Approximately $8 billion in debt securities are affecting a popular investor’s service decision about one of biotech’s biggest. Investing credit rating company Moody’s has affirmed that Monsanto’s new rating is being downgraded from ‘neutral’ to ‘negative’ following Syngenta’s announcement that it has refused Monsanto’s unsolicited bid of CHF449 per Syngenta share in a combination of cash and stock. Monsanto’s offer would have …