Oh wait, now they changed it to 0% monthly fee until end of beta, where it becomes 1% monthly fee after you're locked in.
They plan to leave the monthly fee up to the market. Until that is implemented the monthly 1% fee is done away with.
ShapeShift provides all the collateralized ETH capital on the Seller side but in the future, Prism will open up the Seller side, such that Prism customers can take the long or short position on any basket of digital assets.
When this happens, this monthly fee will be set by the market: paid by Buyers to Sellers, or Sellers to Buyers, wherever the equilibrium exists at a given point in time. That was always the long-term plan, so weve done away with the arbitrary 1% placeholder in the interim.Source:
https://blog.prism.exchange/blog/prism-fee-update/