A tipster told the site that security guards are patrolling the area wearing 'Apple Security' shirts.
The company built a similar structure outside of the Flint Center for the unveiling of the Apple Watch. It's likely that the new structure will similarly be used to demo the products unveiled at the media event.
Notably, Apple has typically used side rooms in Yerba Buena for demo areas, making this construction a bit of an abnormality.
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