SignThis blog
How sealed e-signatures work, in plain language
A few articles on what makes a signed document trustworthy, how to check one yourself, and what security features should cost.
How to check whether a signed PDF has been altered
Three ways to tell whether a signed PDF was changed after signing: the signature panel in a PDF reader, a fingerprint comparison, and the signing service's own check.
How SignThis seals a signed document, and how anyone can verify it
A plain-language walk through SignThis's design: frozen documents, a hash-chained audit trail, a PAdES seal with an RFC 3161 timestamp, and verification that works without us.
The SSO tax, and why single sign-on is on our $30 plan
Most software sells single sign-on only on enterprise plans. What the "SSO tax" is, what CISA says about it, and why SignThis includes SSO from $30 a seat.