Mark Pilgrim isn't even the original author, he just ported the C version to Python and contributed nothing to it for the last 10 years.

If you take 5 minutes to look at the code you'll see that v7 works in a completely different way, it mostly uses machine learning models instead of heuristics. Even if you compare the UTF8 or UTF16 detection code you'll see that they have absolutely nothing in common.

Its just API compatible and the API is basically 3 functions.

If he had published this under a different name nobody would have challenged it.