Terms of Service
Effective date: August 8, 2026
1. Agreement to These Terms
By using this Service, you are deemed to have agreed to these Terms of Service and the Privacy Policy. If you do not agree, please do not use this Service.
2. Nature of the Service and Mail Relay
This Service issues each user a USOM email address and, using that address as a point of contact, receives, stores, displays, sends, and relays email. Where configured by the user, mail arriving at USOM is forwarded to an external mail service. When a user replies from a forwarding destination such as Gmail, that reply is delivered to USOM and may be relayed to the original sender based on delivery information USOM retains.
Relayed mail is treated as having been sent through USOM. USOM does not guarantee identity verification of senders or recipients, the authenticity of any email, the safety of delivery destinations, that a conversation will be established, or complete anonymity. This Service, including any features provided free of charge, is provided "as is," and USOM does not warrant fitness for a particular purpose, continuity, completeness, accuracy, availability, or security.
3. User Responsibility
Users shall use this Service at their own responsibility and shall not rely on this Service alone for receiving, storing, forwarding, relaying, or backing up important email. Users must hold the authority to manage and use the relay destination mailbox and must secure any authority and consent necessary to process the relayed mail.
Users must not use this Service for purposes that infringe third-party rights, fraud, phishing, spam, malware distribution, impersonation, unauthorized forwarding, unlawful relay of confidential information, or any other unlawful or improper purpose.
4. Rules for Use of Mail and Content
Users warrant that they hold lawful rights of use for any email or other data sent or received through this Service. The following acts are prohibited:
- Sending spam, indiscriminate advertising, chain mail, or other bulk mailings
- Phishing, fraud, impersonation, intimidation, harassment, or stalking
- Sending or receiving malware, viruses, or malicious scripts
- Use that infringes third parties' personal information, copyrighted works, confidential information, or other rights
- Circumventing restrictions on this Service, scraping, excessive automation, or improper use of resources
- Any other act that causes harm to the operator or third parties, or that violates law or public order and morals
The operator may review stored email and other data to the minimum extent necessary for operating the Service, preventing improper use, responding to incidents, or complying with law.
5. Relay Settings and Delivery
If there is an error in the relay destination, forwarding destination, reply-to address, or other delivery settings registered by a user, mail may be misdelivered. Users shall verify their settings and delete relay settings that are no longer needed.
The receipt, forwarding, and reply relay of email, and the linking of delivery information, may be delayed, rejected, duplicated, misdelivered, or fail to complete due to external mail services, networks, spam determinations, or other factors. Users shall not rely solely on USOM's display to determine whether email routed through USOM reached the other party.
6. Suspension and Deletion
The operator may suspend, modify, or terminate all or part of this Service without prior notice for reasons including maintenance, incidents, security measures, legal compliance, or the discontinuation of external services. Where improper use is found or suspected, the operator may suspend or delete the relevant account, email address, email, or other data.
7. Disclosure of Information
The operator may, in accordance with applicable law, disclose or provide user information, logs, email, or other data upon a request from police, courts, administrative agencies, telecommunications carriers, or other bodies with legitimate authority, or where necessary to respond to unlawful acts, rights infringements, attacks on the Service, or other issues.
8. Disclaimer
The operator is not liable for damages arising from non-delivery, delay, duplication, misdelivery, loss, or corruption of email; deletion following expiration of the retention period; suspension of an account or address; interruption of the Service; failures of third-party services; a user's device or communication environment; unauthorized access; or other causes not attributable to the operator.
Even where the operator is guilty of slight negligence, the operator's liability shall, to the extent permitted by law, be limited to ordinary and direct damages actually incurred by the user, and the operator shall not be liable for lost profits, loss of data or opportunity, or indirect or special damages. This section does not exempt the operator from liability for its own willful misconduct or gross negligence, for damage to life or body, or for any other liability that cannot be exempted or limited by law.
9. External Services
This Service uses third-party services for authentication, hosting, databases, email delivery, and other purposes. The operator makes no warranty regarding changes to the specifications, suspension, failure, or changes in terms of any third-party service.
10. Changes to These Terms
The operator may amend these Terms as necessary. Amended Terms take effect from the time they are posted on this Service.
11. Governing Law and Jurisdiction
These Terms are governed by the laws of Japan.
For any dispute arising between a user and the operator in connection with the use of this Service or these Terms, the Tokyo District Court, as designated by the operator, shall have exclusive agreed jurisdiction as the court of first instance.
The Japanese-language version of these Terms is the authoritative text, and versions translated into languages other than Japanese are provided for reference only. If there is any discrepancy between the Japanese version and a translated version, the Japanese version shall prevail. The provisions of this section regarding governing law and jurisdiction apply equally to every language version made available.
