Please note that the following answer only applies to clients residing in Germany or Austria.
No, you will not be required to file any documents related to the account transfer with the German tax office.
In case you are an Austrian client, a securities account transfer may, under certain circumstances, be treated as a deemed sale under Austrian tax law if it is not reported properly or in due time. This could result in a 27.5% capital gains tax on unrealised profits. Please report the securities account transfer yourself or through a tax advisor, if applicable. Scalable Capital can arrange for the appropriate reports to be generated and made available in your mailbox. Scalable Capital does not provide legal and/or tax advice. Please check the Austrian Website for more details.