diff --git a/src/include/ngspice/devdefs.h b/src/include/ngspice/devdefs.h
index ea0817b1a..3d7955935 100644
--- a/src/include/ngspice/devdefs.h
+++ b/src/include/ngspice/devdefs.h
@@ -142,6 +142,7 @@ extern int        DEVmaxnum;    /* size of DEVices array */
 
 # define IOP(a,b,c,d)   { a, b, c|IF_SET|IF_ASK,			d }
 # define IOPU(a,b,c,d)   { a, b, c|IF_SET|IF_ASK|IF_UNINTERESTING,	d }
+# define IOPUR(a,b,c,d)  { a, b, c|IF_SET|IF_ASK|IF_UNINTERESTING|IF_REDUNDANT, d }
 # define IOPP(a,b,c,d)  { a, b, c|IF_SET|IF_ASK|IF_PRINCIPAL,		d }
 # define IOPA(a,b,c,d)  { a, b, c|IF_SET|IF_ASK|IF_AC,			d }
 # define IOPAR(a,b,c,d)  { a, b, c|IF_SET|IF_ASK|IF_AC|IF_REDUNDANT,    d }
diff --git a/src/spicelib/devices/dio/dio.c b/src/spicelib/devices/dio/dio.c
index d55a38fbb..fc869995c 100644
--- a/src/spicelib/devices/dio/dio.c
+++ b/src/spicelib/devices/dio/dio.c
@@ -45,7 +45,7 @@ IFparm DIOmPTable[] = { /* model parameters */
  IOP( "jsw", DIO_MOD_JSW,  IF_REAL, "Sidewall Saturation current"),
 
  IOPU( "tnom",DIO_MOD_TNOM,IF_REAL, "Parameter measurement temperature"),
- IOPR( "tref",DIO_MOD_TNOM,IF_REAL, "Parameter measurement temperature"),
+ IOPUR("tref",DIO_MOD_TNOM,IF_REAL, "Parameter measurement temperature"),
  IOP( "rs",  DIO_MOD_RS,  IF_REAL, "Ohmic resistance"),
  IOP( "trs", DIO_MOD_TRS, IF_REAL, "Ohmic resistance 1st order temp. coeff."),
  IOPR( "trs1", DIO_MOD_TRS, IF_REAL, "Ohmic resistance 1st order temp. coeff."),
diff --git a/src/spicelib/devices/mos3/mos3.c b/src/spicelib/devices/mos3/mos3.c
index b132316d2..22e0ac2ab 100644
--- a/src/spicelib/devices/mos3/mos3.c
+++ b/src/spicelib/devices/mos3/mos3.c
@@ -137,7 +137,7 @@ IFparm MOS3mPTable[] = { /* model parameters */
  IOP("wd",    MOS3_MOD_WD,    IF_REAL   ,"Width Narrowing (Diffusion)"),
  IOP("xw",    MOS3_MOD_XW,    IF_REAL   ,"Width mask adjustment"),
  IOPU("delvto",   MOS3_MOD_DELVTO,   IF_REAL   ,"Threshold voltage Adjust"),
- IOPR("delvt0",   MOS3_MOD_DELVTO,   IF_REAL   ,"Threshold voltage Adjust"),
+ IOPUR("delvt0",  MOS3_MOD_DELVTO,   IF_REAL   ,"Threshold voltage Adjust"),
  IOP("u0",    MOS3_MOD_U0,    IF_REAL   ,"Surface mobility"),
  IOPR("uo",    MOS3_MOD_U0,    IF_REAL   ,"Surface mobility"),
  IOP("fc",    MOS3_MOD_FC,    IF_REAL   ,"Forward bias jct. fit parm."),
diff --git a/src/spicelib/devices/mos9/mos9.c b/src/spicelib/devices/mos9/mos9.c
index 85447c08f..c901b48b6 100644
--- a/src/spicelib/devices/mos9/mos9.c
+++ b/src/spicelib/devices/mos9/mos9.c
@@ -138,7 +138,7 @@ IFparm MOS9mPTable[] = { /* model parameters */
  IOP("wd",    MOS9_MOD_WD,    IF_REAL   ,"Width Narrowing (Diffusion)"),
  IOP("xw",    MOS9_MOD_XW,    IF_REAL   ,"Width mask adjustment"),
  IOPU("delvto",   MOS9_MOD_DELVTO,   IF_REAL   ,"Threshold voltage Adjust"),
- IOPR("delvt0",   MOS9_MOD_DELVTO,   IF_REAL   ,"Threshold voltage Adjust"),
+ IOPUR("delvt0",  MOS9_MOD_DELVTO,   IF_REAL   ,"Threshold voltage Adjust"),
  IOP("u0",    MOS9_MOD_U0,    IF_REAL   ,"Surface mobility"),
  IOPR("uo",    MOS9_MOD_U0,    IF_REAL   ,"Surface mobility"),
  IOP("fc",    MOS9_MOD_FC,    IF_REAL   ,"Forward bias jct. fit parm."),
diff --git a/src/spicelib/devices/res/res.c b/src/spicelib/devices/res/res.c
index 84fa5341a..edcb46b20 100644
--- a/src/spicelib/devices/res/res.c
+++ b/src/spicelib/devices/res/res.c
@@ -21,7 +21,7 @@ IFparm RESpTable[] = { /* parameters */
     IOPZU( "w",		RES_WIDTH,	     IF_REAL,    "Width"),
     IOPU(  "m",		RES_M,		     IF_REAL,    "Multiplication factor"),
     IOPU(  "tc",		RES_TC1,	     IF_REAL,    "First order temp. coefficient"),
-    IOPU(  "tc1",		RES_TC1,	     IF_REAL,    "First order temp. coefficient"),
+    IOPUR( "tc1",		RES_TC1,	     IF_REAL,    "First order temp. coefficient"),
     IOPU(  "tc2",		RES_TC2,	     IF_REAL,    "Second order temp. coefficient"),
     IOPU(  "tce",		RES_TCE,	     IF_REAL,    "exponential temp. coefficient"),
     IOP(   "bv_max",	RES_BV_MAX,	     IF_REAL,    "maximum voltage over resistor"),
diff --git a/src/spicelib/devices/tra/tra.c b/src/spicelib/devices/tra/tra.c
index fe0cc5188..ba1e0bdd6 100644
--- a/src/spicelib/devices/tra/tra.c
+++ b/src/spicelib/devices/tra/tra.c
@@ -11,7 +11,7 @@ Author: 1987 Thomas L. Quarles
 
 IFparm TRApTable[] = { /* parameters */ 
  IOPU( "z0", TRA_Z0,   IF_REAL   , "Characteristic impedance"),
- IOPR( "zo", TRA_Z0,   IF_REAL   , "Characteristic impedance"),
+ IOPUR( "zo", TRA_Z0,  IF_REAL   , "Characteristic impedance"),
  IOPAU( "f",  TRA_FREQ, IF_REAL   , "Frequency"),
  IOPAU( "td", TRA_TD,   IF_REAL   , "Transmission delay"),
  IOPAU( "nl", TRA_NL,   IF_REAL   , "Normalized length at frequency given"),