His US passport application says that he emigrated to the US from Germany in August 1876. It also names his wife as Sophie, born in Germany. It gives their address as Lexington Avenue, New York City.

His passport application declares an intention to sail to Europe in April 1922 to visit relatives; in October 1922 a David Staub aged 64 years and Sophie Staub aged 59 years sailed from Hamburg to New York City. I assume this is David and his wife returning from that trip.