) and 5550(b)(3), relating to minimum stockholders’ equity and net income from continuing operations, respectively.

The

Nasdaq notifications have no immediate effect on the listing or trading of the Company’s common stock, which will continue to trade

on The Nasdaq Capital Market under the symbol “REFR.”

accordance with Nasdaq Listing Rules 5810(c)(3)(A) and 5810(c)(3)(C), the Company has been provided 180 calendar days, or until November

30, 2026, to regain compliance with the minimum bid price requirement and the MVLS requirement, respectively.

regain compliance with the minimum bid price requirement, the closing bid price of the Company’s common stock must be at least

$1.00 per share for a minimum of ten consecutive business days during the compliance period, unless Nasdaq exercises its discretion to

require a longer period as permitted under its rules.

regain compliance with the MVLS requirement, the Company’s MVLS must close at $35 million or more for a minimum of ten consecutive

business days during the compliance period, unless Nasdaq exercises its discretion to require a longer period as permitted under its

rules.

The

Company intends to monitor the closing bid price of its common stock and its MVLS and will consider available options to regain compliance

with the applicable Nasdaq continued listing requirements. The Company’s objective is to regain compliance through improved market

valuation and bid-price performance, and the Company does not currently intend to effect a reverse stock split for the purpose of regaining

compliance. However, there can be no assurance that the Company will regain compliance with either requirement within the applicable

compliance period, or at all, or that the Company will otherwise remain in compliance with the other Nasdaq continued listing standards.

Item

9.01. Financial Statements and Exhibits.

(c)

Exhibits.

104

Cover Page Interactive Data File (embedded within the Inline

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SIGNATURES

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.

RESEARCH

FRONTIERS INCORPORATED

/s/

Joseph M. Harary

By:

Joseph

M. Harary

Title:

President

and CEO

Dated:

June 5, 2026

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Entity File Number

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Entity Registrant Name

RESEARCH

FRONTIERS INCORPORATED

Entity Central Index Key

0000793524

Entity Tax Identification Number

11-2103466

Entity Incorporation, State or Country Code

Entity Address, Address Line One

240

CROSSWAYS PARK DRIVE

Entity Address, City or Town

WOODBURY

Entity Address, State or Province

Entity Address, Postal Zip Code

11797-2033

City Area Code

(516)

Local Phone Number

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