In Werner Baumann's world, the truth is one-dimensional, as he likes to put it, based on facts and scientific findings, studies and expert opinions. That's why the head of Germany's Bayer Group has no doubts about the safety of glyphosate. He says he would acquire Monsanto, the American manufacturer of the controversial crop herbicide at any time, "without any ifs, ands or buts."

But the world outside Bayer Group views things differently. A large segment of the public considers glyphosate to be toxic and Monsanto itself to be the epitome of evil. Thousands of farmers with cancer have filed lawsuits against Monsanto's new owner, and investors now view Bayer shares as high-risk stocks they don't want to include in their portfolios. This has made the past year one of the most difficult in Bayer Group's 155-year history. The new year could prove to be even more turbulent, and it's possible the situation could grow even more perilous for the company.