Terms of Use for the Vchasno.Sign Online Service
Current version:05/20/2026
PDF version1. General Provisions
These Terms define the conditions and procedure for using the Vchasno.Sign online service and are binding on all Users. The intellectual property rights in the software product provided as the Vchasno.Sign online service belong to VCHASNO SERVICE LIMITED LIABILITY COMPANY.
By using the Service, Users agree to these Terms.
2. Definitions
The Vchasno.Sign online service (the Service) is a software product provided as an online service for applying electronic signatures to electronic data (files).
User means an individual, sole proprietor, or representative of a legal entity who uses the Service to initiate the application of a qualified/advanced electronic signature/seal to electronic data (files).
Counterparty means the User’s counterparty that is the addressee or recipient of an electronic document.
Other terms used in these Terms have the meanings established by the Law of Ukraine on Electronic Identification and Electronic Trust Services.
3. Conditions of Use and Signing Procedure
3.1. To use the Service, the User must:
3.1.1. Read, accept, and comply with these Terms while using the Service;
3.1.2. Read, accept, and comply with the Privacy Policy while using the Service;
3.1.3. Have a valid (not revoked) qualified public-key certificate or an advanced electronic signature based on a qualified electronic-signature/advanced electronic-seal certificate issued by a qualified electronic trust service provider in accordance with Ukrainian law.
3.2. The Service is free and does not require mandatory prior registration to apply electronic signatures to documents, but operates on a session basis.
Uploading and Managing Documents
The User may upload no more than 18 files in any format supported by the Service for simultaneous processing (batch signing) in one session.
The maximum size of one file is 10 MB.
All uploaded electronic data (files) is automatically converted to PDF to support the PAdES standard. The document’s original formatting may change slightly during conversion.
The User may rename any uploaded electronic file before an electronic signature is applied to it.
Signing Process
After electronic data (a file) is uploaded and the User selects “Sign” or “Sign all”, the Service prompts the User to choose a signature authorization method by applying a qualified/advanced electronic signature/seal from their device, selecting the trust service provider, and entering the private-key password.
Signing takes place directly in the browser. After the electronic-signature key has been read successfully and the password entered, the Service applies the electronic signature to the selected files.
The Service supports electronic signatures issued by any qualified provider in Ukraine.
Storing and Downloading Signed Documents
After signing, documents are downloaded automatically as a PDF (for one file) or a ZIP archive (for multiple files).
The link is a protected URL that can be copied from the browser and is retained on the successful-signing page. The Service automatically blocks users who attempt to guess document identifiers by systematically trying multiple values.
Privacy and Security Rules
The complete document is uploaded to the Service’s server. Signing takes place in the browser using a dedicated script.
The User must enter the electronic-signature password during every session. The Service does not store passwords.
The User cannot sign a document using an expired electronic signature. The Service automatically checks the certificate’s status in the register.
4. Other Provisions
4.1. The User bears full legal responsibility for all actions performed using their personal qualified/advanced electronic signature/seal.
4.2. Actions performed by the User on the website have the same legal effect as a handwritten signature on paper.
4.3. The Service is not responsible for the content of documents signed by the User.
4.4. The Service is not liable for losses resulting from the User losing control of their electronic signature or password. Transferring an electronic signature to another person violates security rules.
4.5. After applying an electronic signature, the User must download and retain the result of the operation.
4.6. These Terms may be amended by publishing a new version, which becomes effective when it is posted on the relevant page of the Service.