Under the FTC's Telemarketing Sales Rule: a purchase in the last 540 days or an inquiry in the last 90. Why bought leads are a gray area.
Under the FTC's Telemarketing Sales Rule, an established business relationship exists when the person bought, rented or leased from the seller in the last 540 days, or asked about or applied for the seller's product in the last 90 days. That's the definition in 16 CFR 310.2(q).
The rule's Do Not Call limits have an exception for people you have this relationship with. So the clock matters. A lead who asked about your service 100 days ago is past the 90-day window.
The relationship is with the seller. In a 2006 advisory opinion, FTC staff said that under a strict reading of the rule, a lender does not have this relationship with a consumer who responded to a lead generator. Staff said they would not recommend enforcement if the lead site made full and clear disclosures first. That's a staff opinion, not a rule, so don't treat it as a safe harbor.
The FCC has its own definition under the TCPA, and Texas has its own call rules. This is general information, not legal advice. Check your own setup with your counsel.
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