The answer:

The device local name string is specified to be encoded in UTF-8. However, the Microsoft Wireless Notebook Presenter Mouse 8000 reports its name as Microsoft⟪AE⟫ Wireless Notebook Presenter Mouse 8000, encoding the registered trademark symbol ® not as UTF-8 as required by the specification but in code page 1252. What’s even worse is that a bare ⟪AE⟫ is not a legal UTF-8 sequence, so the string wouldn’t even show up as corrupted; it would get rejected as invalid.

Thanks, Legal Department, for sticking a ® in the descriptor and messing up the whole thing.

There is a special table inside the Bluetooth drivers of “Devices that report their names wrong (and the correct name to use)”. If the Bluetooth stack sees one of these devices, and it presents the wrong name, then the correct name is substituted.

That table currently has only one entry.