The new tag, which has begun appearing for some users of the platform, identifies the "original tweeter" in a thread.
Twitter hopes the feature will make it easier to distinguish accounts that pretend to be the person who started a thread, which may also help prevent certain types of abuse on the platform.
Twitter confirmed the experiment to TechCrunch, and said that it had rolled out the feature to a "small percentage" of iOS and Android users.
"Twitter's purpose is to serve the public conversation. As part of this work, we're exploring adding more context to discussions by highlighting relevant replies – like those from the original Tweeter," Twitter's director of product management Sara Haider told TechCrunch in a statement.The "original tweeter" tag appears to be the latest fruits of the company's new beta app, in which a select group of users gain get access to new features within a standalone app, where they can test and talk about them with others.
Twitter is using what it learns from the beta app to decide whether to make the tests part of full-blown product features for its wider user base.
The first beta is focusing on testing a new design for the way conversation threads work on Twitter. New interface elements currently under review include a different color scheme and visual cues to highlight important replies.