Transit visa

[nundan]

my grandparents got visa for 3 months.It says its valid from april 6th to july 6th.
They will be travelling to USA on 21st of this month(april).Lets say they get the stamping in port of entry for four months.They might be staying for 4months.Their actual visa on the passport will be expiring on july 6th.Should they take a transit visa?
They will be coming via germany.

[Murali]

Transit visa at Germany is not reuired if they have connecting flight and they have no plan to go out of airport.