There were some odd simultaneous selling events today. Stocks, corn and soybeans got hit around noon. Then around 2 PM EST stocks, gold & oil got hit.
I wonder if some big beefers got margin calls & liquidated? Bloomberg said some stocks were being hit with big blocks. Some were not larege weights in the S&P, so probably not program trades or asset allocations. One was CVS. So I suspect beefer liquidations.