# Mysterious disappearance of options from historical datasets

I am in the process of analyzing historical options data, and I keep finding options that mysteriously disappear before they are due to expire. For example:

For the QQQ $69 Put, http://www.eoddata.com/stockquote/OPRA/QQQ140322P00069000.htm there is no data after 03/11/14 But the QQQ$70 Put,
http://www.eoddata.com/stockquote/OPRA/QQQ140322P00070000.htm
is fine.

It seems that all QQQ Puts with strike below \$70 mysteriously disappears after 03/11/14, despite some of them having significant open interest.

I have found this in a dataset I obtained through another vendor as well.

What is the cause of these disappearances? Is it a data problem or were they halted trading for some reason?

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@Downvoters and closevoters: Please give a reason and/or some ideas how to improve the question - thank you! –  vonjd Jul 2 '14 at 19:14
Can you please use readable dates! 03/11/14 could be 2003-11-14, 2014-11-03 or 2014-03-11. I want to check with my vendor but I don't know what I'm looking for. –  hroptatyr Jul 4 '14 at 6:50