Chances are that you have shared music or other files on the Internet. Whenever you share files on the Internet you are likely using a peer-to-peer (PTP) service. PTP file-sharing is a service that allows connected users to share their files with each other almost instantaneously.

WinMX is a PTP file-sharing program that runs on Microsoft Windows operating systems. Frontcode Technologies created WinMX in 2001 and became one of the most used PTP file-sharing programs for music around 2005. It was later bought out by a community of developers and has been surpassed by other PTP networks like Gnutella and Bit Torrent. However, WinMX is still a very popular PTP file-sharing program in Japan.

So, is WinMX legal? In short, the software is legal, but the way in which you use it may be illegal.

Next, let’s explore the legality of WinMX.

Technically, WinMX is perfectly legal. WinMX is merely a PTP file-sharing service. PTP file-sharing services are simple in concept: they allow connected users to share files with each other. The more connected users, the more files there will likely be to share. However, how you use a PTP service, like WinMX, may be illegal. Huh, you ask?

In short, it is illegal for you to use WinMX to share copyrighted files without the owner’s permission. For example, you cannot allow other users on WinMX to download your music files if those music files are not owned by you (or an exception applies, like the music is in the publish domain or you receive consent from the owner). Also, buying the music file does not mean you "own" the file. This is often a great misconception. When you buy a music file (like on iTunes) or a CD, you merely buy the license to listen to the songs--but you have no actual authority to transfer those songs to others.

Violating copyright law is called copyright infringement and can carry with it some hefty civil and even criminal penalties, including jail time.

Next, let’s take a look at WinMX’s run-in with the Record Industry Association of America.

In late 2005, the original creator of WinMX, Frontcode Technologies, received a cease and desist letter from Recording Industry Association of America (RIAA). The RIAA demanded that WinMX use special filters to make it impossible for users to download copyrighted material from WinMX. Frontcode Technologies eventually was not able to comply with RIAA’s request.

As a result of RIAA’s demand, the official WinMX website and servers were shut down in September 2005. Currently, WinMX remains operable through third-party modifications.

Additionally, WinMX by default will only share audio and video files. However, if WinMX is properly configured it can share almost every type of file.

NOTE: WinMX is still operable outside the United States, as U.S. copyright law does not apply beyond international borders. Still, there are various international treaties that are in effect that may influence how other countries deal with U.S. copyright law.

Next, we’ll conclude this article with a few reminders.

You cannot share files that you do not own, unless given express consent by the owner to do so (and make sure to get this in writing).

If you own the work of art like a music file and want to share it with the world, you can freely do so.

Works of art like music files do not have to be registered with the Copyright Office to be protected by copyright law. A work of art, such as a music piece, is automatically copyrighted the moment it is put into some type of medium (e.g. CD, DVD, tape, or any other file that is on your computer). However, copyrighting works of art, like music, with the Copyright Office does give the owner more legal protections.

Finally, take a look at "Is Limewire Legal?" for further details on the legalities of peer-to-peer file sharing.