diff --git a/proposals/1597-id-grammar.md b/proposals/1597-id-grammar.md
index bee1e71873b..102f652cb41 100644
--- a/proposals/1597-id-grammar.md
+++ b/proposals/1597-id-grammar.md
@@ -77,7 +77,7 @@ Proposal:
 > v1 rooms should be more tolerant.
 
 
-## Key IDs (for federation and e2e)
+## Key IDs (for federation, e2e, and identity servers)
 
 These are always of the form `<algorithm>:<tok>`.