Based on German Missions in the United States
Airport Transit visa
Nationals of the following countries are required to be in possession of an airport transit visa when passing through the international transit area of airports in Germany:
Afghanistan, Bangladesh, Democratic Republic of the Congo, Eritrea, Ethiopia, Ghana, India, Iran, Iraq , Jordan*2, Lebanon, Mali, Nigeria, Pakistan, Somalia, South Sudan, Sri Lanka, Sudan, Syria, Turkey *1
Exceptions: Nationals of the above named countries Do NOT require an airport transit visa if
they hold a valid visa for the United States of America, or
they hold a used valid or expired visa issued by the USA and return from the USA and travel to a non-Schengen Member State within 24 hours after the expiration of their visa, or
Please refer this link below.
The 24hrs rule is almost impossible to satisfy in general cases, where a person has valid I-797 but the H1B is expired. Typically in those scenarios people continue working and make a visit to home country for visa renewal whenever they get a chance.
So unfortunate this rule is!
You can also read this page to know some exceptions:
Still, there are some categories of people, who may be nationals of the above-mentioned countries, but if they belong to one of the following they do not need to obtain a visa of this kind:
- holder of a US valid visa
- holder of a valid or expired non-Schengen country visa issued by the US
- holders of a valid visa for a Schengen Member State, Bulgaria, Canada, Croatia, Cyprus, Ireland, Japan, Romania or UK.