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My F1 visa expired in June 2018. My OPT is valid till Jan 30, 2019. I got my H1b approved this year, so officially from Oct 1st, 2018 I am on H1 now and I have H1b approval notice. I am travelling from the USA to India (where I will be going for H1b stamping) from 17th November to 10th Dec 2018 through Lufthansa and have 4 hr layover in Frankfurt, Germany. Would I need Airport transit visa? I am an Indian citizen.