S&P circuit breakers triggered

The Washington Post activated the S&P 500 circuit breakers for the first time yesterday after its shares doubled in price within the space of one second. The safety catches, brought in after last month’s “flash crash”, freeze a stock if its price rises or falls by 10 per cent inside a period of five minutes. Washington Post paper was trading at $460 yesterday afternoon when two orders were executed at $919.2, followed by another at $929.2. A spokesperson for the New York Stock Exchange Euronext platform confirmed the three trades were erroneous and said it was investigating.