If you've already gone to the length of defining your DTO with 20+ typed fields including comments/annotations etc., why should you need to duplicate it between CREATE and PUT types? PATCH is probably the trickiest one to do cleanly - while I've used the model of "re-use the CREATE type, but all fields are now optional" in the past, I wouldn't actually recommend it, and probably promote proper JSONPatch format instead, the only real disadvantage being that it's a harder to manually construct the request body, which isn't something you should be too concerned about end-users having to spend time doing.