US agricultural equipment manufacturer Monsanto challenged the rulings of two court cases that found its chemical Roundup to have caused cancer in two men . Two subsequent court cases , eight years apart , have concurred that glyphosate in the product was a " substantial factor " in causing cancer in two men , but the Bayer - owned company has claimed that the science used was flawed . The evidence presented , such as the International Agency for Research on Cancer 's assessment , that was considered to be " proof " by two juries does not equate to a scientific proof , the firm 's lawyers have said .
US agricultural product manufacturer Monsanto disputes the rulings of two court cases that found its weedkiller Roundup to have caused cancer in two plaintiffs. Two US court cases, eight months apart, have concurred that glyphosate in the product was a "substantial factor" in causing cancer in two men, but the Bayer-owned company has claimed that the science used was flawed. The evidence presented, such as the International Agency for Research on Cancer's assessment, that was considered to be "proof" by two juries does not equate to a scientific proof, the firm's lawyers have said.