Why this question is coming up more often
IP Australia's Australian IP Report 2026 shows provisional filings rising from 4,343 in 2024 to 6,867 in 2025, an increase of 58 per cent. Over the same period the share filed without a patent attorney jumped to 52 per cent, having sat between 19 and 27 per cent from 2021 to 2024. Close to two-thirds of 2025 provisionals came from people who had never filed a patent application before.
The report links part of this growth to cheaper drafting with digital tools, including AI, and it flags questions about the quality of what is being disclosed. That matches what we see. More and more inventors come to us having already filed a short description, often written with an AI tool (we look at the risks in can AI write your provisional patent application?), on the understanding that it "ticks the box" and that an attorney can tidy it up when the complete application is due. Unfortunately, that is rarely how it works.
What the $100 actually buys
For your $100 you get a filing date, an application number and the right to call your invention "patent pending". IP Australia checks the formalities, but it does not examine a provisional or decide whether it describes your invention adequately.
That assessment happens much later. Usually it is when the complete application is examined, often two or more years down the track, and sometimes not until a competitor challenges the patent in court. By then the provisional can't be changed, and whatever it failed to say stays unsaid.
What a provisional has to do
A provisional exists to secure your priority date. That is the date against which the novelty and inventive step of your invention are judged, so every publication, product and patent filing after it is disregarded when your claims are assessed.
Since the Raising the Bar reforms took effect in 2013, section 40(1) of the Patents Act 1990 requires a provisional specification to disclose the invention clearly enough and completely enough for it to be performed by a person skilled in the relevant field. The priority rules apply the same test claim by claim. A claim in your later complete application is entitled to the provisional's date only if the provisional disclosed that claimed invention to that standard.
In practical terms, a provisional that will hold up needs to do several things. It must describe the invention in enough technical detail for a skilled person to make and use it without further invention. It must describe each feature you may later want to claim, along with the reasonable variations of those features. And it should do this clearly enough that an examiner, years later, can find each claimed feature in the text without having to read between the lines. Under section 40(3), the claims of your complete application must be supported by what the specification discloses, so what is missing from the description generally can't be claimed with the early date.
IP Australia will accept a blank page for $100. Whether that page earns you a valid priority date is decided years later, by an examiner or a court.
When the cheap provisional fails
Here is the scenario that worries us most. An inventor files a brief provisional, then does what the provisional period is for: launches the product, runs a crowdfunding campaign or pitches to investors. Near the 12-month deadline they engage an attorney to prepare the complete application, and the attorney adds the technical detail and claims that were missing.
At examination, the examiner compares the claims against the provisional and finds that the key features were never properly disclosed in it. Those claims fall back to the filing date of the complete application. Everything published in the gap is now prior art against them: competitors' filings, journal articles, and potentially the inventor's own launch. Australia has a 12-month grace period for an inventor's own disclosures, but Europe and China, among others, do not, as we explain in patent grace periods country by country. We explain how this unfolds in more detail in our article on the pitfalls of a poorly prepared provisional patent application.
This is not a theoretical risk. In ToolGen Inc v Fisher (No 2) [2023] FCA 794, the Federal Court held that the claims of a CRISPR gene-editing application were not entitled to the date of the earliest priority document, because that document disclosed a narrower invention than the one later claimed. With the early date gone, intervening publications left the application without a valid claim. That applicant was well resourced and professionally advised. A one-page provisional is far more exposed.
Why saving on the provisional is a false economy
The provisional is the cheapest stage of the patent process, but everything that follows is built on it. PCT applications, national phase filings in each country and examination responses typically cost many times more than the provisional did. If the foundation is weak, that later money is spent on a patent whose key claims may be invalid from the start, and you may not find out until after it has been spent.
There is also a less obvious cost. A thin provisional gives your attorney little to work with when the examiner cites prior art. Without technical detail to fall back on, there may be nothing in the specification to amend towards, and an application that might have been rescued with a well-chosen amendment is lost instead.
What you are really paying for
When you engage a patent attorney to prepare a provisional, you are not paying for paperwork. You are paying for a document that secures a priority date you can rely on, for a defined set of claims, with enough detail behind them to survive examination in every country you later choose.
At Patentec we draft the claims first and then build the description around them. Our provisional specifications typically run to 20 to 50 pages of technical description supporting 20 or more claims, from broad to narrow. We explain why in can you prepare a patent application yourself? and set out the full process in our approach to patent applications.
If you have an invention and want to know what a properly prepared provisional would look like for it, contact us for a free initial consultation. We'll talk you through what needs to be in the specification and how to protect your priority date from the outset.