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IRS Guidance & Revenue Procedures
Official IRS rules and procedural guidance
Reference↗ External
Rev. Proc. 2025-28 — OBBBA Implementation Guidance
Comprehensive IRS guidance for §174A elections, method changes, small business retroactivity, §280C elections, and transition rules. Issued August 28, 2025.
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Legislation↗ External
Treasury Regulations §1.41 Series
The foundational Treasury regulations governing the §41 R&D credit — QREs, qualified research, controlled group rules (§§1.41-2, 1.41-4, 1.41-6, 1.41-7).
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Reference↗ External
IRS Research Credit Central Hub
The IRS's landing page for all R&D credit guidance — links to notices, revenue procedures, ATGs, Form 6765 resources, and FAQs.
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FAQ↗ External
IRS FAQs: Research Credit Claims on Amended Returns
Official IRS answers on the five required items, 45-day perfection window, and when claims may be rejected.
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