Content Type Nodes Automatically Update

Hi,

After using Node Export to Import nodes into a site, the Content Type nodes imported seem to update every time crone runs...

So every day, the nodes of this particular content type are updated and are put at the very top of the list on the content page. Totally baffled as to how to fix this. Not sure if it's a bug or if I forgot something.

Any suggestions would be much appreciated.

Ronen