In the One-Piece manga and anime they showed that when a devil-fruit user dies, his ability leaves his body, and materialises in a nearby fruit (like how Smiley's axolotl or and Ace's flare-flare ability became a new fruit).
But what happens if you dye with a SMILE in your body? Does that become a proper devil fruit, a new SMILE fruit or it never becomes a new fruit?
SMILE fruits are man-made Devil-fruits. That being said they have not been completely talked about in depth. We saw previews of side-effects from users. The episodes on Punk-Hazard with Caeser Clown talk a little about SMILEs but nothing about when a person dies. We see that a side-effect may be the fact that the person has a hard time transforming back to a human and may also get black horns (Island of Zou, Zou Arc).
Because the fruits are man-made and have obvious flaws, I would guess that they would not be recreated if someone died, otherwise there would be no need for multiple factories. That is an opinion though.
