You can do many different things.
If it’s really 13 identical copies, I’d select one and copy it, then select all and delete everything.
Now you have a blank svg.
Paste in place and your single copy appears.
If you have 13 path objects each with different “chunks” it’s probably more like select all and union.
I’d have to look at your actual file contents to be sure what method I’d choose.
You might wonder why I’d do the copy/paste thing. Good question. Path booleans like Union have the potential to alter your original path in ways you don’t expect or want, shifting nodes around or sometimes altering the path by a tiny hair of distance. I find it’s best to modify paths with booleans as little as possible if accuracy is paramount. [e.g. inlays, butt joints… gears…]