We have featureclasses on a 10.3 sde database. When I add it to an ArcMap session and try to select multiple objects interactively using the mode mentioned above, it clears the previous selections and just retains the recent selected object. Cannot seem to figure out what the source of the issue is. When I export the dataset to an FGDB the selection is fine. The press "SHIFT" and select does not also work when using SDE featureclass. For tables, no issues selecting or adding to currently selected.
Hope to get some inputs. Thanks.