[dataflow]

Could someone ELI5 the following?

1. Weren't "ideas" not supposed to be patentable, but only actual implementations? Given that, how can an algorithm be patented?

2. Wasn't prior art supposed to invalidate a patent? If the algorithm was already used in JPEG-XL, then clearly Microsoft isn't the first to discover it, and hence should not be able to patent it, right? Or if the algorithm in JPEG-XL is considered different, then there's no infringement by definition, right? So what's the issue?

[ClumsyPilot]

This is a huge powergrab by our industry - it is the only industry in the world that gets both patent and copyright protection. Think about it, you can patent a car engine, but you cannot get copyright on it. You get copyright on a book, but you can't patent a book.

Also that's mostly US. By contrast, in Europe, software is generally not patentable.

[jononor]

The schematics, engineering drawings, 3d models, CAD files, process documentation etc for making a car engine (or anything else) are all copyright protected. So how exactly is software special?

[ClumsyPilot]

that's very different - does not stop me copying a car engine and selling my knockoff.

I can buy a car engine, modify it and sell my modification.

Supplimentary documentation, and schematics are a separate matter - but engine itself is not protected. Software itself is protected, you can do nothing..

[blurred]

One is theory, second is practice. Here is some discussion about this patent:

https://encode.su/threads/3863-RANS-Microsoft-wins-data-enco...

[Nokinside]

1. In patent law an idea is a creation that has been imagined but not yet prototyped, produced, or manufactured and they can be patented. Products with usefulness are patentable. Including algorithms used in software, and process (act or method of doing something)

2. In the US prior 2013 that was often the case. In 2013 US switched from first-to-invent to first-to-file system to be more compatible with the rest of the world.

[derf_]

That is a common misunderstanding of first-to-file. Under first-to-file, prior art is absolutely still a defense, and much easier to prove than under first-to-invent. If you publicly disclose something before someone who invented, but did not disclose, the same thing, your publication counts as prior art. It is much easier (read: cheaper) to demonstrate that "X document was published on Y website on Z date" than it is to start doing discovery to compare private lab notebooks or whatever to decide who really invented the thing first.

First-to-file is mostly about simplifying the complicated litigation edge cases where two people claim to have invented, but not disclosed, the same thing during the (US-specific) one-year grace period they have to file a patent on it.

Prior art may still not invalidate the patent, though. Usually the patent holder will argue that their patent differs from the prior art in some respect (you can often find these arguments in the patent's file wrapper at http://patentcenter.uspto.gov/). But that narrows the scope of the patent, and being your own prior art is a pretty good defense against infringement.