The Sixtyfour blog
Field briefs and case studies on identity resolution, fraud rings, and what our agents find.
Trust & SafetyWhat is identity resolution, and how does it work?
Deciding whether separate records belong to the same person is an old statistical problem. How the method works, what each identifier is evidence of, the two errors that matter, and how to write a match down so someone else can check it.
Saarth ShahCo-Founder & CEO
Trust & SafetyHow to tell if a job reference is fake
The candidate chooses the referee and supplies the contact details. How to check that a referee is real, reach them through a channel you found yourself, and read what an email address and a phone number say.
Hashim KhawajaFounding Engineer
Trust & SafetyMoney mule red flags: how to spot mule accounts
A mule account looks ordinary until you look at how money moves through it and who holds it. The account patterns investigators describe, how mules are recruited, and the research on the holder that helps tell a victim from a willing part of the scheme.
Julian WongHead of Trust & Safety
Trust & SafetyHow to find out who owns an LLC
A state registry often shows little more than that an LLC was formed and who receives its legal papers. Where the names of its members and managers turn up, in its filings, deeds, liens, licences and footprint, and what each record proves.
Roham MehrabiHead of Growth
Trust & SafetyHow to verify a vendor before you pay them
A real supplier can be impersonated and a fake one can look real. The checks that separate them, what each one proves, why a change of bank details is the moment to stop, and what to do if the money has already gone.
Roham MehrabiHead of Growth
Trust & SafetyHow to tell if a LinkedIn profile is fake
A polished profile proves little. How to read a profile's age, badges, history and photo, look for the person outside LinkedIn, and weigh what each check is evidence of.
Julian WongHead of Trust & Safety
ProductThe new Sixtyfour search, tested on Exa's own benchmarks
Sixtyfour search now puts a match first on 90.4% of the queries in Exa's people search benchmark, ahead of every published result.
Yahia SalmanSixtyfour Research
Trust & SafetyHow to run an OSINT investigation
One case from the first question to the written report: how to scope it, pivot between identifiers, weigh each link, preserve the evidence and say how sure you are.
Saarth ShahCo-Founder & CEO
Trust & SafetyHow to find out who owns a website
Most registration records now hide the owner. The pivots that still work, what each one is evidence of, and how to tell today's operator from a domain's earlier owners.
Hashim KhawajaFounding Engineer
Trust & SafetyHow to verify a resume: employment history, degrees and licences
Job seekers stretch claims more often than they invent them. How to check each claim against a record the candidate did not write, and what a mismatch can mean.
Julian WongHead of Trust & Safety
Trust & SafetyShell company red flags: how to check and weigh each one
A crowded address or a busy director proves little on its own. What each red flag is evidence of, how to check it against a primary source, and what it means when several agree.
Roham MehrabiHead of Growth
Trust & SafetyHow to investigate a phone number
Reports often arrive with nothing but a phone number. What it can prove, how to date it, and why today's holder may not be the one you want.
Hashim KhawajaFounding Engineer
Trust & SafetyAdverse media screening: how to review a hit
Many adverse media hits are about someone else, and many of the rest need context. How to resolve a hit, read what it alleges, and record the decision.
Roham MehrabiHead of Growth
Trust & SafetyHow to evaluate AI tools for investigations
AI research agents can take on much of an investigation's legwork. Five checks tell you whether their results will hold up when someone asks how you know.
Saarth ShahCo-Founder & CEO
Trust & SafetyHow to link related accounts in a trust and safety investigation
Shared IPs, devices and cards connect accounts, and they also connect strangers. How to weigh each link, and when a cluster is really one operator.
Julian WongHead of Trust & Safety
Trust & SafetyKYB verification: checking a business is real, not just registered
A KYB check can confirm that a company was registered. The harder part is showing that it trades, who controls it, and that the bad news you found is about it.
Roham MehrabiHead of Growth
Trust & SafetyHow to detect synthetic identity fraud
A synthetic identity passes KYC because every piece of it checks out. What it usually lacks is the past a real person builds up without trying.
Julian WongHead of Trust & Safety
Trust & SafetyHow to investigate an email address
An email address is often the only identifier a report arrives with. Here is what it can tell you, the order to read it in, and where it misleads.
Saarth ShahCo-Founder & CEO
Trust & SafetyHow to spot fake candidates before the interview
Interviews test whether someone can do the job. A constructed identity usually can.
Julian WongHead of Trust & Safety
EngineeringBest Exa alternatives for AI agents in 2026
Eight alternatives compared across search, live fetching, browser automation, and cost at volume.
Hashim KhawajaFounding Engineer
CompanyInside Sixtyfour: how we operate
Twelve principles we actually run on — plus the 120lb flat cart that explains all of them.
Justin YoungOperations
Trust & SafetyReverse username search: tracing one handle across platforms
Bad actors hide behind pixelated avatars and disposable handles. Here is how the chain unravels.
Hashim KhawajaFounding Engineer
Trust & SafetyIdentity resolution: catching banned users who rotate hardware
Device fingerprinting works on the bottom 90% of operators, but the top 10% rotate hardware before breakfast. Here is how to stop them.
Saarth ShahCo-Founder & CEO
Trust & SafetyHow to detect rented gig-worker accounts
A $65 Facebook transaction is all it takes to put an unvetted stranger behind the wheel. Here's how Sixtyfour closes that gap.
Hashim KhawajaFounding Engineer, Sixtyfour
Trust & SafetyBeneficial ownership: tracing who is behind a shell company
In 2024, TD Bank pleaded guilty to $18.3 trillion in unmonitored transaction activity tied to money laundering. Here is how agents trace the beneficial owners behind shell networks.
Roham MehrabiHead of Growth
CompanySixtyfour AI is now backed by Y Combinator
Sixtyfour AI is joining Y Combinator’s first-ever spring batch as we go all in on building the best AI research platform in the world.
Saarth ShahCo-founder