How to Account for Patent Costs: What You Capitalize, How Amortization Works, and When to Write Off a Dead Patent

You just paid a patent attorney $18,000 to draft and file a utility patent application, plus another $800 in USPTO fees. Your instinct says to deduct the whole $18,800 on this year's tax return and move on — but if you do, you will overstate this year's expenses, understate your assets, and create a mismatch your CPA has to unwind later. Patent costs sit exactly on the line between "expense it now" and "capitalize it and amortize," and the line runs through the middle of your legal bills: the research that produced the invention is expensed, while the legal and filing costs that turned it into a registered property right go on the balance sheet. Get the split right once, and every future filing follows the same template.

The Core Rule: Research Is Expensed, Registration Is Capitalized​

Under U.S. GAAP, the accounting for a self-developed patent follows one dividing principle:

• Expense as incurred: everything spent to create the invention — engineer salaries, prototypes, materials, testing, and the failed experiments that came first. These are research and development costs under ASC 730, and they hit the income statement in the period you spend them, because at the time you spend them there is no identifiable asset with a certain future benefit.
• Capitalize as an intangible asset: the direct costs of securing the legal right — USPTO filing, search, and examination fees, attorney fees for drafting the application and answering office actions (the examiner's rejections and queries), technical drawings, and the issue fee when the patent is granted. These costs attach to a specific, identifiable asset: the patent itself.

ASC 350 states the general version of this rule: costs of internally developing intangible assets that are not specifically identifiable are expensed, while registration and legal costs tied to a specific intangible are capitalized. Think of it as a timeline. Everything before you decide to pursue the patent is R&D. Everything from the patent attorney's first drafting invoice onward builds the asset on your balance sheet.

If you buy a patent from someone else instead of developing it, the treatment is simpler: capitalize the purchase price plus direct acquisition costs such as legal fees for the transfer. There is no R&D question because you bought a finished property right.

Which Patent Costs Go on the Balance Sheet​

Here is the practical split for a typical small-business filing:

Capitalize (debit to a Patent asset account):

• USPTO filing, search, and examination fees for the application
• Patent attorney fees for drafting the application and responding to office actions
• Technical drawings and figures prepared for the filing
• The USPTO issue fee when the patent is granted
• The purchase price of an acquired patent, plus transfer legal fees
• Legal costs of successfully defending the patent against infringement or a validity challenge

Expense in the current period:

• All R&D: salaries, contractor time, prototypes, lab materials, testing
• Legal costs of an unsuccessful defense — if the patent is invalidated or the challenge fails, the spending bought no future benefit
• Patent maintenance fees, due at 3.5, 7.5, and 11.5 years after grant — these maintain an existing right rather than creating or extending one, so standard practice expenses them as incurred
• Costs accumulated for an application that is ultimately denied or abandoned (more on the write-off below)

The successful-versus-unsuccessful defense distinction trips people up, so dwell on it for a moment. When you win an infringement suit or beat back a validity challenge, your legal spending protected the patent's future cash flows — that is textbook grounds for capitalization, and the capitalized amount is amortized over the patent's remaining life. When you lose, the spending produced nothing durable, so it is a period expense. Same invoices, opposite treatment, decided entirely by the outcome.

What the government fees actually run​

For budgeting purposes, a small business usually qualifies for small-entity USPTO pricing (under 500 employees), which cuts most fees roughly 60 percent below the large-entity rate. The combined filing, search, and examination fees for an electronically filed utility application run about $800 at the small-entity rate and about $400 at the micro-entity rate for qualifying independent inventors. Issue fees and the three maintenance windows add several thousand more over the patent's life. Attorney drafting and prosecution fees are separate and almost always the larger number — budget five figures for a professionally drafted utility application. Always confirm the current schedule before you file, since the USPTO adjusts fees periodically.

How Patent Amortization Works​

Once capitalized, a patent is amortized — the intangible-asset equivalent of depreciation — on a straight-line basis over its legal life or its useful (economic) life, whichever is shorter.

• The legal life of a U.S. utility patent is 20 years from the filing date. (Design patents run 15 years from grant.)
• The useful life is how long the patent will actually generate economic benefit for your business. A manufacturing process patent might earn for the full 20 years; a smartphone-feature patent superseded every three product cycles might have a realistic life of six.

When the two differ, the shorter one wins. A $24,000 capitalized patent with a 12-year expected useful life produces $2,000 of amortization expense per year ($24,000 divided by 12), not $1,200 over 20 years. Stretching amortization to the legal maximum when the technology will be obsolete in half that time overstates both your assets and your profits.

Amortization starts at grant, not at filing​

Application-phase costs accumulate in a patent-pending account while the USPTO examines the application — a process that routinely takes two to three years. Only when the patent is granted (placed in service) do you reclassify the balance to the patent asset and begin amortizing. If the application is denied, there is no asset to amortize, and the accumulated costs are written off immediately.

In a plain-text ledger, the lifecycle looks like this:

2026-02-10 * "Patent attorney - widget application drafting"
  Assets:Intangible:Patents:Patent-Pending:Widget  12,000.00 USD
  Assets:Checking  -12,000.00 USD
 
2026-02-10 * "USPTO filing, search, examination fees - widget application"
  Assets:Intangible:Patents:Patent-Pending:Widget  800.00 USD
  Assets:Checking  -800.00 USD
 
2028-05-01 * "Widget patent granted - reclassify to issued patent"
  Assets:Intangible:Patents:Widget-Issued  12,800.00 USD
  Assets:Intangible:Patents:Patent-Pending:Widget  -12,800.00 USD
 
2028-05-31 * "Amortize widget patent - May (12,800 over 10 years)"
  Expenses:Amortization:Patents  106.67 USD
  Assets:Intangible:Patents:Widget-Issued  -106.67 USD

The separate patent-pending subaccount is the whole trick: it keeps ungranted applications visible and makes the grant-or-deny decision a single reclassification entry. If you track more than one filing, give each its own subaccount so a denied application can be written off without touching the others. The Beancount documentation covers subaccount structures like this in detail.

The Tax Side: Section 167, and When Section 197 Takes Over​

Book treatment and tax treatment rhyme but follow different statutes.

Self-created and separately acquired patents: Section 167. For federal tax purposes, the basis of a patent is recovered ratably — straight-line — over its remaining useful life, under Treasury Regulation 1.167(a)-14. In practice this usually mirrors your book amortization, though the tax "useful life" is its own determination and the amortization period begins when the patent is placed in service — that is, granted and available for use. Keep the two schedules reconciled but separate; they can legitimately differ.

Patents acquired as part of buying a business: Section 197. When a patent comes to you bundled inside an asset acquisition or business purchase, it falls under Section 197's 15-year straight-line amortization instead — the same 15-year clock that covers goodwill, customer lists, and non-competes acquired the same way. This is the single most common tax-side error with patents: applying the 20-year patent life to an asset the Code says to write off over 15. If you bought the whole company, check Section 197 before Section 167.

Research spending itself is a third track. The R&D costs you expensed for book purposes are governed for tax by Section 174's research and experimental expenditure rules — a separate regime from the patent-registration costs this post covers. Congress has revisited those rules in recent years, so confirm the current treatment with your CPA rather than assuming book and tax agree.

When to Write Off an Abandoned or Worthless Patent​

Patents die before they expire all the time: applications are denied, maintenance fees go unpaid, technology moves on, courts invalidate claims. Each kind of death has an accounting consequence.

Denied or abandoned application. The moment you stop pursuing the application — final rejection, express abandonment, or simply letting it go — expense the full accumulated balance in the patent-pending account. There is no asset left to carry.

Granted patent that becomes worthless. Under GAAP, test the carrying amount for impairment when indicators appear (a competing technology, a lost licensee, an invalidity ruling), and write the asset down to fair value — often zero. Economically abandoning the patent by skipping a maintenance fee is the clearest possible indicator: you have told the world the remaining exclusivity is worth less than the fee, so the carrying amount should not survive that decision.

The tax deduction follows the same event. Treasury Regulation 1.167(a)-14 provides that if a patent becomes valueless in any year before its legal expiration, the adjusted basis may be deducted in that year. Document the event — the abandonment notice, the final rejection, the memo explaining why the technology has no further use — because "valueless" is a facts-and-circumstances call and the paper trail is what sustains it.

2029-03-15 * "Abandon widget patent - technology superseded, write off carrying amount"
  Expenses:Loss:Abandoned-Patent  11,413.29 USD
  Assets:Intangible:Patents:Widget-Issued  -11,413.29 USD

Run the write-off through a distinct loss account rather than burying it in amortization expense. A reader of your income statement should be able to see that a one-time abandonment, not recurring amortization, moved the number.

Six Mistakes That Misstate Patent Costs​

1. Expensing the drafting and prosecution fees. The attorney invoices feel like professional services, but they built the asset. Capitalize them.
2. Capitalizing the R&D. Engineer salaries, prototypes, and testing belong in the period they were spent, no matter how directly they led to the invention.
3. Amortizing over 20 years by default. Twenty years is the legal ceiling, not the schedule. Match the amortization period to the technology's realistic earning life.
4. Starting amortization at filing — or never starting it. Costs sit unamortized in patent-pending until grant, and amortization begins when the patent issues. Both directions of this error are common.
5. Capitalizing maintenance fees. They preserve the asset; they do not create or extend it. Expense them when paid.
6. Using Section 167 for a patent bought with a business. Bundle acquisitions run on Section 197's 15-year clock. Check how the patent arrived before picking the statute.

A Month-End Checklist for Patent Costs​

• New legal or USPTO invoice? Code it to the right filing's patent-pending subaccount — or to R&D expense if it predates the decision to pursue the patent.
• Patent granted this month? Reclassify patent-pending to the issued-patent account and start the amortization schedule.
• Any filing denied, abandoned, or impaired? Write off the balance now, with a memo documenting why.
• Maintenance fee window approaching? Calendar the due date, and expense the fee when paid.
• More than one filing? Confirm each subaccount reconciles to its own schedule before you close.

Patent accounting rewards one habit above all: keeping each filing's costs in their own bucket from the first invoice. Do that, and every later decision — capitalize or expense, amortize over what life, write off when — becomes a small entry instead of a reconstruction project.