Huntsman shares slid 7.2% in pre-open trading after the specialty chemicals company revealed an all-stock merger of equals with Olin Corporation that will create OlinHuntsman Corporation. The two companies said the agreement was signed on June 15, 2026 and was disclosed publicly the following morning alongside a joint investor presentation and a Form 8-K filing with the SEC.
Under the terms disclosed, the combined company is expected to deliver about $12.5 billion in combined revenue for 2025 and to realize more than $400 million in identified cost synergies. The structure of the transaction - rather than new operating details - was the principal factor pressuring Huntsman stock in pre-market trading.
Huntsman shareholders will receive 0.5476 Olin shares for each Huntsman share they hold. That exchange ratio was fixed using volume-weighted average prices over the 30 trading days ending June 12, 2026. Because Huntsman had recently reached a 52-week high of $16.09, the implied deal valuation based on current Olin prices sits below that recent peak. The market response - a downward adjustment of HUN toward the implied exchange-value of Olin consideration - is consistent with merger-arbitrage mechanics.
When the transaction closes, existing Olin shareholders will own approximately 54.5% of the combined entity, with Huntsman shareholders holding the remaining 45.5%, a split that reflects Olin's slightly larger weight in the exchange.
Market context highlights the company-specific nature of the move. The S&P 500 was higher by 1.65%, the Nasdaq was up 3.1%, and the Dow Jones Industrial Average had added 0.9% at the same time, indicating a broad risk-on session across most sectors. Against this backdrop, HUN's pre-market decline appears driven by the terms and timeline of the merger rather than by changes in the underlying fundamentals of Huntsman's business.
The transaction remains subject to regulatory approvals and the affirmative votes of shareholders from both companies. The parties are targeting a close in the first half of 2027, leaving multiple quarters of execution and regulatory uncertainty that market participants will weigh as the deal progresses.
Taken together, the early trading reaction reflects investors anchoring Huntsman's share price to the implied value of Olin stock consideration while factoring in the timeline and execution risk inherent in a large cross-company combination in the chemicals sector. Both boards have unanimously endorsed the agreement, but the multi-quarter path to closing and the fixed exchange ratio are central to near-term valuation dynamics for HUN.
Clear summary
Huntsman stock fell in pre-market trading after the company announced an all-stock merger of equals with Olin. The exchange ratio and Huntsman's recent 52-week high produced an implied deal value below that peak, prompting a merger-arbitrage style repricing of HUN even as major indices rallied. The deal must still clear regulatory and shareholder approvals and aims to close in the first half of 2027.