Maria Doyle Kennedy, who portrays Aunt Jocasta in Outlander, is auctioning off an Outlander season four script for episode 410 signed by the cast for charity. The auction is being held by Prop Store and the bidding will occur from May 20-31, 2019. To be able to bid on the script, you must register with Prop Store. The proceeds from the auction will benefit two charities that Maria has chosen, SiMBA and Joyful noise. More information about both of the charities can be found on the landing page for the auction. Because the auction has not started yet, the details of who signed the script are not available, but it is easy to pick out a few well-known signatures.
Source: Prop Store