Very simple and lightweight addon that mass invites the guild by ranks. You can define exactly what ranks you'd like invited in the top of the lua file.
Code:
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-- Add ranks here
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inviteRanks["Applicant"] = true
inviteRanks["Raider"] = true
inviteRanks["Core"] = true
inviteRanks["Officer"] = true
inviteRanks["Guild Leader"] = true
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-- End
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