What can I do if a buyer shares my information with someone I never approved?

If the buyer signed a confidentiality agreement, sharing your information with someone outside its permitted scope — beyond the buyer's own defined representatives, or without your consent where the agreement requires it — is generally a breach by the buyer, even if the unapproved recipient itself has no direct agreement with you. Your remedy runs against the buyer as the party you contracted with, not against the third party they shared it with, unless that third party also had reason to know the information was confidential and misused it.

Practically, start by demanding the buyer confirm what was shared, with whom, and require that the recipient return or destroy it and confirm they haven't used or further disclosed it. Review whether continuing the relationship with that buyer still makes sense, and consider whether the breach affects other protections you were relying on, like exclusivity. Whether formal legal action makes sense depends on how serious the disclosure was and what harm it's caused or risks causing. A Treadstone business lawyer can assess the breach against your agreement and help you decide on next steps.