Inauguration - Credit: acnatta on Flickr (CC BY)
HBO has been posting takedowns on YouTube videos of the inaugural address. Whether or not they have the right to do this is in question.
Since HBO merely owns the copyright to their recording of the concert, they can’t control what other people were doing with their own recordings from their own cameras. This is because a work is not entitled to copyright protection unless it is fixed. The actual performance that happened that evening wasn’t fixed or copyrighted until it ended up on HBO’s tapes (or hard drives).
If the content of the concert was in the public domain or free (e.g., The Star-Spangled Banner is in the public domain since it was created prior to 1923), then any audience member who recorded it had the right to make a recording of it and distribute that recording since they owned the copyright to the video. Putting aside questions of anti-bootlegging laws (which are arguably unconstitutional and not relevant to DMCA takedown notices), it is not clear that HBO can prevent distributions of privately filmed performances of public domain works that were performed in a public venue, which, if the Against Monopoly report is correct, is what part of what they’re trying to do.
However, according to the Wikipedia page, a lot of non-public-domain non-free content was performed.
Weird.