Shares of Monsanto Co. are surging Thursday after Bloomberg News reported Germany’s Bayer is exploring a bid for the U.S. seed company.

State-owned ChemChina’s proposed acquisition of Syngenta and a potential merger of Dow Chemical and DuPont has dramatically changed the agricultural landscape in a matter of months.

Valued at about $40 billion at the market close Wednesday, Monsanto made a bid for Syngenta last year.

Monsanto’s shares were up 9 percent at $98 while Bayer’s shares were down 4 percent.

Both Monsanto and Bayer declined to comment on the Bloomberg News report, which cited people familiar with the matter.

Monsanto has long argued it needs to buy or team up with a large crop chemicals maker because farmers will increasingly look for one-stop shops offering seeds, pesticides and digital services such as satellite-guided spraying and harvesting.

Bloomberg reported in March that Monsanto has been in contact with both Bayer and Germany’s BASF about deals in agricultural chemicals.

Citing sources, reported late Wednesday that BASF was considering a bid for Monsanto. BASF, whose shares were down slightly at 68.15 euros, declined to comment.

If Bayer goes ahead with a bid, it would raise pressure on BASF to consider an offer, Bloomberg said Thursday, again citing people familiar with the matter.

But those sources told Bloomberg no decision had been made and that Bayer could decide against a bid or to pursue other transactions with Monsanto, including asset sales or joint ventures.

Data from Reuters were used to report this story.