Depends on who you ask. ;) Seriously, not even the ATF will provide a consistent answer. On the TRA list, someone reported being told by their inspecting agent that all igniters require a LEUP and must be documented and stored. Another was told that igniters can't be stored with motors, but must be in a separate magazine. And another person was told that "we only regulate squibs, not ematches or igniters, so don't report them or store them in your magazine".
Welcome to the wonderful world of bureaucracy. As Bob K. is fond of saying, "It's the government, it doesn't have to make sense."
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