If you specifically mean "Copyright" in the USA then there are some guidelines that you could explore by looking up the Copyright Act of 1975, which explicitly lays out the process for copyrighting software.
In brief, if you want to copyright something, you must send a copy of it to the U.S. Copyright office. If it is long enough, you can send excerpts of a sufficient size to properly represent the code and/or look-feel issues. If you don't want to actually copyright it but want to protect it anyway, you can go through the motions. However, if you DON'T actually copyright it, you cannot effectively sue for breach of copyright unless you complete the registration (unless the law has been amended AGAIN, and I wouldn't put it past congress.)
The object (as a whole) must include a declaration that comes up stating that it is a copyrighted work in its entirety, protected by U.S. Copyright laws. I suggest a startup form with a wordy message box might be good for this. It can be an OK-only message box.
You should also make EVERY FORM include the copyright symbol (c inside a circle or if you don't have one of those, c inside parentheses, plus the written-out word copyright and the date on which the copyright began, plus the name of the owner - you or your employer or whatever.)
EVERY MODULE should include a comment line with the same exact declaration. EVERY REPORT should include this as a part of the report header or report footer. Some folks make it Page Header/Footer instead if they are paranoid enough.
There are also international standards for copyrighting text material including programs, but you would have to look them up. I believe the specific language used in the copyright notice you display has to change vs. the USA version, but it is just text to be displayed. Essentially a constant.