Bitcoin is not anonymous contrary to popular belief. However many agree that privacy is a fundamental human right that everyone needs. Blockchain analysis has become a billion dollar industry with blockchain forensic services charging top dollar for their analysis to law enforcement governments, banking cartels, militaries, intelligence agencies, tax collectors and major Bitcoin exchanges worldwide. How can we spread financial freedom and privacy in the name of a truly free market?

If a single address from your Wallet is known and linked to you, statistically 70% of your wallets addresses can also be tracked as this privacy paper explains. Several open source Bitcoin wallets like Samourai and Wasabi have begun incorporating privacy features which will destroy the basic assumptions this kind of chain analysis is based on.

Cash money is a good example of fungible money (for example a $10 note), usually you don't know or care where it came from. It is accepted by everyone, whether at the gas station, in the red light district or in the supermarket. There are of course exceptions so a bank robber that stole many numbered bank notes might have problems with the fungibility aspect, but in normal life no one reads bank note numbers and will accept a note as long as it doesn't look forged. Plus there is the money washer argument, of course, but the biggest money washers are systemically important banks and they make that quite legal.

Here are some recommendations for anonymity in crypto:

  • Use cash to get in and out of Crypto.
    While this is not a very user friendly option, if privacy is important to you this might be the best tip of them all: Simply never ever use any service that requires AML/KYC. This is how law enforcement ties your real name to your Bitcoin address, exchanges are more than happy to cooperate. A good alternative for buying and selling Bitcoin without AML/KYC is Bisq.
  • Use an VPN (virtual private network) for anonymity
    Always connect to the internet through a network like privacy optimized version of Firefox, or the Tor browser. There are others like I2P, Bitmessage, Zeronet, and Freenet that are engineered towards privacy security and anonymity, although at varying degrees of accessibility to the non-technologically inclined.
    This won't change anything about your bitcoin transactions, but in general you will be much harder to trace if you are behind a VPN or routed through the Tor network, e.g. if you want to chat, trade or interact anonymously on the internet.
  • Never reuse Bitcoin addresses
    Re-using a Bitcoin address is a massive privacy and security risk. It makes it easier for blockchain analysis agencies to use heuristics to de-anonymize you, as well as others who may have transacted with you. Reusing addresses is the virtual version of spreading an STD. The best practice is to use a new Bitcoin address for every single payment you receive, and never send money twice to the same exact Bitcoin address.

Luckily many of the newer wallets are Hierarchical Deterministic (HD Wallets), which means that you can generate an unlimited number of public addresses from a single seed, as well as recover the wallet completely, from the very same seed. Most newer wallets are still SPV wallets, however, and are vulnerable to a wide variety of security vulnerabilities.

You can use Wasabi on laptops, Samourai on phones, Electrum for BTCPay
server, and a Cold Card or Hardware Wallets as offline cold storage solutions. Cold Card and Electrum allow you to sign transactions offline, for added privacy and security.

Signing transactions offline also opens the door to utilizing a Bitcoin satellite node and the Gotenna mesh network, for next level privacy.

Never use a wallet that uses Bloom Filters (BIP 37)
Bloom filters are defined as: A filter used primarily by SPV clients to request only matching transactions and blocks from full nodes.

Ok, now that we have established that, why does it matter if you use an SPV
wallet that utilizes Bloom Filters? Bloom filters were introduced for security,
right? Yes, but the implementation has lots of systemic flaws.

Without getting too technical and boring you to tears, I will refer to the Breaking
Bitcoin SPV security PDF
. In this document it states that an attacker could
possibly:
• spoof full-nodes
• block SPV requests
• spoof SPV requests

Our foes will use the tired but common excuses of drug trafficking, money laundering and terror financing as the age-old boogeyman to scare you into submission allowing them to strip you of your privacy and freedom, but we know better. This all means no personal freedom and total financial surveillance for everyone, while terrorists and criminals operate with impunity regardless. This conclusion does not even consider the higher costs of these financial services for customers who manage to jump through all the hoops of providing an intrusive level of personal information in order to be approved.

Conclusion

In the last few years, many people have realized that Bitcoin is not anonymous, and some of them have realized it with dire, life-destroying consequences. Bitcoin is pseudonymous and some have learned this lesson on the bitter end of a long prison sentence. The Bitcoin blockchain - while remarkable and revolutionary - is at it’s core, an immutable public ledger.

This means that every single transaction is unchangeably recorded and verifiable by every other participant in the network as long as electricity and the internet exist. This is not an optimal state of affairs for those who require privacy.

We hope these tips help, most people won't care as we can clearly see by the tiny amount of privacy transaction even in coins that have privacy options (or the use of Tor browsers, etc.), but at least be aware of whats possible and how things work.