Inactive Tutor answered • 23h
The indefinite pronoun in this sentence replaces a specific moun to refer to that noun in a non-specific way. While "her," "himself," and "I" are all specific, anyone could refer to a random person, place, or thing. For instance, you could replace "anyone" with a proper name (such as Matt), and the sentence would still be correct. (I gave the information to her, but Matt could have copied it for himself.)
However, replacing "himself" sounds awkward and changes the sentence meaning: I gave the information to her, but anyone could have copied it for Matt. See how it narrows it to one person? The sentence originally meant to say that any person could copy it for their own use. Now, it reads that anyone can copy it for Matt's use.
As for "her," that pronoun is referring to a specific person. The writer has a certain person in mind, and that's not a general, random person. "I gave the information to Matt, but anyone could have copied it for himself." The sentence no longer says that the speaker is giving the information to a "her" who has already been mentioned by name. Instead, it reads that the information was given to Matt, not to the mysterious "her."
