What is a Provisional Patent Application?

Key Facts

• Statute: 35 U.S.C. § 111(b) and § 119(e)
• Lifespan: 12 months, not extendable; the priority claim can be restored for up to 2 further months by petition if the delay was unintentional
• Required contents: A specification and any drawings needed to understand the invention; claims, an oath or declaration, and an information disclosure statement are not required
• Examination: None. A provisional is never examined and never publishes on its own
• Fee: A few hundred dollars for a large entity, far below a non-provisional
• Term: The 12 months do not count toward the 20-year patent term

What a Provisional Actually Gives You

A provisional buys a filing date. Anything disclosed in it is protected against later filings by others and against the applicant's own later public disclosures, but only to the extent the provisional describes it. When the non-provisional is filed, each claim gets the provisional date only if the provisional supports that claim under the written description and enablement requirements of § 112. Claims that reach beyond the provisional get the later filing date.

This is the central pitfall. A two-page provisional written the night before a conference will support only what those two pages enable. Competitors' filings and the applicant's own talk become prior art against everything else.

The 12-Month Deadline

The provisional's only deadline is the one that matters most. Within 12 months the applicant must either:

1. File a US non-provisional application claiming the benefit of the provisional
2. File a PCT application claiming the provisional as a Paris Convention priority
3. File directly in foreign countries claiming Paris Convention priority
4. Let it lapse

Conversion is also possible under 37 C.F.R. § 1.53(c)(3), but converting makes the provisional filing date the start of the 20-year term, so nearly everyone files a new non-provisional instead.

Strategic Uses

• Disclosure deadline: Filing before a paper, trade show, or investor pitch preserves foreign rights, which are lost on public disclosure in most countries outside the US
• Serial provisionals: Filing updated provisionals as the invention matures, then claiming all of them in one non-provisional within 12 months of the first
• Budget deferral: Postponing the cost of drafting claims and the non-provisional fee while the market is tested
• Patent pending: A provisional permits the marking "patent pending" on products

Provisional Quality

Because a provisional's value depends entirely on its disclosure, invention disclosure quality upstream determines its worth. Structured invention disclosure capture that prompts inventors for alternatives, ranges, and variations produces provisionals that support broad claims a year later.