
What is the difference between “conditional” and “unconditional” green cards?
A conditional green card is a provisional visa that is valid for just two years. This is the visa first granted to an EB-5 investor who is approved for EB-5 immigration under the regulations of the US Citizenship and Immigration Services. You need to apply for removal of the conditions before the visa expires. Once all investment and residency requirements are met, the Citizenship and Immigration Services will grant the unconditional green card. The unconditional green card is a permanent resident visa that is no longer contingent on your investment. Apart from the expiration date and the conditions both green cards will grant you the same rights and privileges.
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