First of all, who is this Kenyon person? Apparently, she's also a writer of fantasy novels and her best-selling Dark-Hunter books, that dates back to 1998, is where Cassie copied her Shadowhunter ideas from, which Cassie first published in 2007.

image from http://shadowhunters.com/

Okay... I'm shocked about this news, and to claim that Cassie copied ideas to create the Shadowhunter world is ludicrous to me. Well, Obviously I'm a big fan and on Cassie's side.

The lawsuit that was filed states these similarities between the series:

-They are both given a manual on how to conduct their mission and on how to conduct themselves when dealing with other entities and species in their fictional world.

-Both series employ a line of warriors who protect the normal world from demons
-In both series, a young person becomes part of the Dark-Hunters’ (or Shadowhunters’) world after being saved by a gorgeous blonde Dark-Hunter (or Shadowhunter)
-They each must kill their demonic father

-Both Dark-Hunters and Shadowhunters have enchanted swords that are divinely forged, imbued with otherworldly spirits, have unique names, and glow like heavenly fire. (X)

For me, the statements above are too broad and too common an element of a story to be substantial as point of basing her claims of copyright infringement. There are other stories with these elements, she might as well sue them too.

Courtney Milan, a historical romance writer, has this to say:

“Sherrilyn Kenyon didn’t invent the idea of band of humans fighting supernatural”, and that “she’s claiming ownership over the idea that most humans are blind to a supernatural world and are given a name. She didn’t invent that.”

“Ninety-five per cent of what she is claiming are character tropes and journeys and items from our shared literary background,” wrote Milan on Twitter. “Literally both stories draw from our collective mythological history. THAT’S WHY THERE ARE SIMILARITIES … fundamental to the idea of copyright protection is that you can’t copyright ideas, only the expression of them … If you could copyright ideas, nobody would be able to write anything. Ever.”

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