Isotropic energy emitted in the observer 0.3−10 keV energy band vs. rest frame peak time for the sample of late-time flares (blue squares) compared with the early-time flare sample (red stars). The absence of energetic late-time flares is manifest. Inset: distribution of the logarithm of the isotropic energy emitted in the 0.3−10 keV energy band of late-time flares (blue rectangles) compared with the early-time flare one (red rectangles). The late-time flares are clearly less energetic than the early-time ones, with a median for the distribution of the energy 1.4 × 10⁵⁰ erg and standard deviation σ = 3.2 × 10⁵⁰ erg.