Sure, but that particular horse has left the barn. There will be cases where identification is easy(-ier) but as shown in Oracle v Google, there are only so many ways to express ideas in code.
For example, I just asked Claude 2 “Write a program in C to count from 1 to some arbitrary number specified on the command line.” Can you tell me the origin of this line from the result?
for(int i=1; i<=n; i++) {
I mean, if it’s from a copyrighted work, I certainly don’t want to use it in an open-source project!
EDIT: Guessing there’s a bug in HTML entity handling.