In the State of Washington they do not amend a birth certificate, they destroy it and replace it with a new original that has your legal name on it so when asked to state your birth name it's the one on your current birth certificate. I do not list previous names unless required to do so by statute and if there is no law that requires it I don't do it. I did not list previous names when I had a background check working on a research project in the state prisons here and it never caused any issues. I have, with the aid of an attorney on some issues, changed every single piece of identifying information linking me to a previous name all the way back to elementary school and every single place of employment all the way back to my very first job. However, those previous names are still available and liniked through NCIC and other databases such as the Department of licensing, IRS, Social Security Administration, FBI, Employment Security Department, ect.