KYMR (NASDAQ) affiliate sales reported — Atlas Venture and insiders disclose disposals

Rhea-AI Filing Summary

KYMR (issuer) submitted a Form 144 notice reporting proposed sales of Common Stock by affiliated holders. The filing lists multiple past and proposed dispositions by Atlas Venture funds and individuals, including large block sales on 06/22/2026 and earlier April–June 2026 transactions.

Insights

Securities Compliance Analyst

Form 144 lists proposed and recent insider/resale transactions; no issuer proceeds indicated.

The excerpt shows multiple resale entries by affiliated holders, including Atlas Venture Fund X, L.P. and Atlas Venture Opportunity Fund I, L.P., with specific sale dates and share counts. The filing format signals routine disclosure of proposed sales under Section 144.

Cash‑flow treatment and whether proceeds go to the issuer are not stated in the excerpt; subsequent SEC filings or broker notices will clarify settlement details.

Key Figures

Largest listed sale (example): 243,976 shares Dollar amount (example): $24,182,608.35 Other notable sale: 100,928 shares +3 more

6 metrics

Largest listed sale (example) 243,976 shares sale by Atlas Venture Fund X on 06/22/2026

Dollar amount (example) $24,182,608.35 proceeds shown for 243,976 shares on 06/22/2026

Other notable sale 100,928 shares sale by Atlas Venture Fund X on 06/18/2026

Dollar amount for 06/18/2026 $9,185,730.49 proceeds shown for 100,928 shares on 06/18/2026

Individual sales example 11,741 shares sale by Bruce Booth on 06/17/2026

Aggregate reference number 82,257,588 numeric field appearing near header with date 06/23/2026

Key Terms

Form 144, Private Placement, Issuer, Common Stock

4 terms

Form 144 regulatory

"submitted a Form 144 notice reporting proposed sales"

Form 144 is a document that investors must file with the government when they plan to sell a large number of shares of a company's stock. It helps ensure transparency so everyone knows how many shares are being sold and when, which can impact the stock's price.

Private Placement market

"Common Stock | 03/11/2020 | Private Placement"

A private placement is a way for companies to raise money by selling securities directly to a small group of investors instead of through a public offering. This process is often quicker and less regulated, making it similar to offering a special, exclusive investment opportunity to select individuals or institutions. For investors, it can provide access to unique investment options that are not available on public markets.

Issuer regulatory

"Private Placement | Issuer"

Common Stock financial

"Securities To Be Sold Common Stock"

Common stock represents ownership shares in a company, giving investors a stake in its success and a say in important decisions through voting rights. It is the most common type of stock traded on markets and can provide income through dividends, as well as potential for value growth. For investors, holding common stock means sharing in the company’s profits and risks.

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 06/23/2026 - 06:14 PM Accepted by SEC EDGAR 06/23/2026 - 06:14 PM 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
Filer CCC
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer

SEC File Number

Address of Issuer

Phone

Name of Person for Whose Account the Securities are To Be Sold

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

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	Merrill Lynch 555 California Street 18th Floor San Francisco CA 94104	1235	122820.75	82257588	06/23/2026	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	03/11/2020	Private Placement	Issuer			1235	03/11/2020	Cash

* 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

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	04/15/2026	2750	247765.57
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	04/22/2026	88	7926.6
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	06/17/2026	92169	8330667.41
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	06/18/2026	100928	9185730.49
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	06/22/2026	243976	24182608.35
Atlas Venture Opportunity Fund I, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	04/15/2026	385	34687.18
Atlas Venture Opportunity Fund I, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	04/22/2026	12	1080.9
Atlas Venture Opportunity Fund I, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	06/17/2026	12902	1166143.4
Atlas Venture Opportunity Fund I, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	06/18/2026	14128	1285827.52
Atlas Venture Opportunity Fund I, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common	06/22/2026	34152	3385105.26
Bruce Booth 300 Technology Sq Ste 8 Cambridge MA 02139	Common	04/14/2026	4159	374199.56
Bruce Booth 300 Technology Sq Ste 8 Cambridge MA 02139	Common	04/15/2026	2200	197895.00
Bruce Booth 300 Technology Sq Ste 8 Cambridge MA 02139	Common	04/22/2026	5900	530746.25
Bruce Booth 300 Technology Sq Ste 8 Cambridge MA 02139	Common	06/17/2026	11741	1056443.24

144: Remarks and Signature

Remarks

Date of Notice

Date of Plan Adoption or Giving of Instruction, If Relying on Rule 10b5-1

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

ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)

FAQ

What does KYMR's Form 144 report?

It reports proposed sales of KYMR common stock by affiliates. The excerpt lists multiple selling entries by Atlas Venture entities and individuals with dated dispositions on 04/15/2026, 06/17/2026, 06/18/2026, and 06/22/2026.

Who are the primary sellers listed in the KYMR excerpt?

Primary sellers include Atlas Venture Fund X, L.P., Atlas Venture Opportunity Fund I, L.P., and Bruce Booth. The entries show multiple share disposals by these holders across April–June 2026 with specific share counts and dollar amounts.

Does Form 144 indicate proceeds go to KYMR (the issuer)?

The excerpt does not state that proceeds go to the issuer. The lines show selling holders and sale dates; cash‑flow treatment is not specified in the provided excerpt and is not attributable here.

What are notable sale examples listed in the filing?

Examples include Atlas Venture Fund X selling 243,976 shares on 06/22/2026 for $24,182,608.35 and Atlas Venture Fund X selling 100,928 shares on 06/18/2026 for $9,185,730.49, per the excerpt.