Q. E-commerce & electronic transactions on Yom Tov (when unlike Shabbos the markets & banks are open):
Although there’s already different contemporary Poskim ruled on the above, I’d very much like to know your and Rav Miller’s ruling specifically with the following:
E-Commerce: Must one disable selling a web shopping cart if he know the funds will arrive in his bank account on Y”T? Please elaborate.
Online-Brokerage: Must one cancel before Y”T any remaining open stock/options electronic orders in case they may get fulfilled (automatically IF it meets the target price) on Y”T?
If yes, to what extent does this apply? Ie: It may even be forbidden to own shares where a bank would automatically pays & re-invest the dividend on Y”T.
Yeasher Koichachem!

A. Horav Shlomo Miller’s Shlit’a opinion is that operations, sales and purchases, that are done automatically by a preset program, where no human intervention is needed, are not different than any Shabbos timer that does melochos on Shabbos by itself, after being programmed before Shabbos. However, when the instructions to do a melocho on Shabbos involve, directing people to do a melocho for you specifically on Shabbos, it is prohibited. This includes also program instructions, that if a designated operation has not taken place until the end of the projected schedule, because necessary conditions were not met (such as reaching a designated high price), then it should take effect anyway at the program’s end, when the termination takes place even on Shabbos. This is tantamount to instructing that the operation should be done on Shabbos. The same applies when one enters assets to be auctioned and give instructions, that if the sought price is not met, then they should be sold anyway, and the operation will be on Shabbos and people not, programs will be biding and buying.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a