  Trojans are small bodies in planetary Lagrangian points. In our solar system,
Jupiter has the largest number of such companions. Their existence is assumed
for exoplanetary systems as well, but none has been found so far. We present an
analysis by super-stacking $\sim4\times10^4$ Kepler planets with a total of
$\sim9\times10^5$ transits, searching for an average trojan transit dip. Our
result gives an upper limit to the average Trojan transiting area (per planet)
corresponding to one body of radius $<460$km at $2\sigma$ confidence. We find a
significant Trojan-like signal in a sub-sample for planets with more (or
larger) Trojans for periods $>$60 days. Our tentative results can and should be
checked with improved data from future missions like PLATO2.0, and can guide
planetary formation theories.
