Start here: the four-part test
The four-part test is the threshold check every claimed business component must clear.
Dig deeper: the 11-question rubric
Each question scores a single dimension of the four-part test for a single business component.
- Q1a: Identify the specific business component being developed or improved.
- Q1b: Which of the four qualifying dimensions does the work target?
- Q1c: Confirm the work is not purely stylistic, cosmetic, or seasonal.
- Q2a: Name the hard-science discipline(s) the work draws upon.
- Q2b: Cite at least one principle, algorithm, or technique from that discipline applied here.
- Q3a: What was unknown at the outset (capability, method, or appropriate design)?
- Q3b: Was the answer publicly known or trivially obtainable from a single source?
- Q3c: Who held the uncertainty (the company, the engineering lead, the team)?
- Q4a: List the alternatives evaluated.
- Q4b: Cite at least three iteration cycles (commit, test, observe, refine).
- Q4c: Confirm at least 80% of the time recorded against this component is experimentation, not setup, deployment, or admin.
Filing: Form 6765 Section G (mandatory tax year 2026)
Section G is the per-business-component schedule on Form 6765. R&D Binder produces all nine fields, mapped column-for-column.
Define the terms: the Section 41 glossary
Plain-English definitions of the terms that decide a claim, each grounded in primary authority and citing at least three independent sources.
- Qualified Research Expense (QRE)
- Business Component
- Qualified Small Business (QSB) Payroll-Tax Offset
- Form 6765
- Alternative Simplified Credit (ASC)
- Contemporaneous Documentation
- Qualified Research Activity (QRA)
- Section 174A
- Internal-use software (IUS)
- Contract research expenses
- Funded research
- Substantially-all (80%) rule
- Section 174
- Section 280C election
Who the R&D credit is for
How the Section 41 credit applies to specific kinds of company.
Compare your options
Side-by-side breakdowns of the choices that change your credit.
State R&D credits
Many states stack their own research credit on the federal one. Each guide pairs the state rules with the federal Section 41 work.
Get documentation built to survive an exam
When you are ready, see the sample binder to see how all of this lands in a real document, or estimate your credit.