The main idea is that non-spherical objects have different light curve signatures and should be distinguishable from the usual patterns of a transiting planet.
Because hundreds or thousands of people are now looking at light curves via the Planet Hunters project, I thought it’s a good idea to post what the paper says about unusual light-curve patterns that might be caused by the transit of artificial planet-sized objects. Who knows? Perhaps the common folk hunting for planets might end up finding Civilizations as well!
So, dear planet-hunter slash civilization-hunter, start familiarizing yourself with the sample patterns I compiled below (as a quick reference) while you're classifiying light curves at PlanetHunters.org. Good luck with spotting that Kardashev Type II Civilization !!!
* TLC Mechanics/Dynamics, A sub-field of the science of planet-hunting focused on the study and analysis of Transit Light Curves