Русско-англо-русский юридический словарь

On legal documents, you often see, "signed XYZ for and on behalf of ." This is because for and on behalf of mean different things.

'Can I sign for my friend?' = Can I sign in place of/as a substitute for my friend? 'Can I sign on behalf of my friend?' = Can I sign as the agent of my friend? (i.e., "and the implications will be as if he signed it.) (WordReference.com)