Shares in French cancer drugmaker Cellectis struck an all-time high on 29 May on hopes that it will be the latest in a string of bid targets in the healthcare industry.
Shares in Cellectis were trading 10.23% higher at 03.15pm in Paris, after jumping as much as 11%, after the Financial Times reported that the firm was in potential sale talks with a few suitors, including US-based Pfizer.
Pursued by Reuters, a Cellectis spokeswoman said by email that the company does not comment on market rumours. A Pfizer spokesman refused to comment on the takeover talk, which he described as "rumour and speculation".
Pfizer already has a 9.5% stake in the French biotech firm, which it bought when the firms partnered to develop cancer drugs last year.
The French government's Bpifrance sovereign wealth fund holds about 8.7% of Cellectis.
The healthcare sector has seen a historic $240bn (£157bn, €218bn) of deals this year, up 68% on the year-ago period, according to Thomson Reuters data.
In March, Cellectis listed itself on Nasdaq, raising $228m through the sale of American Depository shares.
Cellectis works on Chimeric Antigen Receptor T-cell (or CAR-T) therapy, a cell-based treatment that taps into the body's immune system to battle tumours.