Yes, the content - that means unlike h.264 licensing there's no separate license for streaming (page 7 of http://www.mpegla.com/main/programs/avc/Documents/avcweb.pdf)

But with h.264, _codec_ licensing is for non-commercial (and internal business) use only (page 8).

There's no clear statement that HEVC licensing is for any and all purposes, and their use of the term "End user" in MPEG-LA's (non-binding) public material across patent pools is quite inconsistent, so it may mean only non-commercial users.

Given that it's MPEG-LA that we're talking about here, and their history, I assume there will be nasty surprises unless there's hard evidence that there aren't.

Yep, and that bit of JS you are distributing _is_ a decoder. I've been bitten by this before, and it resulted in buying the MPEG-LA a few ferraris a month after they noticed and we were popular while we worked to create an alternate solution.

Good times.

Then surely you have an issue, don't you, if you bundle the decoder in JS?

Hmm, that does make me wonder, actually - as far as I know, you can freely distribute source code for encoders & decoders without having to pay any royalties. Binaries / compiled versions are where the royalties come in. And technically, JS code is source code that gets compiled by the browser... so I'm not actually sure where it falls in all this.

I don't think source code is exempt from patents per se. I think the rule is more like some point in the supply chain has to have a license. It's common to distribute a chip or software library with no license with the assumption that the final product will get a license. But if the source code is the final product it needs a license. IANAL.