Under review. 

Previous title was "Financial Incentives for US Corporate Green Bonds." 

Abstract: We develop and test a dynamic signaling model of labeled-bond pricing using U.S. corporate green and sustainability bonds matched to the same-issuer conventional debt. The benefit accrues mainly through underwriting fees, not risk-adjusted yields, concentrated at debut. Green's yield discount does not survive Treasury-netting; only seasoned sustainability earns a risk-adjusted one. Inaugural issuance raises disclosure without improving performance. Returning to conventional debt, sustainability histories raise yields and green histories raise fees, turning the premium into a penalty. This asymmetry reflects claim verifiability and clientele demand: verifiability lowers the credibility-risk premium investors require but raises the relationship franchise underwriters later monetize.