The reason is that GE has traditionally been one of the biggest issuers of Commercial Paper to fund daily operations, and used to be one of the biggest issuers of the debt: veteran readers may recall that during the financial crisis, GE's loss of access to the frozen CP/Money Market nearly resulting in a terminal liquidity crisis at the industrial conglomerate.

Since then, GE's reliance on commercial paper was material, and in the second quarter, GE had on average around $16.6 billion of the debt outstanding - a sizable portion of its total $116 billion in debt.

A warning shot came in early October, when S&P cut GE's short-term grade to A-2, a level below the top tier. That's a rating of commercial paper that some classic prime money market funds are reluctant to buy. In fact, prime money market funds historically had to have at least 97% of their securities rated at least A-1 from S&P and P-1 from Moody's, but those rules were loosened amid this decade's money market reform. Even so, as Bloomberg noted, many funds would be far less willing to buy securities with a split rating, i.e., where at least one rating is below A-1 or P-1.