  An investigation of the G-type stellar population with Kepler (as done by
Maehara et al.) shows that less than 1 per cent of those stars show
superflares. Due to the large pixel scale of Kepler ($\sim4 arcsec \:
px^{-1}$), it is still not clear whether the detected superflares really occur
on the G-type stars. Knowing the origin of such large brightenings is important
to study their frequency statistics, which are uncertain due to the low number
of sun-like stars ($T_{eff} = 5600-6000 \:K$ and $P_{rot} > 10 \:d$) which are
currently considered to exhibit superflares. We present a complete Kepler data
analysis of the sun-like stars KIC10524994 and KIC07133671 (the only two stars
within this subsample of solar twins with flare energies larger than $10^{35}$
erg; Maehara et al.), regarding superflare properties and a study about their
origin. We could detect four new superflares within the epoch Maehara et al.
investigated and found 14 superflares in the remaining light curve for
KIC10524994. Astrometric Kepler data of KIC07133671 show that the photocentre
is shifted by 0.006 px or 25 mas during the one detected flare. Hence, the
flare probably originated from another star directed towards the north-east.
This lowers the superflare rate of sun-like stars (and hence the Sun) for $E >
10^{35}$ erg, since this additional star is probably not solar-like.
