More than 20 years ago, B. Fischer [5,6] started his pioneering work on groups generated by a conjugacy class of 3-transpositions, i.e., a conjugacy class of involutions D, such that for all d, e ∈ D, we have that [d, e] = 1 or 〈d, e〉 ' SL2(2). Fischer classified all finite groups G generated by a class of 3-transpositions under the additional assumptions that G′′ = G′ and O2(G) = O3(G) = Z(G) ...