If a publication platform integrates third party applications for features such as annotations or comments, the publisher should ensure that the terms of service for that application provide appropriate permission for preserving and migrating that content over time.
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14. Avoid being dependent on third party services for core features
15. Plan a strategy for preservation when third party dependencies exist
Some third-party annotation services have restrictive default terms of service or do not define their terms of service. Hypothesis, an annotation tool that can be added to or used with most websites, grants a CC0 license for all annotation data stored on their servers. This means you don’t need to seek special permission to preserve the annotation data.