Does anyone know if there is any retention regulations on how long you should retain your old CRA public files? I know there are regs on the disclosures, but I couldn't locate anything in regards to the public file as a whole. Any guidance?

Review Section 224.43 - your public file must be current as of 4/1 of each year. It does not state that you retain your file for each year & create a new one, rather it should be "updated" at least annually.

Princess answers correctly, but I'd caution that you should save any removed items through the period of your exam. While I update my file annually, I also have a file for old data (pricing, etc) which I maintain for exam purposes. Also, there are items within your file that are "exam to exam" related (ie public comments) which you need to hang onto. Assessment area changes can effect your retention as well. I keep maps of any AA's in effect during the three year period, with notes as to which are "current" and which are from previous years as necessary.