We test the no-trade theorem in a laboratory financial market where subjects can trade an asset whose value is unknown. Subjects receive clues on the asset value and then set a bid and an ask at which they are willing to buy or to sell from the other participants. In treatments with no gains...

We analyze the incidence and welfare effects of unit sales taxes in experimental monopoly and Bertrand markets. We find, in line with economic theory, that firms with no market power are able to shift a high share of a tax burden on to consumers, independent of whether buyers are automated or...