Bayer AG's (BAYN) $66 billion takeover of Monsanto (MON) may not happen until early 2018 as the company has asked European regulators to extend their investigation deadline by 10 extra working days to provide "an appropriate evaluation given the size of the transaction."

The European Commission's investigation into the matter only began last month and was birthed of fears that the merger could damage European farmers' ability to seek out new and higher quality products at competitive prices. "Seeds and pesticide products are essential for farmers and ultimately consumers," said commissioner Margrethe Vestager in a statement. 

The deal also follows Dow Chemical's (DOW) $130 billion merger with DuPont (DD - Get Report)  and ChemChina's $43 billion takeover of Syngenta AG. In both the previous mergers, assets had to be sold before they were cleared by the EU.

If the EU approves Bayer's requested extension, it will push the deadline to January 22, 2018, meaning the deal isn't likely to close until much later than earlier predictions. 

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