diff --git a/kernel/celltypes.h b/kernel/celltypes.h
index 0da78c313..f8c73ed83 100644
--- a/kernel/celltypes.h
+++ b/kernel/celltypes.h
@@ -85,6 +85,7 @@ struct CellTypes
 		setup_internals_eval();
 
 		IdString A = "\\A", B = "\\B", EN = "\\EN", Y = "\\Y";
+		IdString SRC = "\\SRC", DST = "\\DST", DAT = "\\DAT";
 
 		setup_type("$tribuf", {A, EN}, {Y}, true);
 
@@ -99,6 +100,8 @@ struct CellTypes
 		setup_type("$allconst", pool<RTLIL::IdString>(), {Y}, true);
 		setup_type("$allseq", pool<RTLIL::IdString>(), {Y}, true);
 		setup_type("$equiv", {A, B}, {Y}, true);
+		setup_type("$specify2", {EN, SRC, DST}, pool<RTLIL::IdString>(), true);
+		setup_type("$specify3", {EN, SRC, DST, DAT}, pool<RTLIL::IdString>(), true);
 	}
 
 	void setup_internals_eval()
diff --git a/manual/CHAPTER_CellLib.tex b/manual/CHAPTER_CellLib.tex
index e64919182..96a309552 100644
--- a/manual/CHAPTER_CellLib.tex
+++ b/manual/CHAPTER_CellLib.tex
@@ -465,6 +465,10 @@ Add information about {\tt \$assert}, {\tt \$assume}, {\tt \$live}, {\tt \$fair}
 {\tt \$initstate}, {\tt \$anyconst}, {\tt \$anyseq}, {\tt \$allconst}, {\tt \$allseq} cells.
 \end{fixme}
 
+\begin{fixme}
+Add information about {\tt \$specify2} and {\tt \$specify3} cells.
+\end{fixme}
+
 \begin{fixme}
 Add information about {\tt \$slice} and {\tt \$concat} cells.
 \end{fixme}