Q. Is it permitted to use “Post-It Notes” (aka “yellow stickies”) on Shabbos? In particular I use these as book marks, since I can stick them in the margin and they mark the exact place where I left off reading. I find this especially useful when going back and forth between passages in different seforim. Can I remove and restick them on Shabbos? (I am always careful not to stick them over actual writing to avoid any possibility that they will remove ink.)

A. Poskim disagree if one transgresses the melacha of Tofer or sewing when it is intended to remain only temporarily. Some are stringent (Mishna Berura 340: 27, Shulchan Aruch Harav 340:13, Minchas Yitzchok 8:31, Chazzon Ish- hashmotos 156:2:page 257, Tehilla L’Dovid 340:6, Shevet Ha’Levi 5:50, Toras Hamelochos quoting the opinion of Horav Elyashiv Shlita) and some are lenient (Darkey Moshe 340: 2, Aruch Hashulchan 317:23, Tzitz Eliezer 13:43:3, Megilas Sefer 23:3, see Toras Hamelochos page 138, Nishmas Shabbos 4:184. 39 m’leches: Tofer).

Many Poskim permit temporary gluing or taping such as diapers that are intended to be opened for inspection and closed again (Sh’miras Shabbos Kehichoso 15: 81, 39 Melochos: Tofer n. 10 quoting Horav Moshe Feinstein zt”l et. al.) Poskim permit Velcro as it is considered “derech tashmisho” or the way it is normally used.

Although Post- It- Notes are permitted by many (Nishmas Shabbos 7:206 et. al.) Horav Yisroel Belsky Shlita has been quoted as being stringent (Halachically Speaking 3: 14 n. 54).

Horav Shlomo Miller’s Shlit’a opinion is that Post- It- Notes are permitted when used temporarily, not stuck tightly and therefore easily removed.

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