When discussing mergers, both Commission officials and private practitioners often characterise these as a “N to N-1”.  We all regularly talk and hear about “6-to-5s”, “5-to-4s”, “4-to-3s”, “3-to-2s”, and even “2-to-1s”.  This blog discusses the growing view that within the Commission, a “4-to-3 or fewer” distinction has become a corridor-talk presumption of anti-competitive effects.  On…