Shares in TMB Bank Pcl rose in active volume after Kao Hoon newspaper quoted a market source as saying Singapore's state-owned investor Temasek Holdings Pvt Ltd was courting shareholders including ING Groep NV and the Ministry of Finance to buy their stakes in the mid-sized bank.
The acquisition price was expected to be in a range of 2.1-2.5 baht ($0.07-$0.08) per share, the newspaper said.
TMB gained as much as 6.7 percent to 1.76 baht ($0.06), the highest since April 4, with about 421 million shares traded, 4.26 times the average full-day volume over the last 30 sessions.
According to bourse data, the Finance Ministry owns 26.09 percent of TMB while ING holds 25.2 percent plus 5.92 percent through non-voting depository receipts.
Broker Kiatnakin Securities rated the stock a sell, with a target price of 1.56 baht.
"It was a bit about speculation ... There has been no confirmation yet, either from TMB or the Ministry of Finance," the broker said in a report.
Temasek and TMB Bank declined to comment, while the Ministry of Finance was not available for comment.
1356 (0656 GMT)
(Reporting by Viparat Jantraprap and Manunphattr Dhanananphorn in Bangkok; Kevin Lim in Singapore; email@example.com)