Blockchains are transparent ledgers that everyone can read

Unlike traditional finance, most blockchains are public. This creates opportunities for investigators.

What blockchains show

• **Transactions**: Every transaction is recorded publicly.
• **Wallet addresses**: Public keys that receive and send funds.
• **Transaction amounts**: How much moved between addresses.
• **Timestamps**: When transactions occurred.
• **Transaction links**: Inputs and outputs connecting addresses.

What blockchains do not show

• **Real identities**: Addresses are pseudonymous.
• **Complete transaction purpose**: The blockchain does not explain why.
• **Off-chain activity**: What happened before funds hit the blockchain.

Key concept: Pseudonymity

Addresses are not names, but they can be connected to identities through:

• Exchange records (KYC required).
• Direct transactions to identified entities.
• Address reuse patterns.
• IP addresses if transaction broadcast was not anonymized.

Major blockchains

• **Bitcoin**: Oldest, most analyzed, most recognized.
• **Ethereum**: Smart contracts add complexity.
• **Stablecoins**: USDT, USDC pegged to fiat.
• **Layer 2 networks**: Faster but adds complexity.

Tools

• **Block explorers**: Blockchain.com, Etherscan, etc.
• **Chain analysis platforms**: Chainalysis, Elliptic for advanced work.
• **Clustering tools**: Identify when multiple addresses belong to same entity.