# What are spent sats?

The sat ranges of already-spent outputs, which blockspace.to's ord fork keeps.

URL: https://blockspace.wiki/answers/what-are-spent-sats/

Here, [spent sats](https://blockspace.wiki/glossary/spent-sats/) means the sat ranges of outputs that have already been spent. blockspace.to, a Blockspace Labs product, runs a fork of ord with --index-spent-sats, so a spent output still answers with its sat ranges; an ord without that flag cannot. BTI's August 2026 handoff notes name CAT-21 as the only normal-operation consumer of those ranges.

Sources:

- The blockspacelabs.com page (index.html) · https://blockspacelabs.com
- Blockspace Holdings records
- The project list at block.space/projects · https://block.space/projects

Updated: 2026-10-20