Here is the transcript of the German Consular office web site...
Airport Transit in Germany
Visa needed?
Entry clearance requirements are dependent on the citizenship and the resident status of the applicant. Due to its location at the heart of Europe, Germany is an important transit country. The vast majority of travellers do not need a visa when airtransitting through Germany. However, citizens of some countries do need an airport transit visa.
Please note that an airport transit visa only allows a short stay in the international transit area, neither leaving the airport's international transit area nor overnight stays are possible.
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The transcript clearly states that it is just for connecting flights...BTW, if your connecting flight requires a overnight stay , Airport transit visa is not enough.. you need to apply for a regular visa....
You need to have a Transit visa even if the connecting flights gates are right opposite to each other.....BTW, my friends flight through Paris was also like that.. No airport change.. No Terminal change.. Just a gate change........
This is a new requirement .. so travellers beware......