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Physical Security for Bitcoin Holders

Cryptography can't protect you from physical threats.

The Uncomfortable Truth

No amount of technical security helps if someone threatens you or your family. Physical security is about preventing that situation and having options if it occurs.

The $5 Wrench Attack​

The famous "$5 wrench attack" illustrates a harsh reality:

CRYPTOGRAPHIC SECURITY
══════════════════════════════════════════════════════════════
Advanced encryption protects your Bitcoin from digital attacks.
Breaking it would take longer than the age of the universe.

$5 WRENCH ATTACK
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Someone threatens you with physical harm until you transfer
your Bitcoin. Works immediately.

The point: Your security model must account for physical threats, not just digital ones.

Prevention First​

The best physical security is preventing attackers from knowing you're a target.

Don't Advertise​

  • No Bitcoin merchandise (shirts, hats, stickers)
  • No car stickers or license plate frames
  • No laptop stickers
  • Don't display hardware wallets
  • Be careful with mail packaging (generic boxes preferred)

Don't Discuss​

  • Don't mention Bitcoin ownership to casual acquaintances
  • Be especially careful at Bitcoin events/meetups
  • Don't post on social media with real identity
  • "I don't own any" is a valid response

Don't Display​

  • Don't check portfolios in public
  • Don't have wallet apps on home screen
  • Be careful with screen visibility
  • Close Bitcoin tabs when others can see

Home Security Basics​

If you hold significant Bitcoin, basic home security matters:

Physical Barriers​

  • Quality locks on all entry points
  • Reinforced door frames (kicks break frames, not locks)
  • Window security — locks, film, or bars where appropriate
  • Lighting — motion-activated exterior lights
  • Visibility — trim bushes near windows/doors

Monitoring​

  • Cameras — Visible deterrent + evidence
  • Alarm system — Monitored service recommended
  • Smart locks — Know when doors open
  • Neighbors — Community awareness helps

Safe Storage​

For hardware wallets and backup materials:

  • Home safe — Fire-rated, bolted down
  • Hidden location — Not the master bedroom (first place checked)
  • Decoy valuables — Give burglars something to take
  • Off-site backup — Don't keep everything in one location

Seed Backup Storage​

Your seed backup is the most sensitive physical item.

Storage Options​

LocationProsCons
Home safeAccessible, you control itKnown location, fire/flood risk
Bank safe deposit boxSecure, fire-protectedBank access required, not truly private
Buried/hiddenVery hard to findForgetting location, environmental damage
Trusted familyGeographic distributionTrust required, their security matters
Multiple locationsRedundancyMore exposure points

Best Practices​

  • Metal backup — Paper burns; metal survives fires
  • Multiple copies — At least 2-3 in different locations
  • Geographic distribution — Different cities if possible
  • Tamper evidence — Know if backup has been accessed
  • Documentation — Record where backups are (securely)

What NOT to Do​

❌ Single backup in one location ❌ Paper-only backup ❌ Bank safe deposit box as only copy ❌ Unprotected in a drawer ❌ Hidden somewhere you might forget

Duress Protection​

If you're ever in a situation where you're being coerced:

Plausible Deniability​

Decoy wallet strategy:

  1. Primary wallet (large holdings) with passphrase
  2. Decoy wallet (small amount) without passphrase
  3. If coerced, reveal only the decoy

How it works:

  • Same seed phrase generates two different wallets
  • Without passphrase → Decoy wallet
  • With passphrase → Real wallet
  • Attacker can't know the passphrase wallet exists
Limitations

This only works if:

  • Attacker doesn't know about passphrases
  • Decoy has believable amount
  • You can convincingly act defeated
  • Attacker doesn't do research first

Multisig Distribution​

With multisig, you genuinely cannot access funds alone:

  • "I need my partners to sign"
  • "The other keys are in different locations"
  • This isn't a bluff—it's true

This makes you a less attractive target.

Time Locks​

Some setups allow time-delayed transactions:

  • Even if coerced, funds aren't immediately available
  • Provides time for intervention
  • More complex to set up

Travel Security​

Traveling with Bitcoin requires additional consideration.

General Principles​

  • Minimize what you carry — Only what you need
  • Don't advertise — No Bitcoin merchandise or visible hardware
  • Separate wallets — Travel wallet vs. main holdings
  • Know local laws — Cryptocurrency regulations vary

Hardware Wallet Travel​

Options:

  1. Don't bring it — Access via secure remote method if needed
  2. Bring empty device — Create new wallet at destination if needed
  3. Bring loaded device — Necessary for spending, increases risk

If bringing a device:

  • Keep in carry-on (never checked luggage)
  • Know how to explain it at security
  • Consider a small decoy amount
  • Memorize PIN (don't write it down)

Border Crossings​

  • Legal requirements vary — Some countries require declaring crypto
  • Device searches — Can you be compelled to unlock?
  • Plausible deniability — Empty device, passphrase wallet
  • Know your rights — Research before traveling

Accommodation​

  • Hotel safes — Better than nothing, not truly secure
  • Don't leave devices unattended — Maid service access
  • Be aware of surroundings — Who sees you with device?

Emergency Planning​

Have a plan for various scenarios:

If Your Home is Burglarized​

  1. Check if backup was accessed (tamper evidence)
  2. If compromised, move funds to new wallet immediately
  3. File police report (for insurance, not recovery expectation)
  4. Review security, upgrade where needed

If You're Physically Threatened​

  1. Comply if necessary — Bitcoin isn't worth injury or death
  2. Give access to decoy wallet if you have one
  3. Report to police when safe
  4. Move any remaining funds to new setup

If Backup is Stolen​

  1. Move funds immediately if you still have device access
  2. Create new wallet with new seed
  3. Secure new backup better
  4. Consider what else was compromised

If Hardware Wallet is Stolen​

  1. Don't panic — PIN + limited attempts provides time
  2. Use backup to restore to new device
  3. Move funds to new wallet (new seed)
  4. Old seed should be considered compromised

Security vs. Paranoia​

Balance is important:

Appropriate security:

  • Matches your actual threat level
  • Doesn't significantly impair your life
  • Is consistently maintainable
  • Allows you to still use your Bitcoin

Paranoia:

  • Excessive for your actual risk
  • Causes significant stress
  • Makes setup so complex you lock yourself out
  • Prevents you from ever actually using Bitcoin

Most people need:

  • Basic OpSec (don't advertise)
  • Hardware wallet
  • Distributed backups
  • Basic home security

Few people need:

  • Elaborate decoy systems
  • Underground bunkers
  • Professional security teams

Summary​

Physical security for Bitcoin:

  1. Prevention — Don't let attackers know you're a target
  2. Barriers — Basic home security, secure storage
  3. Distribution — Don't keep everything in one place
  4. Contingency — Decoy wallets, duress planning
  5. Balance — Match security to actual threat level

The goal is making yourself a harder target than alternatives, not achieving perfect security.