curl -i -X GET "https://api.box.com/2.0/users/12345/memberships" \
     -H "authorization: Bearer <ACCESS_TOKEN>"

{
  "total_count": 5000,
  "limit": 1000,
  "offset": 2000,
  "order": [
    {
      "by": "type",
      "direction": "ASC"
    }
  ],
  "entries": [
    {
      "id": "11446498",
      "type": "group_membership",
      "user": {
        "id": "11446498",
        "type": "user",
        "name": "Aaron Levie",
        "login": "ceo@example.com"
      },
      "group": {
        "id": "11446498",
        "type": "group",
        "name": "Support",
        "group_type": "managed_group"
      },
      "role": "member",
      "created_at": "2012-12-12T10:53:43-08:00",
      "modified_at": "2012-12-12T10:53:43-08:00"
    }
  ]
}