My only concern is that many indie pirates don't have recognizable names. The STC will be sitting somewhere, publicly announcing (or prompting in conversation) the presence of traders and their names, while some pirate with an inconspicuous name - who STC does not yet recognize as a problem - lies in wait.
The idea of "pirated sighted near..." only works if the pirate stays there for any period of time. Plus, once they know they've been sighted - and necessarily scanned - they'll move.