A fiance (fiancee) holding K1 visa will receive a conditional green card, if at time of approval the marriage is less than two years old. K3 spouses and job-creation investors also receive conditional green cards.
A K1 visa holder will receive a "conditional" green card, if at the time of I-485 approval their marriage is less than two years old. What it means is that the non-citizen spouse's permanent resident status is granted on condition of a bona fide marriage with a U.S. citizen. It is a temporary green card, designed to fight against marriage fraud.
A conditional green card is valid for two years only, and will expire if the condition is not removed. The non-citizen spouse will lose his/her lawful permanent resident status if a conditional green card expires. As a comparison, a regular green card is valid for 10 years. And although the card itself still expires after 10 years, the holder's lawful permanent resident (LPR) status doesn't.
If you are granted a conditional green card when your marriage is almost two years old, you still have to wait two years to remove the conditions - it doesn't truncate. For example, a non-citizen spouse who received her conditional green card 1.5 years after getting married still has to wait 2 more years, not half a year, to remove the conditions on your residence.
If you are still married, you and your citizen spouse must jointly file Form I-751, Petition to Remove Conditions on Residence, during the 90 days immediately before the expiration date of your conditional green card.
If you don't file I-751, you will lose your permanent resident status as soon as your conditional green card expires. At that point you will become deportable from the United States.
If you file I-751 late, you must demonstrate that the delay was due to extraordinary circumstances beyond your control and that the length of the delay was reasonable.
You may apply for a waiver to the joint filing requirements if:
If you file I-751 with a request to waive the joint filing requirement due to any of the above reasons, you may file the petition at any time after you receive the conditional green card and before you are removed.
USCIS memo, dated April 3, 2009 provides guidance on I-751 filed prior to termination of marriage. This important memo offers relief to conditional permanent residents who have initiated divorce or annulment proceedings, but the marriage has not been terminated.