  A large number of direct imaging surveys for exoplanets have been performed
in recent years, yielding the first directly imaged planets and providing
constraints on the prevalence and distribution of wide planetary systems.
However, like most of the radial velocity ones, these surveys generally focus
on single stars, hence binaries and higher-order multiples have not been
studied to the same level of scrutiny. This motivated the SPOTS (Search for
Planets Orbiting Two Stars) survey, which is an ongoing direct imaging study of
a large sample of close binaries, started with VLT/NACO and now continuing with
VLT/SPHERE. To complement this survey, we have identified the close binary
targets in 24 published direct imaging surveys. Here we present our statistical
analysis of this combined body of data. We analysed a sample of 117 tight
binary systems, using a combined Monte Carlo and Bayesian approach to derive
the expected values of the frequency of companions, for different values of the
companion's semi-major axis. Our analysis suggest that the frequency of
sub-stellar companions in wide orbit is moderately low ($\lesssim $13% with a
best value of 6% at 95% confidence level) and not significantly different
between single stars and tight binaries. One implication of this result is that
the very high frequency of circumbinary planets in wide orbits around
post-common envelope binaries, implied by eclipse timing (up to 90% according
to Zorotovic & Schreiber 2013), can not be uniquely due to planets formed
before the common-envelope phase (first generation planets), supporting instead
the second generation planet formation or a non-Keplerian origin of the timing
variations.
