diff --git a/rtl/ibex_core.sv b/rtl/ibex_core.sv
index 9ca9a8af..ddcf9df9 100644
--- a/rtl/ibex_core.sv
+++ b/rtl/ibex_core.sv
@@ -18,7 +18,7 @@ module ibex_core #(
     parameter int unsigned MHPMCounterWidth         = 40,
     parameter bit          RV32E                    = 1'b0,
     parameter bit          RV32M                    = 1'b1,
-    parameter string       MultiplierImplementation = "fast",
+    parameter              MultiplierImplementation = "fast",
     parameter int unsigned DmHaltAddr               = 32'h1A110800,
     parameter int unsigned DmExceptionAddr          = 32'h1A110808
 ) (
diff --git a/rtl/ibex_core_tracing.sv b/rtl/ibex_core_tracing.sv
index cc204d9d..3d4653b9 100644
--- a/rtl/ibex_core_tracing.sv
+++ b/rtl/ibex_core_tracing.sv
@@ -14,7 +14,7 @@ module ibex_core_tracing #(
     parameter int unsigned MHPMCounterWidth         = 40,
     parameter bit          RV32E                    = 1'b0,
     parameter bit          RV32M                    = 1'b1,
-    parameter string       MultiplierImplementation = "fast",
+    parameter              MultiplierImplementation = "fast",
     parameter int unsigned DmHaltAddr               = 32'h1A110800,
     parameter int unsigned DmExceptionAddr          = 32'h1A110808
 ) (
diff --git a/rtl/ibex_ex_block.sv b/rtl/ibex_ex_block.sv
index f2910bd3..71b4e9a2 100644
--- a/rtl/ibex_ex_block.sv
+++ b/rtl/ibex_ex_block.sv
@@ -10,7 +10,7 @@
  */
 module ibex_ex_block #(
     parameter bit    RV32M                    = 1,
-    parameter string MultiplierImplementation = "fast"
+    parameter        MultiplierImplementation = "fast"
 ) (
     input  logic              clk_i,
     input  logic              rst_ni,