Oxford BioMedica PLC (LSE:OXB) shares climbed over 11% to 895p after revealing that it has received an unsolicited approach from Stockholm-listed investor EQT about a possible cash offer.
A statement was issued by the board after markets closed on Wednesday to confirm recent press speculation and share price movement, which had seen the shares climb over 30% since the start of the year and over 15% on Wednesday.
"Preliminary discussions" are underway between the two parties, it said, "to explore whether a proposal can be made at a level that the board would be minded to recommend".
The discussions follow earlier unsolicited proposals from EQT regarding a possible acquisition, which the OXB board said it rejected them on the basis that they undervalued OXB and its prospects.
While it has now decided to enter talks, the company stressed that there is no certainty that any firm offer will be made.
EQT's put-up-or-shut-up deadline is 5pm on 11 February.