The overall shape of the k obs vs. [I] 0 plot under tight-binding experimental conditions is neither linear nor hyperbolic, as is always the case in the absence of inhibitor depletion. Instead, the tight-binding k obs plot has a relatively complex shape, generally concave upward, in many cases even including a local minimum. If inhibitor depletion is in fact prominent, the k obs vs. [I] 0 data actually includes information about the concentration of the enzyme active sites.