diff --git a/CRAMv3.tex b/CRAMv3.tex
index c54abd35..92eec896 100644
--- a/CRAMv3.tex
+++ b/CRAMv3.tex
@@ -1325,7 +1325,7 @@ \subsubsection*{\textbf{Decode pseudocode}}
 \State \Call{DecodeTagData}{}\Comment{See section \ref{subsec:tags}}
 \Statex
 
-\If{$(BF$ AND $4) \ne 0$}\Comment{Unmapped flag}
+\If{$(BF$ AND $4) = 0$}\Comment{Unmapped flag}
   \State \Call{DecodeMappedRead}{}\Comment{See section \ref{subsec:mapped}}
 \Else
   \State \Call{DecodeUnmappedRead}{}\Comment{See section \ref{subsec:unmapped}}