"An experience that might be of interest to other subscribers investing with IG Index

"I recently opened a position with IG Index in China A50 at 9585. I watched the position trade during opening hours and close with a buy price at 9402. Then, with the market closed, the buy price changed to 9103. I took a screen shot of my position (Open at 9585, current buy price 9104, chart showing a close price of 9402) and asked IG Index to look into it. I got this reply when the market reopened.

"The position in question - Xinhua 50 - appears to be fine on your account. The current level is showing as 9570. Please note that we have been experiencing some technical issues with the data feeding through the charts today, which may explain the differences in price. If you still feel that these levels above are incorrect, please feel free to contact us and we will investigate this further. Please accept our apologies for any inconvenience caused."

"So I watched it again yesterday and the same thing happened. It closed with a buy price of 9507, but then the buy price on IG Index changed to 9125.

"I emailed the new screen shot and expressed concern that this irregularity might cause my stop to be triggered incorrectly. I got this reply...

"It is usual that there will be a difference between the closing price on the platform, and the last price shown on the chart. This is because the price on the platform is the price based on the official settlement of that market. However, the price you see on the chart is based on the last price movements before the market closes. The official settlement of a market can often be different to that of the last traded price for an instrument. Hence, there is a difference to the close price on the chart and the close price on the platform. In terms of triggering your stop or limit orders, we will not use the price shown on the chart. All orders are triggered basis the price you see on our platform, which is based off the price in the underlying market."

"Ok - so I understand that but this is a 300 point difference (or 3+%) seems like a lot. Right? I have never noticed this before with other markets. Anyway I have closed out my position as I feel I have no way of knowing where the close value will be and if my stop will be hit."

Eoin Treacy's view Thank you for highlighting this issue. I have also on occasion noticed some variation in pricing quoted after the official close and that quoted during market hours. David and I usually limit our trading to instruments offering access to large liquid contracts. Spread-betting on a fund which is in turn attempting to track an index, such as the China A50, compounds the derivative to a second order of magnitude. The comparative illiquidity of many ETFs is an additional concern. This makes pricing issues more of a threat to one's position but does not reflect the wide variation between the after hours and active markets you cite. Personally, I only tend to utilize such funds when there is no futures market covering the same vehicle.