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Reference: http://www.atlassian.com/licensing/marketplace/termsofuse The “Standard EULA” is reproduced here for convenience. In this case, the “Publisher” is Quabu Solutions SL.
Standard EULA
(i) The Publisher is the licensor of the Marketplace Product and Atlassian is not a party to the Publisher EULA or this Standard EULA, as applicable.
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(vi) The Marketplace Product is protected by copyright and other intellectual property laws and treaties. Unless otherwise expressly stated in the Publisher EULA, Publisher or its licensors own all title, copyright and other intellectual property rights in the Marketplace Product, and the Marketplace Product is licensed to you directly by the Publisher, not sold.