Expected mean number of companions per quasar with proper transverse separation ﹩5\ h^{-1}\ \mathrm{kpc}\,< R_{\mathrm{prop}\,}< 50\ h^{-1}\ \mathrm{kpc}\,﹩ and velocity difference ﹩\vert \Delta v\vert < 2000\ \mathrm{km}\,\ \mathrm{s}\,^{-1}﹩, as a function of redshift calculated from eq. [16], which assumes that the large‐scale quasar correlation function can be extrapolated as a power law to small scales. We used the correlation function parameters ﹩\gamma =1.53﹩ and ﹩r_{0}=4.8\ h^{-1}\ \mathrm{Mpc}\,﹩ measured by PMN04 from the 2dF quasar survey. A perfect survey, with no sources of incompleteness, is assumed. In a sample of ~50,000 quasars, the predicted number of binaries with ﹩5\ h^{-1}\ \mathrm{kpc}\,< R< 50\ h^{-1}\ \mathrm{kpc}\,﹩ is ~1. However, our clustering sample already contains 20 quasars with transverse separations this small, which is compelling evidence for excess clustering over what is expected from extrapolating the correlation function.