It would be interesting if anyone knew a little bit more about the size of the book, type of strategy he ran (any industry preference for example), etc. inside of Citadel, but as the article says, he has been doing extremely well.
First big name spinning out on his own in 2019 as far as I've seen and looks like Ken Griffin will be putting some money into the firm as well. Will be interesting to see the size of his new fund and how many (if any) people he'll be able to take with him. I'll try to update this with additional information as I see it.
UPDATE - 1/18/2019
Citadel axed L/S portfolio manager Adam Wolfman and his team from Surveyor, which is also losing Jack Woodruff
Link [BI Prime]
Haven't read the full article (don't have BI Prime), but assuming this is related to performance given Citadel is letting him go. Will continue to update as I see anything.
UPDATE - 3/7/2019
Citadel to close Aptigon stock unit, Felder leaves
Citadel plans to shut down its Aptigon Capital equities unit two years after launch it. Additionally, the firm is parting ways with the unit's chief, Eric Felder.