Hi. Is it ok to leave the sticker that says the Mezuzah was computer checked on the back of the Klaf? Or is it like extra words in the Mezuzah and it would be Pasul? Please provide sources. Thank you
The sticker on the back should l’chatchila be taken off. It is only there so the customer should know that it was checked, and there shouldn’t be anything extra added to the mezuza. I haven’t seen anyone specific that discusses a sticker, however this is what the poskim say.