They were referring to it as a "Rolling Cipher" (searchable) and reinforcing the claim based on Widevine as a protection mechanism for the (previously hosted) Y

They were referring to it as a "Rolling Cipher" (searchable) and reinforcing the claim based on Widevine as a protection mechanism for the (previously hosted) Youtube Red content. [1] They were making the case "if youtube decided to replace the rolling cipher with widevine completely, it would seriously harden the DRM protection". "Die Einordnung der "Rolling Cipher" als wirksame technische Schutzmaßnahme ist auch unter Berücksichtigung der Regelung des § 53 Abs. 1 UrhG zur Zulässigkeit von Vervielfältigungen zum privaten Gebrauch verhältnismäßig." This translates to that they think base64 is a reasonable technical measurement to protect content. By this logic they've established that URLs themselves are a valid copyright protection mechanism (encodeURIComponent uses base64url behind the scenes), which has another scale of consequences. That is why I'd argue that the court has no idea whatsoever what base64 is, what it does, or that it is even an openly defined specification as a text interchange format. I think what confused the court is the parameter shuffling for the signature parameter in combination with base64. Even though this is not encryption they made it look like effective encryption in front of the court. [1] https://openjur.de/u/2466945.html https://openjur.de/u/2466945.html