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Immaculate Constellation: Inside the Leaked UAP Dossier

By UFO Disclosure Files Editorial Desk Published Updated Reported claim

Executive Summary

The explosive controversy surrounding "Immaculate Constellation" centers on an alleged Unacknowledged Special Access Program (uSAP) within the Department of Defense designed to intercept, analyze, and quarantine high-resolution military sensor intelligence regarding Unidentified Anomalous Phenomena (UAPs). First published by investigative journalist Michael Shellenberger and authored by former national security policy analyst Matthew Brown, the 11-page dossier was formally entered into the Congressional Record by Representative Nancy Mace during the November 13, 2024 House Oversight Committee hearing. We examine the document's technical claims, the Pentagon's official denials, and its direct relevance to the 2026 PURSUE disclosure landscape.

The alleged Unacknowledged Special Access Program behind the leaked dossier

The emergence of Immaculate Constellation represents one of the most consequential whistleblower episodes in modern defense transparency. While the Department of Defense maintains that no past or present program exists under that name, congressional investigators and defense analysts have scrutinized the document's precise operational terminology, sensor architecture descriptions, and Title 10 legal compartmentalization. Evaluating the claims requires balancing sworn whistleblower disclosures against the absence of declassified material proof.

The leaked 11-page dossier and Michael Shellenberger's disclosure

In late 2024, investigative journalist Michael Shellenberger published a groundbreaking 11-page whistleblower dossier detailing an alleged covert program titled "Immaculate Constellation."

  • The document detailed a sophisticated military enterprise allegedly established to centralize intelligence on military encounters with anomalous craft.
  • According to the dossier, the program operated across military branches to intercept raw sensor feeds before they entered standard reporting channels.
  • Shellenberger testified before the House Oversight Committee that sources warned him simply uttering the program's codename could trigger automated counterintelligence surveillance.

Matthew Brown: Clearance background and whistleblower emergence

In early 2025, former national security policy analyst Matthew Brown publicly stepped forward as the author of the Immaculate Constellation report.

  • Brown held a Top Secret/SCI clearance and served in sensitive roles within the Office of the Secretary of Defense for Policy, specifically focusing on counter-proliferation and counter-WMD missions.
  • His security clearances granted him access to multi-sensor data collection arrays monitoring sensitive U.S. military bases, nuclear weapons storage facilities, and restricted airspace.
  • Brown stated he authored the document after observing systematic compartmentalization where high-resolution imagery and radar tracks of metallic orbs and triangle craft were removed from joint operational databases.

Rep. Nancy Mace and the November 2024 House Oversight hearing

The Immaculate Constellation dossier transitioned from an unauthorized leak to an official congressional matter on November 13, 2024.

  • During a joint hearing of the House Oversight subcommittees titled "Unidentified Anomalous Phenomena: Exposing the Truth," Representative Nancy Mace (R-SC) led inquiries into Pentagon secrecy.
  • In a widely broadcast Capitol Hill moment, Rep. Mace deliberately spoke the name "Immaculate Constellation" into the congressional record and entered the complete 11-page document as a formal committee exhibit.
  • Lawmakers questioned witnesses—including former Pentagon official Luis Elizondo and former Navy Rear Admiral Tim Gallaudet—regarding why unacknowledged programs bypass statutory congressional notification under 10 U.S.C. § 119.

Alleged architecture: Centralized IMINT, MASINT, and sensor isolation

The dossier provides a granular technical description of how Immaculate Constellation purportedly harvests and isolates multi-spectral data.

  • The program allegedly aggregates imagery intelligence (IMINT), measurement and signature intelligence (MASINT), and electronic intelligence (ELINT) from Navy, Air Force, and space-based platforms.
  • Advanced artificial intelligence algorithms were reportedly deployed to scan operational sensor feeds, detect anomalous kinematic trajectories, and extract raw files into isolated enclave servers.
  • This quarantine architecture prevented operational commanders and official oversight entities—such as AARO—from accessing primary sensor tapes and high-definition targeting pod video.

The Pentagon's official response: Denials and AARO historical review

The Department of Defense has maintained an unequivocal, categorical denial regarding the existence of Immaculate Constellation.

  • Pentagon spokesperson Sue Gough stated that the Department of Defense has "no record, present or historical, of any type of Special Access Program called Immaculate Constellation."
  • AARO's Historical Record Report Volume 1 similarly concluded that claims of hidden crash retrieval or illicit sensor-hoarding programs were based on circular rumors and misidentified classified military activities.
  • Critics argue that if the program is an Unacknowledged SAP or Waived SAP (WSAP), standard FOIA and public affairs offices would be legally prohibited from confirming its existence.

Evidentiary evaluation: Whistleblower declarations vs verified records

For defense analysts and researchers navigating the UAP disclosure controversy, assessing Immaculate Constellation requires rigorous epistemic discipline.

  • Matthew Brown's background and congressional submission provide significant qualitative credibility, demonstrating serious insider concern regarding data over-classification.
  • However, the 11-page dossier remains a secondary text: it does not contain cryptographic metadata, declassification stamps, or reproducible sensor files.
  • In the 2026 disclosure era under PURSUE, whistleblowers like Brown have petitioned the White House for executive immunity and declassification waivers to verify whether corresponding raw sensor files exist in federal vaults.

Key findings on Immaculate Constellation

  • The 11-page "Immaculate Constellation" dossier describes an alleged Unacknowledged Special Access Program (uSAP) dedicated to isolating high-resolution military UAP intelligence.
  • Matthew Brown, a former national security analyst who held TS/SCI clearance in the Office of the Secretary of Defense for Policy (counter-WMD), emerged as the author of the dossier.
  • Representative Nancy Mace formally entered the whistleblower report into the Congressional Record during the November 13, 2024 House Oversight hearing.
  • The Department of Defense (DoD) officially denied the program's existence, stating it has no record of any past or present SAP under that name.
  • In the 2026 disclosure landscape, whistleblowers continue petitioning the White House for declassification immunity to release unredacted sensor telemetry under the PURSUE framework.

Read next

How to analyze leaked whistleblower claims alongside official denials

The strongest reading starts with the primary record, then follows the supporting documents, dates, agency labels, and public statements around it. When commentary or reporting adds context, it is weighed against the source record instead of being treated as the record itself.

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