Michael Ultimately, the German government is interested in not having every Tom, Dick and Harry running around with a German citizenship, even if they don't need it, and you've got to admit that that makes a lot of sense. Double citizenships create a bureaucratic mess, and should only be tolerated in exceptional cases. That is why basketball player Schrempf lost his German citizenship when he accepted the American one. We, on the other hand, submitted an application in which we demonstrated that we would suffer significant disadvantages if we a) did not accept the American citizenship and b) lost the German one.
It is important to treat and justify these two disadvantages separately. Saying "I just want to vote in America" or "even as an emigrant I still read the Süddeutsche Zeitung online" does not count and the application will be rejected. But someone who, for example, shows professional disadvantages because certain positions in America are only given to citizens, or is still rooted in Germany and has parents, a bank account or a side job there, can justify that he actually needs two citizenships for the simplification of his life.
The German authorities acknowledge that Germans who have been living in the US for more than 20 years (10 years for retirees) are entitled to US citizenship and therefore do not need to justify this, but rather only need to explain what ties they still have to Germany and why they wish to retain their German citizenship. We mentioned our parents, relatives and friends in Germany, and even reported on our fostering of German culture in San Francisco, as we meet with friends here on a regular basis to play the Bavarian card game of Schafkopf.
To be submitted are the following documents: the "Application for Retention, Form B", a certified and a simple copy of the German passport, a certified and a simple copy of the US residence permit, evidence of the continuing ties to Germany, as well as evidence of the reasons for accepting US citizenship, all with copies. For inexplicable reasons, those living in Miami even need two copies. Whoever thinks that "certified" means stamped by one of the so-called "Notary Publics" in the USA is mistaken. The copies must actually be certified at the consulate on site, for which one needs an appointment again.
Once everything is complete, the bundle is sent by regular mail to the consulate. After a few weeks, we received an email confirmation, when the application was sent internally from the consulate in San Francisco to the authorities in Germany by diplomatic mail. From the time the application was sent until it was approved, a year and three months had passed for us. In the meantime, we received emails from the application processor in Osnabrück/Germany, and had to obtain some additional documents, have them certified, and send them in. Finally, we received confirmation by email and then by letter that a decision had been made on our application. To pick up the certificate, we then needed an appointment at the consulate, which we got two months later. The fun is not cheap either, as a fee of 255 euros is charged for each BBG certificate, and even if the application is rejected, 191 euros are due, according to paragraph 38 of the German Nationality Act called StAG. Incidentally, the approved retention is only valid for two years, if the U.S. naturalization takes longer, the BBG must be extended, again for a fee.