I don’t think the emphasis should be on transfer, but on the contingency of transfer. In order for a transaction to be part of a market, as opposed to theft or other non-market transfer, the participants must have the choice NOT to make the transfer, if the exchange is not acceptable.
There are lots of variants and levels of optionality, leading to legitimate debates about “how much is this a market, vs a coerced behavior”. But the core of markets and analyses of how they behave is that they are, on some scale and timeframe, voluntary.
I don’t think the emphasis should be on transfer, but on the contingency of transfer. In order for a transaction to be part of a market, as opposed to theft or other non-market transfer, the participants must have the choice NOT to make the transfer, if the exchange is not acceptable.
There are lots of variants and levels of optionality, leading to legitimate debates about “how much is this a market, vs a coerced behavior”. But the core of markets and analyses of how they behave is that they are, on some scale and timeframe, voluntary.