Kronos Bio, Inc. SEC Filings

Kronos Bio (NASDAQ: KRON) has received a Notice of Effectiveness from the SEC on June 23, 2025 for their POS AM (Post-Effective Amendment) filing. The amendment relates to Registration Statement File Number 333-283072.

A Post-Effective Amendment becomes effective when the SEC issues a notice of effectiveness, allowing the company to proceed with the amended registration statement. This filing indicates that Kronos Bio's previously filed registration statement modifications have been reviewed and approved by the SEC.

This administrative filing is a routine regulatory matter that confirms the effectiveness of Kronos Bio's amended registration statement, which may relate to securities offerings, equity compensation plans, or other registered securities.

Kronos Bio, Inc. (NASDAQ: KRON) filed five Post-Effective Amendments to previously effective Form S-8 registration statements in order to deregister all unsold shares that had been reserved for issuance under the company’s 2017 Equity Incentive Plan, 2020 Equity Incentive Plan, and 2020 Employee Stock Purchase Plan.

The administrative action follows the closing of the June 20, 2025 merger in which Concentra Merger Sub IV, Inc., a wholly-owned subsidiary of Concentra Biosciences, LLC, merged with and into Kronos Bio. Each outstanding common share was converted into the right to receive $0.57 in cash plus one non-transferable contingent value right (CVR). As Kronos now operates as a wholly-owned subsidiary of Concentra, all public offerings under the referenced S-8 statements have been terminated in accordance with prior undertakings, and the effectiveness of the statements has been withdrawn.

The filing is purely procedural: it eliminates the registration of roughly 34 million shares that remained unissued across the five plans, confirms that no additional equity will be issued, and finalises the company’s transition away from public-company status.

On 20 June 2025, Kronos Bio, Inc. (KRON) submitted five Post-Effective Amendment No. 1 filings to its prior Form S-8 registration statements, formally deregistering all remaining unissued shares tied to the company’s employee equity plans. The amendments cover the 2017 Equity Incentive Plan, the 2020 Equity Incentive Plan and the 2020 Employee Stock Purchase Plan, which together had originally registered more than 17 million shares across filings 333-249424, 333-254620, 333-262993, 333-270564 and 333-278125.

The clean-up filing follows the completion of the previously announced merger with Concentra Biosciences. Effective the same day, Concentra Merger Sub IV merged into Kronos, leaving Kronos as a wholly owned subsidiary. Each outstanding KRON common share—except those held in treasury, by the buyer or by dissenting holders—was converted into the right to receive $0.57 in cash plus one non-transferable contingent value right (CVR).

Because the merger terminates any future issuances under the equity plans, Kronos has ended the related securities offerings and removed any unsold securities from registration, satisfying its undertaking under Rule 415. The filing is largely administrative, eliminates potential dilution from unused plan shares and confirms that KRON equity no longer trades publicly.

Kronos Bio, Inc. (NASDAQ: KRON) filed five Post-Effective Amendment No. 1 filings to previously effective Form S-8 registration statements on 20 June 2025. The purpose is to deregister all unsold shares that had been reserved for issuance under the 2017 Equity Incentive Plan, the 2020 Equity Incentive Plan and the 2020 Employee Stock Purchase Plan.

The amendments follow the closing of the cash acquisition by Concentra Biosciences, LLC. Under the 1 May 2025 Agreement and Plan of Merger, completed on 20 June 2025, each outstanding Kronos share was converted into the right to receive $0.57 in cash plus one non-transferable contingent value right (CVR). With the merger consummated, Kronos has terminated all public offerings of its securities and is removing from registration every share that remains unissued under the five S-8 statements (originally covering millions of shares across the three plans).

As required by Rule 478 and the undertakings in each S-8, the filing formally ends the effectiveness of the registration statements, eliminating ongoing Exchange Act compliance obligations tied to those employee equity programs. The document is signed solely by Chief Financial Officer Michael Hearne pursuant to Securities Act Rule 478, reflecting Kronos’ new status as a wholly owned subsidiary and its exit from the public markets.