Engineering drawings — including CAD files, schematics, and design documents — can help support R&D tax credit documentation. This page explains how drawings can support a credit claim. It is educational and is not individualized advice. For the general documentation concepts, see our page on R&D tax credit documentation.
How Drawings Support the Business Component
Engineering drawings can help identify and describe the business component — the product, process, or component being developed or improved. Drawings that show what the business component is and how it is configured can help connect activities and costs to a specific business component. For more, see our page on qualified research.
How Drawings Support the Uncertainty Element
Drawings can help support the elimination-of-uncertainty element by showing what was uncertain about the design. Drawings that show alternative designs, dimensions marked "to be determined," or design iterations can help demonstrate that there was a technical uncertainty about the appropriate design. For more, see our page on elimination of uncertainty.
How Drawings Support the Alternatives Element
Drawings can help support the process-of-experimentation element by showing the alternatives that were evaluated. Multiple drawings showing alternative designs, configurations, or approaches can help demonstrate an evaluative process of alternatives. For more, see our page on process of experimentation.
How Drawings Support the Iteration Element
Drawing revisions and version histories can help show the iteration process — how designs changed in response to testing and evaluation. Revision histories that show what changed and why can help demonstrate a genuine evaluative process.
Contemporaneous Drawings Are Most Useful
Drawings created during the development process — contemporaneous drawings — tend to be more useful than drawings reconstructed after the fact. Contemporaneous drawings reflect what was actually being evaluated at the time and tend to be more persuasive.
Hypothetical Example
Consider a manufacturer that is developing a new product and has CAD files showing the initial design, alternative designs that were evaluated, dimensions marked "to be determined," and revision histories showing how the design changed in response to testing. These drawings can help support the business component, the uncertainty, the alternatives, and the iteration elements.
By contrast, a single final drawing with no alternatives or revisions is less useful for supporting the experimentation element.
These examples are illustrative only.
Key Takeaway
Engineering drawings can help support R&D tax credit documentation by showing the business component, design alternatives, and iterations. Drawings are most useful when they are contemporaneous and connected to specific projects. Because documentation adequacy is fact-specific, professional review is appropriate.