Chain of custody receipt

Source #5443

Cryptographic attestation that the document below was captured in Goblin House's archive at the timestamp shown, with the hash listed. If the original URL goes dark or its content changes, this receipt remains as evidence of what the public record looked like at capture time.

Title	IRS Form 990: Hyper Igm Foundation — 2019 (EIN: 47-4048626)
Original URL	https://projects.propublica.org/nonprofits/download-filing?path=download990pdf_10_2021_prefixes_45-48%2F474048626_201912_990_2021101519103405.pdf
Publication	IRS Form 990 via ProPublica Nonprofit Explorer
Source type	`form_990`
Date	2019
Entity	Hyper Foundation
Captured	2026-04-12T17:40:44.279Z UTC
Hash computed at	2026-04-12T17:40:44.279Z UTC
SHA-256	`fc400d7641f45dc2b52c2203106205d09300acc7c1e2e12baa1b6c6907346c49`
Content length	2,930 bytes

Content preview (first 800 chars)

{
  "organization": {
    "id": 474048626,
    "ein": 474048626,
    "name": "Hyper Igm Foundation",
    "careofname": "% AKIVA ZABLOCKI",
    "address": "680 WEST END AVE STE 12D",
    "city": "New York",
    "state": "NY",
    "zipcode": "[ZIP+4 redacted]",
    "exemption_number": 0,
    "subsection_code": 3,
    "affiliation_code": 3,
    "classification_codes": "1280",
    "ruling_date": "2015-06-01",
    "deductibility_code": 1,
    "foundation_code": 15,
    "activity_codes": "000000000",
    "organization_code": 1,
    "exempt_organization_status_code": 1,
    "tax_period": "2024-12-01",
    "asset_code": 4,
    "income_code": 3,
    "filing_requirement_code": 1,
    "pf_filing_requirement_code": 0,
    "accounting_period": 12,
    "asset_amount": 391854,
    "income_amount"…

Verifying this receipt

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sha256( coalesce(url, '<no-url>') || '\n' || raw_content )

Anyone with a copy of the original document can verify the match:

Take the URL field and the original document content.
Concatenate url + '\n' + content and SHA-256 it.
Compare to the SHA-256 row above.

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curl -X POST https://www.goblinhouse.net/source/5443/verify \
  -H "Content-Type: text/plain" \
  --data-binary @document.txt

Companion machine-readable receipt: /source/5443/receipt.json