Many mechanisms of antibody diversification have been shown to exist, including combinatorial pairings of heavy and light chains, the use of multiple gene segments (combinatorial diversity), and the imprecise joining of these gene segments (junctional diversity). The contributions of each of these mechanisms to functional antibody activity has not been fully explored, especially in the case of junctional diversity. A chain recombination experiment between an anti-arsonate monoclonal antibody and an anti-oxazolone molecule in which light chains differ essentially only at the V/J junctional position show that junctional diversity may play an important role in antigen binding.