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This page is out of date. This could probably fit in the FAQ. Please use the main navigation to find the latest documentation.

What's Wrong With Flash

Using or recommending Flash is equivalent to promoting proprietary software. In addition, the audio and video codecs claim to be patented, and the complete specification for making a compatible Flash player is not available. This page aims to document these problems and provide alternative suggestions.

Non-Free Software

The ActionScript code for a page's own Flash player is usually not free which means that you're still running non-free software in the end, even if you're using a free software player to interpret it. See "The JavaScript Trap" for more information.

A better solution is to use free and unencumbered audio and video codecs like Theora and Vorbis along with the HTML 5 video element and a free software browser that supports it, like GNU Icecat.


A major problem with the current Flash specification is that the audio and video codecs claim to be patented. This is a problem in countries that consider software patents to be valid because anyone who implements Flash must either pay for a patent license to use the audio and video codecs specified (namely the Sorenson Spark video codec, the most widely-used Flash codec, used by default on YouTube) or they must pass that cost onto the distributors and/or consumers. Most free software projects don't have the money to obtain patent licenses but even if they did, keeping track of the number of installed copies would be impossible due to the nature of free software distribution. Setting a requirement that the end user seek a patent license is normally incompatible with most free software licenses as well.

The Flash specification needs to allow for the use of free and unencumbered audio and video codecs like WebM, Theora, Vorbis or Dirac for this issue to go away. Eliminating software patents would also help: http://endsoftpatents.org.

See "The Danger of Software Patents" for more information: or RMS speak on the subject: High Res | Low Res

Non-Free Specifications

Adobe's Open Screen Project may have confused people into thinking that the Flash specification is totally open and free but, according to the Swfdec and Gnash project leads, it omits "huge amounts" of information needed to implement Flash. Additionally, the Flash specifications available from Adobe are distributed under a non-free license:

When people try to create their own independent implementations, Adobe steps in to stop them: In May 2009, Adobe submitted a takedown notice to SourceForge.net requesting that the rtmpdump project be removed from their site. SourceForge.net complied.

The major implication of this takedown notice is that Adobe has definitively told us that a fully-compliant free software Flash player is illegal. This is because RTMPE is part of Flash, circumventing RTMPE is illegal (in the U.S. at least), and Adobe will never give a key to a free software project since they cannot hide the key. As a result, we can never have a fully compliant free software Flash player that's legal to use and distribute, even if we ignore the codec patent problems.

How To Help

You can help by:


Main/WhyNotFlash (last edited 2013-09-04 22:02:47 by FelipeLopez)