Eight months after seed leader Monsanto Co. abandoned its $45.2 billion saga to acquire Switzerland’s Syngenta AG, the St. Louis-based agribusiness giant found itself the target of a mammoth takeover bid by a would-be acquirer.

On Monday, Germany’s Bayer AG unveiled a proposal to purchase Monsanto for $62 billion in cash, a potential megadeal that Reuters reported if completed would be the largest all-cash takeover ever. The offer by Bayer, one of the world’s largest life sciences and pharmaceutical companies, represents a 37 percent premium on Monsanto’s closing stock price on May 9.