If a parasha is placed in the wrong compartment of the tefillin (switched), are the tefillin valid?

Synopsis

All authorities agree that if the parashiyot are placed in the wrong compartments, the tefillin are invalid (pesulim). This applies equally to the shel yad (arm tefillin) and the shel rosh.

Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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