---
title: "Keystone Acquisition Raises $287.5M IPO; Signs Warrant, Trust and Related Agreements"
type: "News"
locale: "en"
url: "https://longbridge.com/en/news/289095960.md"
description: "Keystone Acquisition completed a $287.5 million IPO, including full over-allotment exercise, and executed multiple agreements to support SPAC operations. Proceeds were deposited into a trust administered by Efficiency. The company signed warrant, registration rights, administrative, and lock-up agreements with its sponsor and underwriters (Cohen & Company, Clear Street) to protect shareholders, define rights, and ensure liquidity post-combination."
datetime: "2026-06-08T19:43:01.000Z"
locales:
  - [zh-CN](https://longbridge.com/zh-CN/news/289095960.md)
  - [en](https://longbridge.com/en/news/289095960.md)
  - [zh-HK](https://longbridge.com/zh-HK/news/289095960.md)
---

# Keystone Acquisition Raises $287.5M IPO; Signs Warrant, Trust and Related Agreements

Keystone Acquisition completed a $287.5 million IPO of 28,750,000 units, including full exercise of the over-allotment, and executed a suite of agreements to support the offering and SPAC operations. The company deposited $288,218,750 of IPO and private placement proceeds into a U.S.-based trust administered by Efficiency. It also entered warrant, registration rights, administrative, letter, and private placement agreements with its sponsor and the underwriters’ representatives. These steps are intended to protect public shareholders, define warrantholder rights, and provide liquidity pathways after a future business combination.

**Agreement 1: Keystone Acquisition Finalizes $287.5 Million IPO Underwriting With Cohen & Company, Clear Street**

-   **Agreement type**: Underwriting Agreement for initial public offering
-   **Counterparty**: Cohen & Company Capital Markets and Clear Street
-   **Signed / Effective**: Jun 02 2026 / same
-   **Duration / Termination**: Through IPO closing and customary post-closing obligations
-   **Reason**: Facilitate and distribute $287.5 million IPO

**Agreement 2: Keystone Acquisition Enters Warrant Agreement With Efficiency to Govern IPO Warrants**

-   **Agreement type**: Warrant Agreement
-   **Counterparty**: Efficiency
-   **Signed / Effective**: Jun 02 2026 / same
-   **Duration / Termination**: Until warrant expiration per terms
-   **Reason**: Administer public and private warrants

**Agreement 3: Keystone Acquisition Adopts Letter Agreement Setting Lock-Ups for Directors, Officers and Sponsor**

-   **Agreement type**: Letter Agreement (lock-up and related covenants)
-   **Counterparty**: Executive officers, directors, advisors and Keystone International Acquisition Management
-   **Signed / Effective**: Jun 02 2026 / same
-   **Duration / Termination**: Until business combination and specified periods thereafter
-   **Reason**: Establish lock-ups and align stakeholders for IPO

**Agreement 4: Keystone Acquisition Establishes Trust Agreement With Efficiency to Hold $288.2 Million IPO Proceeds**

-   **Agreement type**: Investment Management Trust Agreement
-   **Counterparty**: Efficiency
-   **Signed / Effective**: Jun 02 2026 / same
-   **Duration / Termination**: Until business combination or liquidation
-   **Reason**: Safeguard IPO proceeds in U.S.-based trust

**Agreement 5: Keystone Acquisition Signs Registration Rights Agreement for Sponsor and Holders**

-   **Agreement type**: Registration Rights Agreement
-   **Counterparty**: Sponsor and other holders
-   **Signed / Effective**: Jun 02 2026 / same
-   **Duration / Termination**: Post-business combination per terms
-   **Reason**: Provide resale registration after business combination

**Agreement 6: Keystone Acquisition Sells 5.59M Private Placement Warrants to Sponsor for $5.59 Million**

-   **Agreement type**: Private Placement Warrants Purchase Agreement
-   **Counterparty**: Keystone International Acquisition Management
-   **Signed / Effective**: Jun 02 2026 / same
-   **Reason**: Sell 5,593,750 warrants to fund offering costs

**Agreement 7: Keystone Acquisition Sells 2.88M Private Placement Warrants to Underwriters for $2.88 Million**

-   **Agreement type**: Private Placement Warrants Purchase Agreement
-   **Counterparty**: Cohen & Company Capital Markets and Clear Street
-   **Signed / Effective**: Jun 02 2026 / same
-   **Reason**: Sell 2,875,000 warrants to underwriters' designees

**Agreement 8: Keystone Acquisition Enters Administrative Services and Indemnification Agreement With Sponsor**

-   **Agreement type**: Administrative Services and Indemnification Agreement
-   **Counterparty**: Keystone International Acquisition Management
-   **Signed / Effective**: Jun 02 2026 / same
-   **Reason**: Provide office, administrative support and indemnification

Original SEC Filing: Keystone Acquisition Corp. \[ KEYYU \] - 8-K - Jun. 08, 2026

**Disclaimer**

This is an AI-powered summary. It may contain inaccuracies. Consider verifying important information with the source. Please note this summary is solely based on documents filed with the SEC.

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