Question:
I hope this message finds you well.
Is it permissible for a Jew to be a shareholder or investor in a business that sells food which is not kosher, even if they are not involved in its operations or decision-making?
For example Pizza Hut or MacDonalds in the USA?
Answer:
Hello,
Your question applies not only to the selling of non-kosher food, but the fact that the company operates on Shabbos, may have chometz in it's possession during Pesach, and may earn money from lending money with interest.
There is controversy about this, however numerous poskim say that if it is an insignificant amount of stock, and the person doesn’t have any real say in the running of the business, then it is permitted.
Best wishes
Sources:
Mahari Halevi 2-124, Shulchan Halevi 1-4, Teshuvos Vhanhagos 1-429, Mishnah Halachos 5-79