Some sites integrate the Genius JS code directly but they don't have to. As a user, you can freely annotate (nearly) any page on the web with the bookmarklet. I made numerous annotations on the famous Bloomberg "Code" article which you can see on the page at [1] or in summary from the page at [2].

For [1] to work, you need to either run the bookmarklet or Chrome extension. This isn't the norm though; most annotated pages can be viewed directly from the genius link, and you can even link directly to a specific annotation, for example [3].

[1]: https://www.bloomberg.com/graphics/2015-paul-ford-what-is-co...

[2]: https://genius.com/summary/www.bloomberg.com%2Fgraphics%2F20...

[3]: http://genius.it/7163911/www.theverge.com/2015/6/24/8836087/...

Genius is a non-scummy site, turned itself around ages ago.

Yes, either the NYT or WaPo uses them.

I've seen genius annotations of a Trump speech on WaPo.

Why do you classify genius as scummy?

For one, the Genius proxy server violates copyright and does not provide an opt-out.

How does a proxy server violate copyright? Maybe I don't understand what exactly Genius is doing, but how is this different from say blocking ad servers in my hosts file?

Derivative works of course being protected by fair use.

And if Genius is hosting the page that's annotated, that's one thing. If they're simply proxying it on demand and adding annotations, then I don't see how it violates copyright unless every proxy server violates copyright.

Derivative works are what are banned by copyright. They are the things that are not covered by fair use. Transformative works that really change a work aren't covered by copyright because they don't really count as a copy anymore. Fair use is this other thing https://en.wikipedia.org/wiki/Fair_use#U.S._fair_use_factors

The key difference is that proxy servers don't copy content. They reflect it. You can put any URL on the internet behind a proxy server-- that does not mean that the proxy server has already copied the entire internet. Nor does it mean that once a URL has been proxied by a proxy server does the content remain cached or copied-- since in our case at Hypothesis, and we presume at Genius, it does not.

This is a key distinction that separates proxies from caches and archives.

This does more than proxy, the genius proxy alters not just the underlying code that makes the content, it alters the way the content is intended to be consumed.

I'm on mobile, and all I'm getting are AMP links (ugh), but there are a lot of results when you google "Rap Genius controversy".

They tried dirty SEO tactics that Google ultimately punished them for, and their staff have made off-color remarks in the past. There's a lot more if you search for it.

And they promptly fired Mahbod:

http://www.recode.net/2014/5/26/11627246/rap-genius-co-found...

Things at Genius have been pretty controversy-free since 2014.