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@@ -422,6 +422,8 @@ This category is for any code project related to the Fediverse. They need not be
 
 ### Protocol specifications
 
+* [**ActivityPub Ontology**](https://github.com/steve-bate/activitypub-ontology): Turtle definitions of ActivityStreams 2.0 and Mastodon Toot vocabularies. `MIT, Turtle`
+
 * :heavy_check_mark: [**LitePub**](https://github.com/litepub/litepub) ([Fedi account](https://pleroma.site/users/kaniini)): A set of extensions to AP, being developed by devs from Pleroma and Mastodon (status: for the most part litepub group folded back into SocialCG, see: [issue](https://github.com/litepub/litepub/issues/6))
 
 * [**NodeInfo**](https://github.com/jhass/nodeinfo): Defines a standardized way to expose metadata about an installation of a distributed social network. `CC0`