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J·BJon BishopIndependent growth marketer

Internet infrastructure · TLS certificate issuance and domain-security observability

Certificate Transparency (CT) Logs: coverage and access

Monitor a company's domains and brand for newly issued certificates, identify unexpected subdomains or certificate issuance, and trigger security or customer-notification workflows. SaaS security founders, domain-monitoring products and developer tools that need near-real-time certificate visibility.

What it covers

Geography and granularity

Geography: Use the geography stated by the source; coverage can vary by dataset and release.

Granularity: Monitor a company's domains and brand for newly issued certificates, identify unexpected subdomains or certificate issuance, and trigger security or customer-notification workflows.

Source type: TLS certificate issuance and domain-security observability

Potential use

Monitor a company's domains and brand for newly issued certificates, identify unexpected subdomains or certificate issuance, and trigger security or customer-notification workflows. SaaS security founders, domain-monitoring products and developer tools that need near-real-time certificate visibility.

Access and cost

Public source

Publicly auditable log ecosystem: the official log list identifies current usable logs, and the logs are append-only ledgers of certificates created, updated and expired.

Cost: Current price was not established in this review; check the provider's access terms.

Update cadence: Release cadence was not normalized in this review; check the source's dates, update notes, and API limits before comparing periods.

Interpret carefully

Limits that affect the decision

CT is a log ecosystem rather than one canonical database: coverage and querying depend on participating logs and their operational status, and the official page's list is explicitly current/usable rather than permanent.; The log list spans logs operated by different organizations and jurisdictions; visibility depends on certificates submitted to participating CT logs, not on a geographic census of every TLS deployment.; Logs preserve issuance-related history as append-only records, including certificates created, updated and expired; the official page specifically lists current usable logs, so operators and availability can change.

Release cadence was not normalized in this review; check the source's dates, update notes, and API limits before comparing periods.

This record summarizes source documentation; Jon Bishop did not conduct an independent audit of the underlying dataset.

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