Ambipar Emergency Response (AMBI)

Ambipar Emergency Response is a Brazil-based provider of environmental emergency response services. The business traces its roots to 2009 and is headquartered in São Paulo. It operates as part of the Ambipar group, a Brazilian environmental services conglomerate controlled through Ambipar Participações e Empreendimentos S.A., which remained the controlling shareholder of the emergency response business.

The company's core activity is preparing for and responding to environmental and industrial emergencies. Its services include emergency prevention and training, response to oil spills, chemical accidents and other pollutant releases, and response to natural disasters such as hurricanes and floods. It also provides specialized industrial cleaning and related compliance support. Customers include operators in sectors such as highways, railways, airports, ports, mining and pipelines, and the group expanded beyond Brazil through acquisitions in North America, Europe and other regions.

Ambipar Emergency Response reached the U.S. public markets in 2023 through a business combination with HPX Corp., a special purpose acquisition company. Following that transaction, its ordinary shares and warrants were listed on the NYSE American under the symbols AMBI and AMBI-WT. As a foreign private issuer, the company reported to the SEC on Form 6-K and Form 20-F rather than the domestic forms used by most U.S. issuers.

During 2025 the wider Ambipar group faced pressure related to its debt load and the cost of financing, which drew attention to the parent company's creditors and its restructuring efforts. The emergency response unit, which had issued its own notes in the international markets, was closely tied to the group's financial position through ownership and shared management.

On October 22, 2025, NYSE American announced that its staff had determined to commence proceedings to delist the company's common shares and warrants from the exchange. The notice was published through a Business Wire release, and the company had the right to request a review of the determination under exchange rules.

On October 28, 2025, NYSE American announced that it was suspending trading in Ambipar Emergency Response's securities immediately, and the exchange moved to remove the securities from listing and registration by filing a Form 25 with the SEC. The Form 25 covered both the ordinary shares (AMBI) and the warrants (AMBI-WT). The delisting was an exchange-initiated action, not an acquisition or a voluntary withdrawal by the company, and no purchase price or successor entity was involved.

After the suspension, the securities were no longer eligible for trading on a U.S. national securities exchange. Shareholders holding the shares at that time continued to own them, but any further trading would have to take place on an over-the-counter market or another venue, if at all.