ASP Isotopes affiliate proposes $48K stock sale

J.P. Morgan Securities LLC is listed as broker, and October 16, 2026 is the approximate sale date.

Rhea-AI Filing Summary

ASP Isotopes Inc. is identified as issuer in a Rule 144 notice listing a proposed sale of 21,830 common shares for Heather Kiessling, identified as an affiliate. The shares have an aggregate market value of $47,975.09, with an approximate sale date of October 16, 2026. J.P. Morgan Securities LLC is listed as the broker, and NASDAQ as the exchange.

The notice also lists 400,000 common shares acquired by Kiessling as compensation through a restricted stock award on April 14, 2025. J.P. Morgan Securities LLC, Workplace Solutions, signed as agent and attorney in fact for Kiessling.

Key Figures

Common shares to be sold: 21,830 shares Aggregate market value: $47,975.09 Approximate sale date: October 16, 2026 +2 more

5 metrics

Common shares to be sold 21,830 shares Proposed sale for Heather Kiessling

Aggregate market value $47,975.09 Proposed sale

Approximate sale date October 16, 2026 Proposed sale

Common shares outstanding 153,309,380 shares Issuer information

Common shares acquired 400,000 shares Compensation through a restricted stock award on April 14, 2025

Key Terms

Rule 144, restricted stock award, aggregate market value

3 terms

Rule 144 regulatory

"See the definition of "person" in paragraph (a) of Rule 144"

Rule 144 is a U.S. securities regulation that sets conditions under which restricted or insider-held shares can be legally resold to the public, such as required holding periods, availability of public information, limits on how much can be sold at once, and certain filing requirements. For investors it matters because it determines when previously locked-up shares can enter the market — like a release valve that can increase supply, affect share price, and signal insider intent.

restricted stock award financial

"Acquired as compensation - Restricted Stock Award"

A restricted stock award is company shares given to an employee or executive that cannot be sold or fully owned until certain conditions—like staying with the company for a set time or hitting performance targets—are met. Think of it as a gift that only becomes yours after you fulfill specific obligations; for investors, these awards matter because they can increase the total shares outstanding when they vest, reveal how management is being paid and motivated, and create potential selling pressure when restrictions lift.

aggregate market value financial

"Aggregate market value"

Aggregate market value is the combined price you would pay to buy all outstanding shares of a company or all companies in a group at current market prices — essentially the sum of each stock’s market capitalization. It matters to investors because it shows the overall size and weight of an investment or sector (like the total cost to buy every piece of a puzzle), helps compare scale across companies or markets, and influences index composition and risk exposure.

FAQ

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

How many ASPI shares does Heather Kiessling plan to sell?

The notice lists a proposed sale of 21,830 ASP Isotopes common shares for Heather Kiessling, with an aggregate market value of $47,975.09. J.P. Morgan Securities LLC is listed as the broker, and the approximate sale date is October 16, 2026.

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

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Available on EDGAR 10/16/2026 - 05:23 PM EDT Accepted by SEC EDGAR 10/16/2026 - 05:23 PM EDT Learn about SEC filing dates

Form 144 Filer Information	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 144 NOTICE OF PROPOSED SALE OF SECURITIES PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
FORM 144

144: Filer Information

Filer CIK	0002026548
Filer CCC	XXXXXXXX
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer	ASP Isotopes, Inc.
SEC File Number	001-41555
Address of Issuer	2200 Ross Avenue Suite 4575E Dallas TEXAS 75201
Phone	214-432-8219
Name of Person for Whose Account the Securities are To Be Sold	Heather Kiessling
See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice.
Relationship to Issuer	Affiliate

144: Securities Information

Title of the Class of Securities To Be Sold	Name and Address of the Broker	Number of Shares or Other Units To Be Sold	Aggregate Market Value	Number of Shares or Other Units Outstanding	Approximate Date of Sale	Name the Securities Exchange
Common Stock	J.P. Morgan Securities LLC 270 Park Ave 10th Floor New York NY 10017	21830	47975.09	153309380	10/16/2026	NASDAQ

Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor:

144: Securities To Be Sold

Title of the Class	Date you Acquired	Nature of Acquisition Transaction	Name of Person from Whom Acquired	Is this a Gift?	Date Donor Acquired	Amount of Securities Acquired	Date of Payment	Nature of Payment *
Common Stock	04/14/2025	Acquired as compensation - Restricted Stock Award	ASP Isotopes, Inc. (Issuer)			400000	04/14/2025	N/A

* If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid.

Furnish the following information as to all securities of the issuer sold during the past 3 months by the person for whose account the securities are to be sold.

144: Securities Sold During The Past 3 Months

Nothing to Report

144: Remarks and Signature

Remarks
Date of Notice	10/16/2026
ATTENTION:
The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. If such person has adopted a written trading plan or given trading instructions to satisfy Rule 10b5-1 under the Exchange Act, by signing the form and indicating the date that the plan was adopted or the instruction given, that person makes such representation as of the plan adoption or instruction date.
Signature	J.P. Morgan Securities LLC, Workplace Solutions, as Agent and Attorney in Fact for Heather Kiessling, ASP Isotopes Inc.
ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)