I have an answer here: How to send emails to a users friends when the user takes a specific action?. I posted it months ago and last updated it a week ago (in response to some more info the OP asked for in a comment), so I was surprised to suddenly see four actions on it now:
One unupvote followed 7 minutes later by three simultaneous down votes. About 15 minutes later, the OP also commented on my answer that he is super frustrated now since his script isn't working (for reasons unrelated to my current answer), and he also has an un-rewarded bounty on the question that is ending in less than 24 hours. Also within the last few minutes the OP's post was up-voted.
Now, I'm not saying it's impossible that all of this is just a series of legitimate coincidences, but it does seem highly unlikely. It seems more likely that the OP, in frustration, removed his original upvote and then created some sock puppet accounts to downvote my answer and upvote his question. Of course, my answer is still marked as accepted, so that theory doesn't quite add up. [EDIT: I forgot about the rep requirement for down-voting, so I no longer suspect this is a likely possibility for what happened]. But even if that's not what happened, something fishy seems to be going on here.
Question: For cases like this, should I submit a moderator flag? I don't know if mods have enough information on votes to investigate this any more than I could, or if a flag isn't worth it because this is the kind of thing the automated system will find if it isn't legitimate.