Moving feature classes between FGDB's creates unknown topology errors [closed]

I am attempting to merge together multiple large feature classes from different FDGB’s into a single feature class and am getting unknown topology errors when checking for gap and overlap rules. I have run topology checks on these feature classes before and the layers are clean, however for some reason when I merge the different datasets together the resolution of the features seems to diminish and create topology errors that weren’t there prior to the merge. I am thinking this could be an issue caused by geoprocessing the feature classes from different FDGB’s but can’t confirm this is true. Any ideas on issues that may be causing this would be extremely helpful. I am running ArcMap 10.2 with 64 bit processing.