Daiho Construction, the Tokyo-listed civil engineering group known for shield-tunneling and pneumatic caisson work, is buying its way into a regional infrastructure roll-up in Japan's Tohoku region. The company's board resolved on August 25, 2026 to acquire 1,682,133 shares of UNICON Holdings, equal to 17.00% of the Sendai-based company's voting rights, from private equity seller Endeavor United No.2 Investment Limited Partnership. The shares change hands off-market at a price neither company will disclose, citing the seller's wishes and mutual confidentiality obligations.
The transaction reshuffles UNICON's ownership without touching its balance sheet. UNICON is not issuing new shares or disposing of treasury stock, and it is not even a party to the share-transfer contract between Endeavor United and Daiho. Endeavor United's stake falls from 40.01% to 23.00% of voting rights, but it remains UNICON's largest shareholder. Daiho becomes the second-largest, ahead of every other holder on the register.
| Shareholder | Stake before | Stake after |
|---|---|---|
| Endeavor United No.2 Investment LPS | 40.01% (No. 1) | 23.00% (No. 1) |
| Daiho Construction | Not a shareholder | 17.00% (No. 2) |
Daiho will get a board seat as part of the arrangement, but not automatically: UNICON says it will put a Daiho-nominated director candidate to a vote at its eighth annual shareholders' meeting on September 29, 2026. Because the purchase pushes Daiho's holding past 5% of voting rights, the acquisition also counts as an "accumulation act" under Article 167 of Japan's Financial Instruments and Exchange Act, the rule that treats large off-market share grabs similarly to a quasi-tender offer even without a public bid.
The two companies frame the tie-up as a value-chain match: Daiho's tunnel and caisson construction technology paired with UNICON's maintenance and inspection platform across Yamagata, Fukushima and Miyagi prefectures. Their alliance agreement lists five joint work areas: combining technical know-how to win more contracts, joint bids on public-private infrastructure (PPP/PFI) projects, pooling construction networks and staff, joint training and digital-tools programs, and shared M&A deal flow and co-investment. A "business alliance committee," still informally named, will work out the specifics.
The numbers behind the deal show why both sides want the partnership. Daiho's revenue slipped from ¥163.2bn to ¥139.8bn over the three years to March 2026, but its bottom line recovered from a ¥2.07bn net loss to a ¥4.56bn profit over the same period. UNICON, whose fiscal year ends in June, grew sales from ¥15.6bn to ¥18.8bn but saw net income slip to ¥985mn in the year to June 2026 from ¥1.12bn the year before.
Settlement of the share purchase is set for August 26, 2026, with the ownership change formally completing on August 31. Daiho called the impact on its earnings "minor," while UNICON said the effect on its own current-year results is still under review.