I recently started buying small scale shares of various Israeli companies. I did not think to check first if they observe Shabbat and have a Heter Iska. Now I have come accross the list of the Keter institute of permitted and not permitted companies. It turns out that the majority of what I bought is not permitted (El Al, Tower Semicon, Elbit Systems). Do I have to sell the shares? If so, how urgently? Can I wait for a favorable price or do I have to sell even at a loss, in a hurry before the next Shabbat?

ב"ה Shalom, There are two issues here. One of "Chilul Shabbat" =desecration of Shabbat and the issue of" ribit" and Heter Iska. In order not to keep you waiting, I will at least answer you now in regard to "chilul Shabbat" , then you can get back to me again in regard to the Heter Iska. Undoubtedly, to begin with it would have been preferable to buy shares in company which honors Shabbat. However, after the fact, the Keter institute itself discusses this issue and says that there are those who see the share holder as if he made the company a "shaliach" an agent to carry out the desecration of Shabbat. However, following the opinion of Rav Moshe Feinstein zt"l, (אגרות משה אה"ע ח"א סי' ז)even according to the above opinion, that only applies in regard to a regular partner in the business who has a say how things are handled in the business. However, to an individual whose share in the company is negligible, this does not apply and the share holder is not considered to have appointed the company as "shaliach" to desecrate Shabbat. All the best