US college web census · gap lists · census 2026-09-30 · JSON (top 50) · feed
Colleges with an expired security.txt
14 of the 4,961 colleges in the census list (0.3%; 0.3% of the 4,763 reachable over HTTPS), as fetched on 2026-09-30.
On this list
14
of 4,961 colleges
Share of the list
0.3%
0.3% of reachable sites
States
10
largest: Nebraska (3)
Full list
1.00 USDC
x402, per file; first 50 rows free
What this gap means
A security.txt is published but its Expires date has passed; RFC 9116 says a file past that date should not be relied on.
Control: security.txt Expires line (RFC 9116). Rule: expired_security_txt over the census record (reachable sites only). Who buys this: Security teams and vulnerability-disclosure vendors: a lapsed file is a specific, verifiable conversation opener.
The obligation it maps to
RFC 9116 security.txt: The security.txt standard defines the /.well-known/security.txt location and requires Contact and Expires fields so researchers can report vulnerabilities; the census marks a file complete when both are present and unexpired. Source
By state
10 states with at least one college on this list; "of the state" is the share of its colleges in the census list. One state as CSV: 0.25 USDC (x402).
| State | On this list | Of the state | CSV (x402) |
|---|---|---|---|
| Nebraska (report) | 3 | 7.5% | https://colleges.agentexchange.work/leads/expired-security-txt/state/NE.csv · card $9 |
| Texas (report) | 3 | 1.0% | https://colleges.agentexchange.work/leads/expired-security-txt/state/TX.csv · card $9 |
| Florida (report) | 1 | 0.4% | https://colleges.agentexchange.work/leads/expired-security-txt/state/FL.csv · card $9 |
| GU | 1 | — | https://colleges.agentexchange.work/leads/expired-security-txt/state/GU.csv · card $9 |
| Hawaii (report) | 1 | 4.3% | https://colleges.agentexchange.work/leads/expired-security-txt/state/HI.csv · card $9 |
| Indiana (report) | 1 | 1.3% | https://colleges.agentexchange.work/leads/expired-security-txt/state/IN.csv · card $9 |
| New Jersey (report) | 1 | 0.9% | https://colleges.agentexchange.work/leads/expired-security-txt/state/NJ.csv · card $9 |
| Pennsylvania (report) | 1 | 0.4% | https://colleges.agentexchange.work/leads/expired-security-txt/state/PA.csv · card $9 |
| West Virginia (report) | 1 | 1.6% | https://colleges.agentexchange.work/leads/expired-security-txt/state/WV.csv · card $9 |
| WY | 1 | — | https://colleges.agentexchange.work/leads/expired-security-txt/state/WY.csv · card $9 |
Free: the first 14 of 14
| Domain | Control and level | State | IPEDS sector | Census record |
|---|---|---|---|---|
| hilo.hawaii.edu University of Hawaii at Hilo | public 4-year | HI | Public, 4-year or above | HTTP 200 · HSTS yes · security.txt expired · privacy no · accessibility no · GPTBot partly blocked |
| lccc.wy.edu Laramie County Community College | public 4-year | WY | Public, 4-year or above | HTTP 200 · HSTS no · security.txt expired · privacy yes · accessibility yes · GPTBot partly blocked |
| princeton.edu Princeton University | private nonprofit 4-year | NJ | Private not-for-profit, 4-year or above | HTTP 403 · HSTS no · security.txt expired · privacy no · accessibility no · GPTBot partly blocked |
| pvamu.edu Prairie View A & M University | public 4-year | TX | Public, 4-year or above | HTTP 200 · HSTS no · security.txt expired · privacy no · accessibility no · GPTBot allowed |
| tamu.edu Texas A&M University-College Station | public 4-year | TX | Public, 4-year or above | HTTP 200 · HSTS yes · security.txt expired · privacy yes · accessibility yes · GPTBot allowed |
| tamus.edu Texas A & M University-System Office | public 4-year | TX | Administrative Unit | HTTP 200 · HSTS no · security.txt expired · privacy yes · accessibility yes · GPTBot partly blocked |
| tsc.fl.edu Tallahassee State College | public 4-year | FL | Public, 4-year or above | HTTP 200 · HSTS yes · security.txt expired · privacy yes · accessibility yes |
| unk.edu University of Nebraska at Kearney | public 4-year | NE | Public, 4-year or above | HTTP 200 · HSTS no · security.txt expired · privacy yes · accessibility yes |
| unl.edu University of Nebraska-Lincoln | public 4-year | NE | Public, 4-year or above | HTTP 200 · HSTS no · security.txt expired · privacy yes · accessibility yes · GPTBot partly blocked |
| unomaha.edu University of Nebraska at Omaha | public 4-year | NE | Public, 4-year or above | HTTP 200 · HSTS yes · security.txt expired · privacy yes · accessibility yes · GPTBot partly blocked |
| uog.edu University of Guam | public 4-year | GU | Public, 4-year or above | HTTP 200 · HSTS yes · security.txt expired · privacy yes · accessibility yes |
| villanova.edu Villanova University | private nonprofit 4-year | PA | Private not-for-profit, 4-year or above | HTTP 200 · HSTS yes · security.txt expired · privacy yes · accessibility yes · GPTBot partly blocked |
| vinu.edu Vincennes University | public 4-year | IN | Public, 4-year or above | HTTP 200 · HSTS yes · security.txt expired · privacy yes · accessibility no · GPTBot partly blocked |
| westliberty.edu West Liberty University | public 4-year | WV | Public, 4-year or above | HTTP 200 · HSTS no · security.txt expired · privacy yes · accessibility no · GPTBot partly blocked |
The same rows as JSON: expired-security-txt.top.json (CORS open, cached one day).
Get the full list: 14 rows, 1.00 USDC
x402 on Base, paid per file, no account or key. GET https://colleges.agentexchange.work/leads/expired-security-txt.csv or GET https://colleges.agentexchange.work/leads/expired-security-txt.json answers 402 Payment Required with the terms (scheme exact, USDC on Base, maxAmountRequired 1000000, payTo 0xc91cE6291eDC0713ec753BAFBA002506ffb2b95c); an x402 client signs the EIP-3009 authorization and resends the same request with X-PAYMENT; the file comes back with a PAYMENT-RESPONSE header. HEAD gets the same 402. One state: GET https://colleges.agentexchange.work/leads/expired-security-txt/state/<code>.csv, 0.25 USDC (codes in the table above).
curl -sS -D - https://colleges.agentexchange.work/leads/expired-security-txt.csv # 402 with the x402 terms; pay and resend with X-PAYMENT
Columns (19): domain, name, type, city, state, ipeds_sector, reachable, http_only, https_status, final_host, hsts, security_txt, privacy_link, accessibility_link, robots_gptbot, robots_chatgpt_user, robots_claude_user, llms_txt, title. CSV: header row, every cell quoted, yes/no for booleans. JSON: { list, title, count, by_state, columns, rows[][] }. Sizes: CSV 4 KB, JSON 5 KB. The same facts are in the free CC BY 4.0 dumps: the price buys the filtered, state-sliceable file built from the 2026-09-30 census, not exclusive data. Settlement is final; no refunds. Prices in /.well-known/x402 equal the challenges. Terms · pricing.
Card checkout
Pay with a card through Stripe and get the file on the next page: Full list CSV, $29 · JSON, $29 · one state $9 (links in the table below) · all 8 lists, $79. Agents pay less with x402 (see above).
Monitor this list (free)
Atom feed: colleges that entered or left this list according to the live re-checks (every 6 hours a rotating slice, each domain at most once per 14 days; each entry says which way it moved and which field changed). expired-security-txt.top.json: the first 14 rows and the counts by state as JSON, CORS open. Fields watched: security_txt, security_txt.expired.
Membership reflects the homepage and well-known files as fetched on 2026-09-30: a control that exists but was not found where the census looked counts as missing, and sites answering 403 to our one polite request count as reachable. Every domain links to its record with what to fix, a JSON twin, a badge and a changes feed. Data licence CC BY 4.0. Not legal advice.