Others Drinking from the Mevarech’s Kos
There is a machlokes haposkim whether there is a problem of pogum for other people to drink from the kos shel bracha after the mevarech drank from it. Strictly speaking, the halacha is that there is no concern of pogum to drink from the kos the mevarech already drank from. The issue of pogum is only for the mevarech, not for others to sip from the kos the mevarech made his bracha on, as that is all considered one “drinking,” and when the mevarech made the bracha, the wine was not pogum (מ''ב סי' קפ''ב סקכ''ד, שעה''צ סי' רע''א סקפ''ט ).
However, some are machmir for this. According to them, the wine in the kos should be fixed after the mevarech drinks from it and before he gives it to others to drink from (משמעות הט''ז סק''ד, שו''ע הגר''ז סי' ק''צ ס''ה ). Thus, some are machmir and pour wine from the bottle into the kos to fix the wine before giving it to others to drink.
According to this machmir approach, it would seem that just as the wine needs to be fixed between the mevarech drinking from it and the next person, it would also need to be fixed between the second person drinking from it and the third, and so on, as each person who drinks from the kos makes the wine pogum, requiring a new remedy (כוס ישועות ליקוטי הלכה פ''ג אות ל''א ובשם אדמו''ר מפשעווארסק שליט''א ). In practice, most people do not do this.
If one wants to satisfy this chumra, it would be best, after fixing the pogum wine in the kos, to pour from the kos into empty cups for others to drink from rather than having them drink from the kos used for Kiddush. However, this sacrifices the advantage of drinking from the same kos the mevarech made the bracha on (המבואר בס' שפתי חכמים פ' וירא ).
