Monsanto Said to Make Preliminary $45 Billion Offer for Syngenta

Monsanto Co., the world’s largest seed company, made an initial offer for Syngenta AG valuing its Swiss rival at about $45 billion, people with knowledge of the matter said.

Monsanto offered about 450 Swiss francs per share, the people said, representing a 35 percent premium to Syngenta’s last close. The Basel-based company rejected the offer, though left it open for Monsanto to make another offer or start talks, they said, asking not to be identified as the information is private.