Liquidity as a choice variable: a lesson from the Japanese government bond market

In Japan, almost identical government bonds can trade at largeprice differentials. Motivated by this phenomenon, we examinethe issue of the value of liquidity in markets for risklesssecurities. We develop a model of an issuer of bonds, a marketmaker, and heterogeneous investors trading in an incompletemarket. We show not only that divergent prices for similar securitiescan be sustained in a rational expectations equilibrium butalso that this divergence may be optimal from the perspectiveof the issuer. Price segmentation is possible because agentshave a desire to trade, but short-sale restrictions limit theirtrading strategies and prevent them from forcing bond pricesto be equal. Restricting the form of market making to excludeprice competition and unregulated profit maximization is alsonecessary to sustain price segmentation. The optimality of segmentationfrom the issuer's standpoint arises because of the issuer'sability to charge for the liquidity services provided to theinvestors.