There are some blacklisted licenses known to Mach3.
Extracted from .062 executable:
Schopler Juberian Allison Scanners bassam PAPA FABIO Ivan Todosijevic Sompob Advanced Control Tech (ACT) MaoA~A ¯Ðtonar rebecca crans Vortech CNC Jeff Sandstrom Maksim Amvtonar
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These licenses appear to work, but as far as I heard, can produce some quirks:) What the quirks are, I don't know exactly, but as far as I've heard, "tool breakage" in canned drill cycles ... (movement to next hole to be drilled without lifting tool out of already drilled hole.