Graphologist IsraelImaging and preservation
A picture of a handwritten signature and a certificate-based digital signature are different features. A PDF validator can report the certificate, its trust status, the signed revision and timestamp details where present. A warning about an untrusted certificate warrants examining trust settings before drawing conclusions.
If you receive only a screenshot with a green approval mark, request the signed PDF itself through a suitable channel. The screenshot preserves the appearance of the mark but does not carry the original file’s cryptographic signature for validation.