Adjustment of status under section 245(i) is an alternate way to gain permanent residence for eligible immigrants who reside within the United States, but entered the US without inspection. 245(i) also applies to those who originally came to the United States with a visa, but fell out of status and are the spouse of a permanent resident. If you were the beneficiary of a labor certification or visa petition prior to May 2001, you can get a green card through 245(i) by paying a fine and providing additional documentation. The entire process can be completed while you remain in the United States, and does not require consular processing in your home country.
To be eligible for adjustment of status under 245(i), you must have had a visa petition or labor certification filed on your behalf on or before April 30, 2001. Once your are eligible for 245(i), you cannot lose eligibility. This includes if you were a child when your parents filed a visa petition on your behalf, or if you are no longer married to a spouse who filed.
An individual may qualify for adjustment of status under 245(i) if they had a visa petition or a labor certification filed on their behalf by a relative or employer on or before April 30, 2001. The visa petitions include I-130, I-140, I-360, and I-526. The labor certification must have been ETA Form 750 to qualify for 245(i). These petitions must have been "approvable when filed", meaning it was correctly filed and was truthful based on circumstances at the time the petition was filed. The petition did not have to be approved by April 30, 2001, but it must have been filed by that date. To get proof of old petitions, the best way is to file a Freedom of Information Act (FOIA) request.