Once a memo or any other document leaves your hands, you have essentially published it.

The reality now is once your send a email, post a comment, and tweet a picture every detail is recorded and never deleted. Companies are bound by law to save all emails and exchanges within their company. Your credibility can be questioned if past emails are sourced and demonstrate negligence. Increasingly memos and documents are relayed to employees through electronic sources like email, so don't be surprised if your paper document comes back to haunt you in digital format. Documents can be scanned and photographed, so it is always important to make sure that you are putting your best out there. Out there is somewhere even after you press delete.