The Nasdaq is broken

US stock exchanges halted the trading of all securities on the Nasdaq stock exchange today following reports of a technical issue in the data feed for Nasdaq-listed securities.

The exchange announced the halt at 17:15 (British Summer Time). Other exchanges followed suit and notices of halts in individual securites began from 17:18 in alphabetical order by ticker system. The Nasdaq Composite Index flatlined at 3,631.17, up 0.87 per cent from the previous close.

It was also announced that the Nasdaq had stopped all trading in the options market and advised firms to route all open orders away.

Companies listed on the Nasdaq include Apple, Microsoft, Dell and Cisco. The re-opening time was yet to be confirmed at the time of writing (18:00).

See the Live Blog for more details.