Filing a patent infringement lawsuit, a federal case claiming someone used your invention without permission, costs $405 to start. Completing the case typically costs hundreds of thousands to millions of dollars in lawyer fees. The $405 covers the $350 statutory fee plus a $55 administrative fee, before any attorney costs accrue, according to the U.S.
District Court for the District of Columbia in its current fee schedule. That filing fee is the smallest part of the budget. Attorney work for discovery, hearings, trial, and appeal drives the total.
Official resources:
- Read the official notice from Uscourts — Use this primary source to verify the official announcement.
- Read the official notice from Supremecourt — Use this primary source to verify the official announcement.
Table of Contents
- What You Pay to Open the Case
- What Do Smaller Cases Cost?
- Why Do Large Cases Reach Millions?
- Is Challenging a Patent at the PTAB Cheaper?
- Who Pays Lawyers When the Case Ends?
What You Pay to Open the Case
You pay the court fee when you submit the complaint in federal district court. It opens the case and covers basic court processing. It does not cover lawyers, experts, documents, or travel.
Think of the fee as an entry ticket. For most patent owners, especially individuals and small businesses, the decision turns on later legal bills. Consider whether you can fund months or years of litigation before you file.
What Do Smaller Cases Cost?
Costs rise in stages. Early work includes evidence exchange, motions, and claim construction, the hearing where the court defines the patent terms. Later work includes trial, post-trial motions, and appeal.
These are medians per case, so many cases cost more. Multiple patents, complex technology, and aggressive defense increase hours. Get a staged fee estimate before you commit.
- Less than $1 million at risk: the AIPLA 2023 survey, summarized by Taft Law, reports a median of $300,000 per patent through discovery and claim construction, plus another $600,000 per patent through trial and appeal.
- $1 million to $10 million at risk: the AIPLA 2025 survey reports medians of $600,000 through discovery, motions, and claim construction and $1 million through trial, post-trial, and appeal, according to IPWatchdog in its report on enforcement and defense costs.
Why Do Large Cases Reach Millions?
High-stakes cases escalate sharply because more money justifies more work. Teams review millions of pages, hire technical experts, and prepare detailed trial presentations. Each patent can add separate work.
For disputes with more than $25 million at risk, AIPLA-based reporting summarized by Drug Patent Watch places median total cost around $5.5 million per side. That figure shows why settlement talks often run alongside trial preparation. Weigh the potential award against the cost of chasing it.
Is Challenging a Patent at the PTAB Cheaper?
A cheaper administrative alternative exists at the Patent Trial and Appeal Board. This tribunal inside the patent office can review whether a patent should have issued. Companies often use it instead of, or alongside, district court.
AIPLA data summarized by Foley Hoag place median PTAB completion through appeal at $350,000, versus $3.1 million to trial for medium $10-$25 million district-court cases, according to Legal500 in its analysis of PTAB cost-effectiveness. PTAB review is narrower than a full lawsuit. It does not award damages for past harm.
Who Pays Lawyers When the Case Ends?
Each side usually pays its own lawyers, win or lose. That rule makes budgeting critical for consumers, inventors, and small firms. You cannot count on reimbursement. Under 35 U.S.C.
Sec. 285, courts may award reasonable attorney fees to the prevailing party in exceptional cases, a discretion the Supreme Court broadly affirmed in Octane Fitness in 2014. USPTO fees also apply on the PTAB path: inter partes review costs $23,750 to request plus $28,125 after institution for up to 20 claims, or $51,875 total, under the schedule effective Jan. 19, 2025, according to the USPTO in its current fee schedule.