Terms of Service
Version 2026-10
Last updated: November 2, 2026 · Effective: November 16, 2026
1. Agreement to Terms
These Terms of Service ("Terms") govern your access to and use of the ChainChum marketplace at chainchum.app ("Service"), operated by DataExpansed LLC ("Company", "ChainChum", "we", "us" or "our"), a Connecticut limited liability company with its principal place of business at 6 Landmark Square, 4th Floor, Stamford, CT 06901, USA. By creating an account or using the Service, you agree to be bound by these Terms and by our Privacy Policy. If you do not agree, do not use the Service.
Portions of the Service, such as listings, shop pages and certificate pages, are available without an account. By accessing any page of the Service you agree to these Terms; all disclaimers, limitations of liability and intellectual-property provisions apply equally to visitors without accounts.
You must be at least 18 years old to use ChainChum. By creating an account, you represent and warrant that you are 18 or older. The Service is not directed at children.
2. Description of Service
ChainChum is a marketplace where independent artists and family sellers sell originals, limited editions, handmade goods and digital downloads to buyers. Each work is sold by its independent seller through ChainChum; ChainChum runs the marketplace, takes payment, collects sales tax and pays the seller. Works sold through ChainChum come with a certificate of authenticity (section 8).
3. Account Registration
To use the Service, you must create an account through our authentication provider and confirm that you are 18 or older. You are responsible for maintaining the confidentiality of your account credentials and for all activity under your account. You agree to provide accurate, current and complete information, to keep one account per person, and to notify us immediately of any unauthorized access or use.
4. Selling
When you list a work you represent and warrant that:
- you made it, or you are the parent of the child who made it, and you have the right to sell it;
- it is human-made: not generated by AI, and not a copy of someone else's work;
- your photos, description, price and shipping details are accurate, and you will ship physical works within the handling time you set.
You keep the copyright in your work. You give ChainChum a non-exclusive, royalty-free licence to display, reproduce and resize your photos and listing details on the Service and in promotion of your work, and, where you choose print-on-demand, to print the work for buyers.
Fees. ChainChum charges a one-time certificate fee for each work you publish ($1 unless shown otherwise before you publish), deducted from the payout of that work's first sale and not charged if the work never sells, and 5% of the sale price of each item sold, which includes card processing. There are no other listing or subscription fees. Payouts are made through our payment processor once you complete its identity and bank setup; payouts for a new seller's first sales may be held for up to seven days.
Family art. Parents may sell their children's art under their own account. Family-art listings must never include a child's name, face, date of birth, school or any other detail that identifies them. We review family-art listings and remove anything that does.
5. Buying
Prices are in US dollars. Sales tax is added where it applies; ChainChum collects and remits it as the marketplace. All payments are processed by our third-party payment processor; card numbers never touch our servers. By placing an order you authorize us to charge your payment method for the total shown at checkout.
Refunds and returns. You may return an original, edition or handmade piece within 14 days of delivery: contact us first and we arrange it with the seller. You pay return shipping unless the piece is damaged or not as described. A piece that arrives damaged, never arrives or is not as described is refunded in full when the problem is confirmed. Refunds go back to the payment method you used. The full policy, including cancellations and what a refund does to the certificate, is on Returns, refunds and cancellations; how to ask is on Customer support.
6. Digital Downloads
A digital download is delivered when you pay: you download it from your order page through links that expire and can be renewed. The seller chooses a licence for each download:
- Personal use: for yourself, for example to print, frame or use as wallpaper. Not for resale, redistribution or commercial projects.
- Commercial use: also in your own projects, including ones you sell. You may not resell, share or redistribute the file itself, or sell it as your own artwork.
The seller keeps the copyright in every case. Digital downloads are final once paid, unless the file is broken, missing or not as described, in which case we fix it or refund you. A refunded download's links stop working.
7. Acceptable Use
You agree not to:
- use the Service for any unlawful purpose or in violation of any applicable law or regulation;
- sell AI-generated works as human-made, or sell counterfeits, copies or anything that infringes someone else's rights;
- list hate symbols, pornography, weapons, or anything that identifies a child; artistic nudity is allowed and must be tagged;
- arrange to buy or sell outside ChainChum to avoid fees, or send spam;
- attempt to gain unauthorized access to any part of the Service, other accounts, or systems connected to the Service;
- reverse engineer, decompile or disassemble any part of the Service;
- use automated scripts, bots or scraping tools to access the Service without our prior written consent, other than our published API and MCP tools within their limits;
- interfere with or disrupt the integrity or performance of the Service;
- upload malicious content, including viruses, malware or harmful code.
8. Certificates of Authenticity
A ChainChum certificate records who made a work, what it is and who owns it on ChainChum, and carries a fingerprint (content hash) of the work's details and photos. It is not an appraisal, insurance or proof of physical possession. Certificates are recorded on a public blockchain as tokens held in a wallet ChainChum maintains for the owner; you do not need a wallet to use them. You may export a token to a wallet you control. ChainChum does not operate a market for tokens, and transfers made outside ChainChum are shown as off-platform until claimed.
9. Intellectual Property
The Service, including its design, software, text, graphics, logos and certificate format, is the property of DataExpansed LLC and is protected by copyright, trademark and other intellectual-property laws.
Your content. You retain all ownership rights to the works, photos, descriptions and files you provide. You grant us only the licence in section 4 and the right to process your content to provide the Service to you.
AI suggestions. Listing suggestions produced by AI are suggestions only: nothing is published until you accept it, and you are responsible for what you publish. No AI ever edits your artwork image.
Copyright complaints. If you believe a listing infringes your copyright, send a notice to chainchum@dataexpansed.com with the link and your details. We remove infringing listings and close the accounts of repeat infringers. Sellers may send a counter-notice.
10. Data and Privacy
Your use of the Service is also governed by our Privacy Policy, which describes how we collect, use and protect your information.
No sale of your data. We do not sell your personal information, and we do not share it with third parties for advertising or cross-context behavioral profiling. The only third parties that process your data are the service providers required to operate the marketplace, each described in the Privacy Policy, and the other party to your order, who receives only what is needed to fulfil it.
AI data processing. When a seller asks for listing suggestions, the listing's photos and details are sent to our third-party AI provider; listing photos are also checked for AI-generated images by an image-screening provider. This data is not used to train AI models. Your Art Vault, order details and payment details are never sent to AI providers.
Third-party AI assistants. ChainChum offers read-only tools, based on the Model Context Protocol ("MCP"), that let AI assistants search public listings and verify certificates. They return only public information, never your account, orders or Vault. Your use of any third-party assistant is governed by that provider's own terms and privacy policy, not these Terms.
11. Suspension and Account Closure
You may close your account at any time from Me › Close my account. Closing deletes your profile, shop, listings, Vault and photos. Records we must keep by law, such as order and tax records, are retained, and certificates for works you sold remain valid for their buyers with your name replaced by former owner, account deleted.
We may suspend or close accounts that break these Terms, after telling you why where we can. You may export your data at any time from Me › Download my data, at no charge.
12. Service Availability and Modifications
We aim for 99.5% monthly availability of buying and certificate pages but do not guarantee uninterrupted access. The Service may be temporarily unavailable due to maintenance, updates or circumstances beyond our control.
We reserve the right to modify, suspend or discontinue any part of the Service at any time. If we make material changes that adversely affect your use, we will provide reasonable notice by email or on the Service.
13. Limitation of Liability
To the maximum extent permitted by applicable law, DataExpansed LLC and its officers, directors, employees and agents shall not be liable for any indirect, incidental, special, consequential or punitive damages, including loss of profits, loss of data or loss of sales, arising out of or related to your use of or inability to use the Service.
Our total aggregate liability for any claims arising from or related to the Service shall not exceed the greater of the fees you paid to us in the twelve (12) months preceding the claim, or one hundred US dollars.
Sellers, not ChainChum, are responsible for the works they sell. This does not limit the refunds described in section 5 and section 6.
14. Disclaimer of Warranties
The Service is provided "as is" and "as available" without warranties of any kind, whether express, implied or statutory. We disclaim all warranties, including implied warranties of merchantability, fitness for a particular purpose, accuracy and non-infringement.
We do not warrant that: (a) the Service will meet your specific requirements; (b) the Service will be uninterrupted, timely, secure or error-free; (c) AI-image screening will catch every AI-generated work; or (d) any errors in the Service will be corrected.
15. Indemnification
You agree to indemnify, defend and hold harmless DataExpansed LLC and its affiliates, officers, directors, employees and agents from and against any claims, liabilities, damages, losses, costs or expenses (including reasonable attorneys' fees) arising out of or related to: (a) your use of the Service; (b) your violation of these Terms; (c) your violation of any third party's rights; or (d) the works you list or sell.
16. Governing Law and Dispute Resolution
These Terms are governed by and construed in accordance with the laws of the State of Connecticut, without regard to its conflict-of-law provisions.
Any dispute arising from these Terms or the Service shall first be addressed through good-faith negotiation: contact us at chainchum@dataexpansed.com. If the dispute cannot be resolved within 30 days, either party may pursue binding arbitration in accordance with the rules of the American Arbitration Association (AAA), conducted in the English language. The arbitration shall take place in Connecticut or remotely at the mutual agreement of the parties.
You agree that any dispute resolution proceedings will be conducted on an individual basis and not in a class, consolidated or representative action.
17. Changes to These Terms
We may update these Terms from time to time. When we make material changes, we will notify you by email or a prominent notice within the Service at least 14 days before the changes take effect. Your continued use of the Service after the effective date constitutes acceptance of the updated Terms.
18. Severability
If any provision of these Terms is found to be unenforceable or invalid, that provision will be limited or eliminated to the minimum extent necessary, and the remaining provisions will remain in full force and effect.
19. Contact Us
If you have questions about these Terms, please contact us at:
ChainChum c/o DataExpansed LLC, 6 Landmark Square, 4th Floor, Stamford, CT 06901, USA