# Omni

The Mastercoin-lineage ledger, TetherUS included. BTI decodes Class C messages in OP_RETURN itself; a ledger token's bytes are its operations.

URL: https://blockspace.wiki/protocols/omni/

An [Omni property](https://blockspace.wiki/glossary/omni-property/) is a token of the Omni protocol, of the Mastercoin lineage. BTI's token table names it by its property id, assigned by replaying the protocol. A human name is an alias: TetherUS is property 31, and BTI writes it as `omni/31`.

## How Omni puts data on Bitcoin

The data-types reference lists three Omni channels over time:

- **Class A** (named in the reference as Mastercoin Class A): data in fake pay-to-pubkey-hash addresses, 20 bytes per output, with 546 sats of dust each. The reference calls the general trick undetectable by construction.
- **Class B**: data in fake public keys inside bare multisig outputs, which stay in the UTXO set until spent.
- **Class C**: a message in an OP_RETURN output.

Case 17 of the BTI case studies decodes a Class C simple send at block 560,000. The OP_RETURN output is 31 bytes, its script 22 bytes, beginning with the marker `6f6d6e69` ("omni"). The payload reads version 0, type 0 (simple send), property 31 (TetherUS), and an amount of 738,052,430,000 base units. A second, 546-sat output is the reference output: the recipient.

## How BTI attributes the bytes

Omni is a [native protocol](https://blockspace.wiki/glossary/native-protocol/): BTI's own decoder reads the chain, and there is no external indexer. The decoder reads **Class C only**. The adapters table says that is 99.67 % of Omni's bytes. Ruleset v1 names Class B as a coverage gap (B4b). omni-core is on the watchlist; deploying it would move Omni from native toward reconciled.

Omni carries no file. The books document gives it as the pure-ledger shape: "content 0 honestly; structure and overhead carry the backing — a ledger token's bytes are its operations".

The case studies show both sides of the dedication test:

- **Dedicated** (case 17, block 560,000). Every output serves the send or is change, so the claim covers the whole 257-byte transaction: content 0, structure 257, overhead 0, and the whole 50,000-sat fee. The case reconciled with the live database to the byte.
- **All riding** (case 21, block 550,000). A TetherUS send in a transaction that also paid 48,625 sats that no Omni rule required. The [dedicated](https://blockspace.wiki/glossary/dedicated/) test answers no, so the claim keeps only its frame, the reference output and its carrier: 75 bytes. With no dedicated claimant, the other 328 bytes "stay with the transaction", bought by nobody. In the ruleset's words, "every claimant aboard was a passenger".

## Live figures

The family's books (as of block 972,299, 2026-10-20 09:30:48 UTC):

| measure | value |
|---|---|
| Book A | 6.66 GB |
| share of the chain's bytes (Book A) | 0.86 % |
| share of all Book A bytes | 4.98 % |
| properties | 404 |
| operations | 19,432,030 |
| first height | [not measured](https://blockspace.wiki/glossary/not-measured/) |
| last height | 971614 |

The protocols API gives no first height for Omni, so this page says not measured rather than zero.

On 2026-10-18 the [heaviest tokens board](https://blockspace.wiki/glossary/heaviest-tokens-board/) placed `omni/31` third of all tokens by Book A, at 6.5 GB. It showed unnamed: the board had no label for it.

## Holders

The leaderboard cannot place Omni's bytes on addresses. Read on 2026-10-20, its coverage table listed Omni as not measured, because Blockspace Holdings keeps no Omni ledger.

## Measured findings

- In the July 2026 measurement run, Omni had a bytes:vbytes ratio of 1.0142, "pre-segwit, as expected": almost no [witness discount](https://blockspace.wiki/glossary/witness-discount/). Inscriptions measured 3.374 and runestones 1.0000.
- The same run lists Omni, with Counterparty and early OP_RETURN, as what was on the chain at height 600,000, when data payload was 9.2 % of block bytes.

Sources:

- Blockspace Holdings records
- block.space docs: data types · https://block.space/docs/datatypes
- block.space docs: measurements · https://block.space/docs/measurements
- block.space protocols API · https://block.space/api/protocols
- block.space leaderboard coverage API (holders measured per protocol) · https://block.space/api/leaderboard/coverage

Live figures: protocols as of block 972,299, 2026-10-20 09:30:48 UTC

Updated: 2026-10-20