All Breaches
April 12, 2016 Verified Marketing

KnownCircle 2016 Data Breach

The KnownCircle 2016 data breach covers data obtained from the former marketing-automation platform for real-estate, insurance, and professional-service providers. A verified external record reports 1,957,600 unique email addresses.

2 Million
Email Identifiers
7
Data Types
Critical
Severity
Oct 10, 2026
Last updated

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Exposed Data Types

7
  • Email addresses
  • Email messages
  • Genders
  • Names
  • Passwords
  • Phone numbers
  • Physical addresses

About This Breach

That figure is not treated as a count of accounts or unique people. Production has no KnownCircle import job or local person-level data.

What does the source say about the event?

The external breach record uses April 12, 2016 and describes an outside party obtaining a large volume of data from the now-defunct service in approximately April 2016. It says the JSON-formatted dataset contained gigabytes of marketing data related to the real-estate and insurance sectors, including logs of emails sent and gift-card tracking. The original access method, exact access day, publication time, and company response are not disclosed.

The structured classes are email addresses, email messages, genders, names, passwords, phone numbers, and physical addresses. The list does not mean every field occurred together for every person. Payment cards, bank accounts, government identification numbers, and Social Security numbers are not classes in the external record.

What is the boundary of the password class?

The external source ties the password field to bcrypt hashes for a small number of KnownCircle staff, not to the full customer population. The entry is therefore not interpreted as a general customer-password leak or a plaintext-password event. The bcrypt statement also does not by itself prove that passwords could not be recovered; it identifies only the reported storage representation.

How were the domain and local scope checked?

A 2017 web archive verifies that KnownCircle offered customer-relationship, email, gift-card, and digital-marketing tools to insurance agents, realtors, and other service providers; the archive is not an incident notice. knowncircle.com currently redirects to another Known-branded page and no longer presents the former service. The company link therefore opens the incident-period archive.

Production has no import job associated with the KnownCircle identity, and the email, username, password, identity, phone, IP, personal-field, sensitive-data, and general breach-data collections all contain zero local associations. The external email measure is not presented as locally searchable records. A former KnownCircle staff password should be changed wherever it was reused. Other people should independently verify real-estate or insurance messages that use a name, email, phone number, or address through a known institutional channel.

Verification and editorial method

LeakData compares the incident name, date, affected-record count, and exposed data types with accessible sources. Unverified fields are not presented as facts, and records are updated when new evidence becomes available.

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