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OSINT (open-source intelligence)
OSINT, open-source intelligence, is the practice of collecting and analysing information from publicly available sources: websites, social media, public records, images, maps and news. In the image domain it includes reverse image search, face search, geolocation from photo details and metadata analysis. It is used by journalists, investigators, researchers and, with the same tools, by people with harmful intent.
Updated November 6, 2026 · 2 min read
What counts as an open source?
Anything accessible without hacking or deception: public web pages, public social profiles, government registers, court records, satellite imagery, archived pages, leaked data that has already been published. The public web that face search engines index is one slice of it. Content behind a login that the investigator has legitimate access to is a grey area most codes of practice treat as closed.
What are the image techniques?
- Reverse image search to find earlier publications of the same picture and date it.
- Reverse face search to find other photos of the same person on public pages.
- Geolocation from shadows, signage, vegetation, vehicles and architecture, cross-checked against maps and street imagery.
- EXIF metadata where it survives: camera, time, sometimes GPS. Most platforms strip it.
- Chronolocation: sun position and weather records to fix the time a photo was taken.
Who uses it?
Investigative outlets such as Bellingcat built their reputation on image OSINT, verifying war footage and identifying perpetrators from open sources. Fraud teams, insurers, lawyers, human-rights monitors and missing-persons groups use the same methods. So do stalkers and harassers, which is why the techniques are neutral and the use is not: the ethics live in the purpose, the proportionality and what is done with a finding.
What are the rules?
| Constraint | What it means in practice |
|---|---|
| Data-protection law | Processing a face is processing biometric data in the EU and UK; a lawful basis is needed even for public photos (see GDPR) |
| Platform terms | Scraping and automated collection usually breach terms of service even when the data is public |
| Corroboration | A face match is a lead. Professional codes require a second, independent source before naming anyone |
| Harm review | Publishing a finding about a private person needs a public-interest reason; most newsroom guides say so explicitly |
Where does face search fit?
Face search is the fastest OSINT technique and the easiest to misuse. The doppelganger effect makes confident wrong identifications common; the 2013 Boston Marathon case, where online sleuths named innocent people, is the standard warning. Engines document their rules in their own terms; the engines index lists each one's stated acceptable use.
Questions
Is OSINT legal?
Collecting public information is lawful in most places. What you do with it is governed by data-protection, harassment, stalking and defamation law, and by platform terms. Identifying a private person from a face match and publishing it is where most legal risk sits.
Is face search part of OSINT?
Yes, as one technique among many. Practitioners treat a match as a hypothesis to test against other sources, never as an identification on its own.
Sources
- 1.Bellingcat, Resources: guides and tools for open source research (checked November 6, 2026)
- 2.Berkeley Protocol on Digital Open Source Investigations (OHCHR and UC Berkeley Human Rights Center) (checked November 6, 2026)
Entry reviewed November 6, 2026. Found an error? Tell us.
Related entries
- Term Reverse image search Reverse image search defined: searching the web with a picture as the query, what it finds (copies, crops, edits), the main engines, and why it is not a face search.
- Term Reverse face search Reverse face search defined: a query by face rather than by image file, how it differs from reverse image search, what a result contains, and which engines offer it.
- Term EXIF metadata EXIF metadata defined: the camera, time and location data embedded in photo files, what it can reveal, which platforms strip it, and how to remove it before sharing.
- Term Doppelganger effect The doppelganger effect: why a face search returns look-alikes, how index size and photo quality make it worse, and how to verify a match with non-face evidence.
- Law General Data Protection Regulation (GDPR) and biometric data GDPR and face search: Article 9 biometric data, the household exemption, territorial reach under Article 3(2), fines up to 4%, and the Clearview and PimEyes cases.
Cite this entry
FaceSearch Wiki editors. "OSINT (open-source intelligence)". FaceSearch Wiki, updated November 6, 2026. https://facesearch.wiki/glossary/osint/