http://www.alllaw.com/articles/nolo/us-immigration/visa-expires-leave-wait-for-green-card.html
Any immigrant with a pending green card application (for U.S. permanent or conditional residence) is allowed to remain in the United States until the application is decided upon by U.S. Citizenship and Immigration Services (USCIS). However, the key is to understand whether or not you really have a pending green card application. Many people get this wrong and spend time in the U.S. unlawfully, for which there are severe penalties under the U.S. immigration laws.
