This recently seems to have been broken. The authenticated user with a protected account cannot retrieve lists they own using lists/ownerships. The response is a “page does not exist” error.
GET https://api.twitter.com/1.1/lists/ownerships.json?screen_name=username&count=2
"code": 34, "message": "Sorry, that page does not exist."
I get that error when the screen_name value is wrong. Make sure screen_name is set to a real username.
screen_name
The error seems to have been resolved as of Friday (2/27). Lists for the authenticated protected user are being returned as expected now.
