No Texas district is even in the top 5 for win rates for patent plaintiffs. You'd think if they were "in the pockets" of patent trolls, the trolls would achieve better outcomes there.
The actual reasons filing patent cases in EDTX is popular are:
• EDTX does not have a busy Federal criminal case load. Criminal cases have higher priority than civil cases. If you try to litigate a complex civil case in a district that has a heavy criminal load (e.g., anywhere that has a lot of drug trafficking), it can be nearly impossible to get any court time.
• Patent cases are complex. If you have a judge with little experience with patent cases, things will go slow. So, people like to file in districts that have a few judges with patent case experience.