  In this paper, we present an algorithm to correct optical light curves
obtained using The Zwicky Transient Facility Forced Photometry Service and its
application to the analysis of optical variability of 136 actvie galactic
nuclei (AGN) powered by "light-weight" supermassive black holes (SMBH;
$M_{BH}$<2*10^6 $\odot$) including 24 intermediate-mass black holes (IMBH;
$M_{BH}$<2*10^5 $\odot$). We detected variability in nearly all sources and
also analyzed its dependence on the X-ray luminosity for 101 objects. We also
identified a previously unknown candidate tidal disruption event (TDE) in
SDSS~J112637.74+513423.0.
