After doing 3 of the Borg Ground Invasion, it's become apparant that there needs to be Anti-Theft protocols similar to the ones implemented with the Academy Events.

1. Prevent people from kill-stealing your Borg kills outside of groups.
   
2. Waiting for people to clear or engage mobs in order to get an easy scan. (Which is most of the Medium Difficulty Missions).

Actually, I don't believe this is needed. You don't even need to group up, and you still get credit for most things other do. There are a few exceptions, so instead of doing some kind of complicated prevention/tagging, all cryptic should do is fix those missions so everyone nearby gets credit, and all will be well. Mainly this goes for the City Rescue Defari from houses mission

Or, If you're talking about the medium temple missions, instead of trying to solo them, group up.It's harder to steal kills from a group (few people shoot, one does the clicking, works the same as someone trying to 'steal the click')

Overall, I haven't seen much of an issue