You may file alone only if everyone is a US-domiciled individual
A US-domiciled individual can still file without a practitioner, but a company or anyone domiciled abroad cannot.
Lesson 8 of 8 · 4 min
Who may act alone
Filing without a representative is called filing pro se (Pro Se Assistance Program). A practitioner is a person registered to represent others before the US Patent and Trademark Office (USPTO). Whether you may go without one comes down to who the applicant is.
An individual applicant may prosecute their own case, which means handling the application with the Office. A juristic entity, such as a company, must be represented (37 C.F.R. § 1.31). So a founder who has assigned an invention to a company should not assume they can sign for that company.
Domicile also matters. Your domicile is your permanent home, the place you live and intend to stay. Applicants and patent owners domiciled outside the US must be represented, and there is no exception for a mix of US and foreign applicants (91 FR 13510).
Three questions to ask
Work through these before you decide to file on your own, using the two rules above.
- Is every applicant a person, not a company?
- Is every applicant domiciled in the US?
- Are you ready to take on the work and the risk yourself?
If the answer to either of the first two is no, you need a practitioner. The third is a matter of judgment.
What the USPTO says
Being allowed to file alone is different from being advised to. The USPTO "always recommends" a registered practitioner, and its staff cannot give legal advice (Pro Se Assistance Program). The Office also cannot help you choose a practitioner (37 C.F.R. § 1.31).
In our judgment, the earlier lessons in this course show why that advice deserves weight. Choices about sales, disclosure and claims can be hard to undo, and you would be making them without anyone checking your work.
If cost is the barrier
Free help exists for some inventors. The USPTO's Patent Pro Bono Program offers free help to qualifying inventors, and it has income and knowledge requirements, described under Current (USPTO). The Pro Se Assistance Program is a further place to start (Pro Se Assistance Program).
Timeless wisdom
An individual may act alone, but an organization must act through a qualified representative. An applicant may prosecute their own case, a juristic entity must be represented, and the Office cannot help choose a practitioner (37 C.F.R. § 1.31). The USPTO "always recommends" a registered practitioner, and its staff cannot give legal advice (Pro Se Assistance Program). Permission to file alone does not mean the Office will guide you through it.
What's current
As of November 6, 2026
Since July 20, 2026, the foreign-domicile rule applies to all papers received on or after that date, regardless of filing date. Applications without a practitioner signature still get a filing date, but an application data sheet signed by a foreign-domiciled inventor is treated as a transmittal letter, so priority and benefit claims are not effective (91 FR 13510).
Since September 11, 2025, every Patent Center user must be identity-verified, offered through ID.me, and guest access has ended (USPTO Patent Center). The alternative is paper, at a $400 / $200 / $200 fee (undiscounted, small, micro) (USPTO fee schedule). We did not confirm that every submission type can go on paper.
The Patent Pro Bono Program commonly requires household income under three times the federal poverty guidelines, with regional variation, plus demonstrated patent knowledge (USPTO, updated September 6, 2024).
Key takeaways
- A US-domiciled individual may still file without a practitioner.
- A company must be represented.
- Anyone domiciled outside the US must be represented, with no exception for mixed groups.
- The USPTO recommends a practitioner, and its staff cannot give legal advice.
Check your understanding
Sources
The Academy is general education, not legal advice, and reading it doesn't create an attorney-client relationship. Patent law and fees change, so check the linked sources and have a registered patent attorney or agent review your situation before you file. Obsidyan sells patent software, including AI drafting tools, so weigh what these lessons say about AI tools with that in mind.