Trading in Apple shares halted after shock 9pc fall A single trade of 100 shares at a price of $542.80 in the world's most valuable company hit the tape at 10:57 in New York coming from the BATS Exchange. As the previous transaction seconds earlier was at a price of $598.26, a stock circuit breaker rule was triggered and trading was halted. "It looks like a fat finger mistake," Joe Terranova, chief market strategist for Virtus Investment Partners, told CNBC. However, minutes before the trade, BATS sent an alert stating: "Please be advised that BATS is currently investigating system issues trading in symbols range A through BF." The untimely systems glitch occurred on the same day as BATS's stock market debut and also led to erroneous price quotes for the exchange. Hundreds of trades in BATS shares, which floated at $16 a share and fell to $15.25 before the slew of erroneous trades, had to be cancelled after orders seemed to be filled at prices less than a penny a share. The trades were later cancelled by Nasdaq and BATS was forced to declare "self-help," which means an exchange is dealing with internal problems processing trades and needs to send trades through other venues. BATS, headed by 45-year-old Joe Ratterman, was formed in 2005 by major banks and trading firms looking to break the stranglehold that the NYSE and Nasdaq had on US stock trading. Trading in Apple shares have resumed.