The capability to do something and actually doing something are totally different.
EMC Styleworks would have been banned long ago if owning something to convert one style format to another was illegal, however as it only provides the capabilities, not the styles, then there is no problem.
On the other hand, if the purchasers of Styleworks gives copy write styles they have converted to other formats, to someone else, then THEY are breaking the law. (Not the company that makes the software)

Livstyler will play Yamaha styles, but no Yamaha copy write ones are provided, (That’s up to the user to purchase)
Sounds for styles: (Mega voices, Loops etc.)
Analogy:
GM makes a car with 5 speed gearbox, 4 wheels, Air Conditioning, CD Player and glove box, Ford copy this and begin selling it with their own badge, GM can then sue Ford for infringement of copy write.
On the other hand, if Ford makes its own car with its own parts that does exactly the same as the GM car, GM can do nothing about it because nothing of theirs has been used.
The same applies to Mega voices, Loops etc., so that providing the manufacture does not include the manufacturers ones (He designs his own) then there is no infringement.
This is how the Wersi system works, in that Wersi designed their own Mega voices (Called ACC voices) and software, thus allowing Yamaha compatibility without infringement. (They DO NOT supply any Yamaha styles)
Like all reputable companies, Wersi informs the customer of the manufactures trademarks. (In the case of Wersi, this includes Akai, Steinberg (VST) and Yamaha)

Bill