German chemical company Bayer will fork over $57 billion to buy American seed seller Monsanto. The all-cash deal — the largest takeover ever by a German company — will create a firm that has control over more than a quarter of the world’s seeds and pesticides.

St. Louis-based Monsanto is infamous both for its genetically modified crops and for being the world’s largest seller of seeds. Bayer, though best known in the US for its aspirin, has a major pesticide division, and also biotechnology, plastics, and health segments.

The two have been in talks since early May. Bayer’s offer is $4 billion more than its initial offer. The $128 per-share price is also up from the original offer of $122 a share. Including debt, the deal is valued at around $66 billion.

John Colley of Warwick Business School told BBC that Bayer’s acquisition could lead to higher prices and be a "horror story" for farmers. The deal could have major political repercussions too: Monsanto has been under fire for years by various anti-GMO protesters and Europe itself is famously anti-GMO.