Four to five pulsating bright lights that would fade in and out and would move around each other.

Flying between Austin, TX and Montreal at 41,000 feet over the Great Lakes, we saw four to five bright lights for a period of at least thirty minutes. They were in front of us and well above us in altitude, and although we traveled well over two hundred miles during that time they always seemed to remain the same distance out ahead of us (hard to tell how far, but they were not close….maybe a hundred or more miles ahead of us). These lights moved up and down and from side to side and would disappear and reappear, and their level of brightness would change constantly. White in color. Another airliner reported seeing the same thing. Air traffic control said they had no traffic above us and recommended we report here.