Quick summary and translation from the license agreement provided at Deutsche Bahn Marketingportal (https://marketingportal.extranet.deutschebahn.com/marketingportal/Lizenzvereinbarung-ueber-die-Nutzung-der-DB-Type-Schriftenfamilie-9693166):
_You're only allowed to use the font in the context of your work at Deutsche Bahn or to fulfill orders and/or services, that are bound to contracts with Deutsche Bahn. Any other usage especially for private purposes or unintended third parties is strictly prohibited._

Please keep in mind that the "Lizenzvereinbarung über die Nutzung der DB Type Schriftenfamilie" (https://marketingportal.extranet.deutschebahn.com/marketingportal/Lizenzvereinbarung-ueber-die-Nutzung-der-DB-Type-Schriftenfamilie-9693166, german, you need a registration/login) are actually legally binding and this simple and translated excerpt is only giving you a quick hint regarding the whole license agreement; please consult that document for any further license questions and regulations.
