
Ask HN: Can you “sell” more Bitcoin than you actually own? - libertylocked
Say I run a wallet service where users can buy bitcoins from me and keep them in their &quot;online wallet&quot;. When a user clicks &quot;buy&quot;, do I have to actually buy bitcoins for the user?<p>Or can I just simply update my database to increment their balance when a user clicks &quot;buy&quot;?<p>What happens if I try to &quot;sell&quot; more Bitcoins than I own? For a service like Coinbase, is there a way for them to prove that they actually have the bitcoins for a user?
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PaulHoule
Like short selling?

