LSE close hit by technical glitch
LSE clients were worried the slight delay might have meant that orders destined for the auction were mixed with normal trades, triggering concerns over which trades had been executed.
"Normal trading overran into what we thought was the auction so we didn't know what was going on for a while," said the head of electronic trading at one European broker.
The LSE, which said all trades would remain valid, added it was investigating the problem.
(Reporting by Luke Jeffs; Editing by Jon Loades-Carter)