Has that ever happened?
Some have these KYC.
Will it happens?
In most exchanges I go anonymous. On some I got some money.
Hell YES, there is a new rule just published, ALL Exchanged on USA SOIL Must divulge all sales over $20k to the IRS
U will then get an automatic bill from the IRS for not declaring this un-earned income, and all penalty's are DUE,
All exchanges on USA soil to be licensed, and conditions are licensing are being a compliant agent for the IRS, in other words all BTC exchanges on USA soil, are IRS tax collectors and enforcers.
The $20k rule will eventually drop to $10k, and goal is $500 USD all sales of crypt to be reported to IRS
[ zog? usa, austrailia, japan, taiwan, so-korea, uk,can, .. all usa colonys areas held by usa military under zog ]
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Summary, never use a exchange that is under ZOG, that means probably only safe exchanges be china and/or russia
IRS like FBI are just ZOG agents keeping the funds flowing to Tel-Aviv(City of London), since 1913 FRB