• From Reuters: LCH.Clearnet Raises Initial Margin Call on Italian Debt
LCH.Clearnet increased the margin on debt from the [Italy] at a time when its bonds yields are close to levels deemed unsustainable.• European stocks are off today with the FTSE down 2%, and the DAX down 3%.
...
When LCH.Clearnet Ltd took similar action on Portuguese and Irish debt as bond yields soared, it added to selling pressure on the paper. Both countries were later forced to seek bailouts.