The Legal-eaze website provides excellent information concering readoption. The following document can be found here

Readoption -- The Advantages

As many of you already know, there is an enormous amount of red tape among governmental
offices in the U.S. For instance, most states recognize foreign adoption decrees as final. However, USCIS (U.S.Citizenship and Immigration Services, formerly BCIS and INS) only recognizes some, and not all.

To understand this, you must understand visas.
An IR3 visa means that the child has been classified as an immediate relative (hence “IR”) and
was physically seen by all of his/her parents before the adoption took place.
An IR4 visa means that the child was not physically seen by all of his/her parents before the
adoption took place.
While most states recognize the foreign adoption as final, USCIS does not recognize the adoptionof IR4 visa entrants as full and final. USCIS requires that a readoption be completed in the child’shome state before it will recognize the adoption as final. Therefore, it is mandatory that all IR4visa children be readopted. Once the readoption is finalized, the child is now a U.S. citizen. Yournext step is to obtain a Certificate of Citizenship.

Why, then, is it recommended for children entering the U.S. under IR3 visas to be readopted?
Here is where the red tape comes fully into play. The Social Security Administration is a federal government department. It is, however, administered under state law. Many state laws do not recognize foreign adoption decrees for social security purposes only as full and final. They require that the child have a U.S. adoption decree before being eligible for benefits such as disability, death, or retirement benefits. Additionally, many colleges will not offer grants and scholarships unless the child has a U.S. adoption decree.

Readoption also changes the child’s name and permits the issuance of a state birth certificate. Many states will not issue a birth certificate for your child until the readoption process is complete.

These documents and the U.S. adoption decree can be duplicated as many times as necessary
through either your state’s vital records department or your county clerk’s office in the event the originals get lost or destroyed.

©2003-2004 Legal-Eaze International Adoption Specialists, LLC Revised 05/01/04
LAW OFFICE OF C.J. LYFORD
PMB 141
12 West Willow Grove Avenue
Philadelphia, PA 19118-3952
Telephone 215-247-3888
E-mail lyfordesq@aol.com
Fax 215-247-4722
Practicing in the areas of Immigration/Citizenship/Visa Law
and International Adoption Law