Stockwyn

Terms of service

Version 2026-09-19, in force since 19 September 2026

These terms apply to the use of the Stockwyn app. Please read section 6 carefully: it explains what Stockwyn can and cannot prevent.

1. Who you contract with

Your contract is with the operator of Stockwyn named in the legal notice. You can reach us at hello@stockwyn.com.

2. Business customers only

The Stockwyn app is offered only to businesses and self-employed sellers who use it for their commercial activity, not to consumers. By installing the app you confirm that you use it for business purposes. Terms of your own that conflict with these terms do not apply, even if we do not object to them.

3. What the service does

Stockwyn connects a Shopify store with marketplace seller accounts. Today this is eBay; a connection to Etsy is in development, and section 12 describes how it works. For eBay, Stockwyn links existing eBay listings to Shopify products and sets the available quantity of the linked listings from your Shopify stock. If you switch price sync on, it also sets the price of linked fixed-price listings to your Shopify price plus the markup you choose. If you switch order import on, it also creates your eBay orders in Shopify and reports their shipments, with tracking numbers, back to eBay.

  • Stockwyn does not end, create or rewrite eBay listings. On linked listings it changes only the available quantity and, if you switched price sync on, the price.
  • Stockwyn changes quantities on eBay only after you have switched stock sync on. Before that, the check in the app shows the real quantities on eBay and what Stockwyn would change, without changing anything.
  • Stockwyn changes quantities only while eBay's out-of-stock control is on in your eBay account, so a listing that reaches 0 stays online instead of ending.
  • Stockwyn changes prices only after you have switched price sync on, which is possible only after the check in the app has shown you the current eBay prices and what Stockwyn would set. It changes prices only on fixed-price listings in your shop's currency, never sets a price of 0, and does not lower a price to less than half of the current eBay price.
  • A change counts as confirmed only once Stockwyn has read it back from eBay.
  • When you disconnect eBay, or connect a different eBay account, your links are deleted and stock sync and order import are switched off. Your eBay listings stay as they are.

Stockwyn is a new product. Features can be added, changed or removed over time; we announce changes that matter to you by email or in the app. The current scope is described in the app.

4. Your responsibilities

  • Check your stock rules (locations, buffer, maximum) and the result of the check with eBay before you switch stock sync on, and again whenever your setup changes.
  • If you use price sync, keep your Shopify prices correct: apart from the limits in section 3, the eBay price follows your Shopify price and markup.
  • Keep SKUs in Shopify and on eBay accurate. Products Stockwyn cannot match with certainty are not synced until you link them.
  • Keep eBay's out-of-stock control switched on. While it is off, Stockwyn does not change quantities.
  • Before you switch order import on, switch off order import in any other app you use for eBay. Otherwise an eBay order can be created twice in Shopify.
  • You remain the seller. You are responsible for your listings, prices, fulfilment, customer service and for complying with the rules of eBay and Shopify.
  • Do not use Stockwyn in a way that breaks the law or the rules of eBay or Shopify, or that puts an unreasonable load on the service.

5. Plans, trial and billing

  • The plans and prices are shown in the app and on this website. Billing runs through Shopify's billing system and follows Shopify's terms for app charges.
  • Each store can use the 14-day free trial once. If you cancel during the trial, you are not charged.
  • Plan limits (such as eBay orders per month) do not stop syncing. If a store regularly exceeds its limit, we will ask you by email to move to a suitable plan.
  • The first 50 stores keep their launch price for as long as their subscription continues without a break.
  • You can change or cancel your plan in the app at any time. Uninstalling the app also ends the subscription. After that, Stockwyn charges nothing further.

6. What Stockwyn cannot guarantee

Stockwyn is built to reduce overselling, but it cannot rule it out. Stockwyn depends on Shopify and eBay: their notifications can arrive late or not at all, their systems can be unavailable, and changes can be rejected or delayed. When stock is unclear, Stockwyn holds back and warns you rather than guessing, which can also mean a listing is not updated.

We therefore do not guarantee that quantities or prices on eBay and Shopify match at every moment, that every order is imported, or that the service is available without interruption. Handling oversold orders with your buyers remains your responsibility.

7. Liability

We are liable without limitation for damage caused intentionally or by gross negligence, for injury to life, body or health, under the German Product Liability Act, and where we have given a guarantee.

For slight negligence, we are liable only if we breach an obligation that is essential to the contract and on which you may regularly rely (a cardinal obligation). In that case, our liability is limited to the damage that is typical and foreseeable for this kind of contract.

Otherwise, our liability is excluded. These limits also apply to our employees, representatives and agents.

8. Data protection

How we process data is described in the privacy policy. Where we process personal data of your customers on your behalf, we do so as a processor under the data processing agreement, which forms part of these terms.

9. Ending the contract

You can end the contract at any time by uninstalling the app. We can end it by giving at least 30 days' notice by email. Both sides can end it immediately for good cause, for example serious or repeated breaches of these terms. When a store uninstalls the app, its data is deleted as described in the privacy policy.

10. Changes to these terms

We may change these terms, for example when features, prices or legal requirements change. We will tell you about changes by email or in the app at least 30 days before they take effect. If you do not agree, you can end the contract before that date. Changes to the price of your current plan apply only if Shopify's billing system asks you to approve them.

11. Support and language

Support is provided in writing by email at hello@stockwyn.com. These terms are written in English.

12. Etsy connection

The connection to Etsy is in development and not offered yet. This section applies once it is offered. Each seller connects their own Etsy shop with OAuth; the Etsy API key stays with Stockwyn and is never shared.

  • If you connect an Etsy shop, Stockwyn will change only the quantity of the Etsy listings you have linked. It will never create, end, delete or renew an Etsy listing, and it will not change titles, descriptions, photos or variations.
  • Before Stockwyn writes to Etsy for the first time, you will see a preview that you confirm. A change will count as confirmed only once Stockwyn has read it back from Etsy.
  • You remain responsible for complying with Etsy's terms of use and seller policies. Sections 4, 6 and 7 apply to the Etsy connection in the same way as to eBay.
  • You can disconnect your Etsy shop in the app at any time. Your Etsy data is then deleted as described in the privacy policy.

DISCLAIMER: THIS APPLICATION IS SOLELY PROVIDED BY MARCO LANGE, TRADING AS STOCKWYN (THE “APPLICATION DEVELOPER”). YOU ACKNOWLEDGE THAT ETSY, INC. AND ITS AFFILIATES ARE NOT THE APPLICATION DEVELOPER, DO NOT PROVIDE THE APPLICATION SERVICE, AND MAKE NO WARRANTIES OF ANY KIND WITH RESPECT TO THE APPLICATION OR DATA ACCESSED THROUGH IT.

The term 'Etsy' is a trademark of Etsy, Inc. This Application uses Etsy's API, but is not endorsed or certified by Etsy.

The term 'Etsy' is a trademark of Etsy, Inc. This application uses the Etsy API but is not endorsed or certified by Etsy, Inc.

13. Final provisions

German law applies, excluding the UN Convention on Contracts for the International Sale of Goods (CISG). If a provision of these terms is invalid, the remaining provisions stay in effect.