# Lesson 3 complete: transfer floor, orphan-list still shaky

Learner finished lesson 3. Treat as known: transfer moves ownership (`byteLength === 0`); typed arrays are not transferable (put `.buffer` in the list); BroadcastChannel/IDB/History have no transfer list; a detached buffer cannot be cloned again. Missed C: transferring a buffer that is **not in the value graph** still detaches the source, and the clone never receives it — the list is a marker, not a second payload. Next ZPD: deal-breakers (proxies, cost, implicit APIs, wrong-tool) with a second pass at the orphan-list rule.