Shares of Monsanto rose more than 8 percent Thursday after reports that two German firms were interested buying the agrochemical company.
Bloomberg reported that Bayer is exploring a potential bid for Monsanto, citing people familiar with the matter, while multiple reports said BASF was is working with investment banks on another bid.
Bayer and BASF declined to comment. Monsanto did not immediately respond to CNBC's comment request.
At Thursday's close, Monsanto shares were down 0.6 percent year to date and 15.6 percent lower in the past 12 months.
MON in past year
On Thursday, however, Monsanto's stock was tracking for its best day since Jan. 7, 2009.