Comment by lostinpoetics

The main reason is to fund the office as it's one of the few agencies that is 100% funded by fees (versus appropriations). So much so that Congress often skims money from the fees they collect. The fact that the office is sort of set up like a traditional corp. (i.e., earning revenue, paying salaries, getting "taxed" by Congress) colors a lot of discussion on how the office operates, in my opinion. Also, the percentage of patents that are actually asserted in court is extremely small compared to the number of issued patents.