21. Secure Electronic Record with Digital Signature. The portion of an electronic record that is signed with a digital signature shall be treated as a secure electronic record if the digital signature is a secure electronic signature by virtue of Section 13.

Source: Singapore Electronic Transactions Act §19.

Comments: This section acknowledges that an electronic record signed with a digital signature will be considered a secure electronic record.

22. Digital Signature as a Secure Electronic Signature. When any portion of an electronic record is signed with a digital signature, the digital signature shall be treated as a secure electronic signature with respect to such portion of the record, if:

(a) the digital signature was created during the operational period of a valid certificate and is verified by reference to the public key listed in such certificate; and

(b) the certificate is considered trustworthy, in that it is an accurate binding of a public key to a person's identity because the following requirements have been fulfilled:

(i) the certificate was issued by a certification authority operating in compliance with the rules made under this Act;

(ii) the certificate was issued by a certification authority outside India recognized for this purpose by the Controller pursuant to rules made under this Act;

(iii) the certificate was issued by a department or ministry of the Central Government, State Government or a statutory corporation of Central or State Government approved by Central Government to act as a certification authority on such conditions as the Controller may by rules impose or specify; or

(iv) the parties have expressly agreed between themselves (originator and addressee) to use digital signatures as a security procedure, and the digital signature was properly verified by reference to the originator’s public key.

Source: Singapore Electronic Transactions Act §20.

23. Unreliable Digital Signatures. Unless otherwise provided by a rule of law or contract, a person relying on a digitally signed electronic record assumes the risk that the digital signature is invalid as a signature or authentication of the signed electronic record, if reliance on the digital signature is not reasonable under the circumstances having regard to the following factors:

(a) facts which the person relying on the digitally signed electronic record knows or has notice of, including all facts listed in the certificate or incorporated in it by reference;

(b) the value or importance of the digitally signed record, if known;

(c) the course of dealing between the person relying on the digitally signed electronic record and the subscriber and any available indicia of reliability or unreliability apart from the digital signature; and

(d) usage of trade, particularly trade conducted by trustworthy systems or other electronic means.

Source: Singapore Electronic Transactions Act §22.