No, its just outside Indian Peaks Wilderness and therefore doesn't require a permit. I verified this with the Boulder Ranger station on Friday May 29th. All the other trails that lead in (devils thumb, etc) are long enough to reach the Indian Peaks Wilderness, just not the Lost Lake trail.
Oorah Sean, but incorrect. I hiked there the weekend before last and during certain months you absolutely need a permit, it was clearly listed. I would go to the Boulder county website and find out exactly what those dates are, because I'm pretty sure it said June is when it starts.
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