Question: May Anim Z’mirot be said without a minyan?
Response: Some people think the answer to this question is no because they think Anim Z’mirot is a davar she’bikedushah by dint of the fact that people stand and open the aron during its recital, which is done in a responsive fashion.
However, people stand and answer responsively during the recital of Lecha Dodi and yet it is not a davar she’bikedushah since it can be said without a minyan present. Furthermore, the tefillah of Avinu Malkeinu is recited responsively, with all standing, while the aron is open, and yet, the Mateh Efraim (584:14) rules that it can be said even without a minyan. This ruling is based on the p’sak of the Taz and Aruch HaShulchan (Yoreh Deah 242) that the public only stands during Avinu Malkeinu because it is custom, not law.
The commentary of the K’tzeh Hamateh (HaRav Chaim Tzvi Ehrenreich) cites numerous sages that agree with this ruling. Yet, he also cites a number of gedolim who disagree and maintain that Avinu Malkeinu can only be said with a minyan. Indeed, the Gemara (Ta’anit 25b) states that Rav Akiva went down to the teivah to say Avinu Malkeinu. This clearly implies that it was recited as part of a minyan.
Interestingly, the very custom of standing for Avinu Malkeinu or Anim Z’mirot may be at the root of the machloket. Perhaps standing for these tefillot (due to the aron being open) automatically transforms them into divrei she’bikedushah. If they do, then these tefillot may only be said with a minyan. If they don’t, they need not be.