FORM UC-36 (REV. 09-2026)UCDP MANDATE: 2026-11-02
UADCHECKPre-submission inspection of UAD 3.6 packages

UAD1663

FATAL

Official message text · Appendix H-1: UAD Compliance Rules — URAR, v1.5

Indicate whether the present or the proposed use is the highest and best.

Fatal — a single unresolved Fatal makes the entire submission come back NOT SUCCESSFUL (UCDP Hard Stop 401).

What triggers UAD1663

The published rule logic, verbatim:

If SiteHighestBestUseIndicator is not provided

  • Checked for the Subject property.
  • • Bound to MISMO data point SiteHighestBestUseIndicator at ../VALUATION_ANALYSIS/PROPERTIES/PROPERTY/SITE/HIGHEST_AND_BEST_USE/

How to fix it

On the URAR, this lives at: Highest and Best Use → Is the highest and best use of the subject property as improved (or as proposed per plans and specifications) the present use?. Complete or correct that field in your form software, regenerate the package, and re-check before submission.

Because this is a Fatal edit, do not submit until it is resolved — one Fatal bounces the whole package.

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Related messages

Source: Appendix H-1: UAD Compliance Rules — URAR, v1.5 (public GSE document). Verified against the published spreadsheet; not affiliated with Fannie Mae or Freddie Mac.