force10 vs cisco and how isnt cisco shutting them down?

Hi Team,

I played with an older force10 switch and the config is pertty much the same as cisco... you can cut and paste a config and most of it will be like for like so my question is; didnt other vendors get sued in the past does force10 have some deal with cisco and why isnt cisco going after them? i did a quick search and i couldnt find anything about this online...