Whether a yeseres leaning toward the back of the lung renders an animal treif

Description

The Chasam Sofer distinguishes between blitah (protrusion at the root) and ikum (bending at the tip): only a true protrusion at the root measuring at least a tarpa d'asa renders the animal treif, while mere curving of the tip toward the back after inflation does not. He sides with the majority of poskim against the Yam Shel Shlomo's stricter rib-rubbing rationale, affirming the ruling of the Zivchei Shelamim and concluding that one who is lenient for a Jewish-owned animal has solid grounds.