From: Rabbi Moshe Sofer
To: Rabbi Yaakov Yitzchak Auerbach
The Chasam Sofer rules that the status of an extra lobe on the upper lung lobe depends on the direction its root inclines: if not toward the front, it is kosher (per the Dvar Shmuel); if clearly from the front, it is treif (per the Simlah Chadashah); if borderline, inflation determines it. He further rules, based on expert inspectors in Pressburg, that the direction of the root must be assessed while the lung is still inside the animal, since removal from the chest cavity can cause the root to shift and give a misleading reading.
Source: Shu"t Chasam Sofer YD §31