H.I.S., already Unizo's top shareholder with a 4.79% stake, said it would offer 3,100 yen for each Unizo share, representing a 56% premium over Tuesday's closing price of 1,990 yen.

Shares in Unizo rose by the daily allowable limit of 400 yen ($3.67), or up 20%, after the Nikkei business daily reported the possible deal earlier. H.I.S. shares fell as much as 6.3% before ending down 4.6%.

(Reporting by Chang-Ran Kim; Editing by Himani Sarkar)