On a known and trusted exchange like Coinbase, Gemini, or Kraken — yes, it is safe . They have to gather identification documents to be in compliance with AML/KYC laws in the US, the same as a bank would verify your identity if you were physically present to open an account.
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Certain deposits, such as first time ACH purchases, credit or debit card purchases or digital wallet purchases will trigger a temporary (72 hour) withdrawal hold on the account, for security purposes. The below instructions show how to make a withdrawal via the Kraken.com site.
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