Honestly, I doubt if the top guys at Apple ever knew that edig existed.
Just like there are quite a few vineyards that can make decent wine, but that does not mean that they will sell much, I'm sure a lot of people could string together some components and try and sell a music player in competition with the Ipod.
But doing it successfully is a whole different matter.
And once it was patent troll time, Tim Cook and those guys let their lawyers handle it, the way a busy man swats away a fly without bothering to learn its name.
wsj