A transaction paid 1 bitcoin to a hundred addresses. None of them look like addresses. What was being bought?
On 30 July 2011, three weeks after cryptographer Len Sassaman died, Dan Kaminsky encoded an ASCII portrait into Bitcoin itself.
The appearance
One input of 1 BTC, a 0.15 BTC fee, and 100 outputs. Read as money, it is a messy split. Read as bytes, the 20-byte HASH160 fields of the outputs are not key hashes at all. They are ASCII. Lined up, they spell a 20-column tribute, complete with two faces drawn in punctuation.
Case file sealed
Investigation notes, the reconstruction, and sources sit behind this seal. Open it when you have sat with the raw transaction.
Open the case file
The investigation
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01 The encoding
A standard pay-to-public-key-hash output is OP_DUP OP_HASH160 <20 bytes> OP_EQUALVERIFY OP_CHECKSIG. Kaminsky left the opcodes alone and replaced the 20 bytes with text. The first data line is the ASCII for '---BEGIN TRIBUTE---'. Because HASH160 of a real public key is uniformly random, no private key will ever hash to that exact 20-byte string. The outputs are unspendable by construction.
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02 What it cost
He spent 0.15 BTC as a fee and locked about 0.76 BTC into the fake addresses — 0.01 BTC per line of the portrait. A small change output went to a real key. At $13.50 that week the memorial cost a few dollars. At 2026 prices the locked coins alone are tens of thousands of dollars, sitting in every full node as unspendable UTXOs.
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03 How to read it
Kaminsky told the wake at DNA Lounge, and later Black Hat USA 2011: run strings --bytes=20 on blk0001.dat (now blk00003) and the 78-line portrait appears. Bitcoin Talk reconstructed the transaction as 930a2114… in block 138,725. OP_RETURN did not exist yet. This is the document that taught the chain it could be a library.
Reconstruction
It is a funeral. Security researcher Dan Kaminsky used Bitcoin’s P2PKH template as a 20-character-wide typesetting engine, burning bitcoin into an ASCII portrait of Len Sassaman so that every full node would carry it forever. The 'addresses' were never meant to be spent. They are the picture.