diff --git a/refclock_phc.c b/refclock_phc.c
index e0e206e..3b68c84 100644
--- a/refclock_phc.c
+++ b/refclock_phc.c
@@ -33,6 +33,9 @@
 
 #include "sysincl.h"
 
+#include <sys/sysmacros.h>
+
+#include "array.h"
 #include "refclock.h"
 #include "hwclock.h"
 #include "local.h"
@@ -44,14 +47,19 @@
 
 struct phc_instance {
   int fd;
+  int dev_index;
   int mode;
   int nocrossts;
   int extpps;
   int pin;
   int channel;
+  struct timespec last_extts;
   HCL_Instance clock;
 };
 
+/* Array of RCL_Instance with enabled extpps */
+static ARR_Instance extts_phcs = NULL;
+
 static void read_ext_pulse(int sockfd, int event, void *anything);
 
 static int phc_initialise(RCL_Instance instance)
@@ -59,6 +67,7 @@ static int phc_initialise(RCL_Instance instance)
   const char *options[] = {"nocrossts", "extpps", "pin", "channel", "clear", NULL};
   struct phc_instance *phc;
   int phc_fd, rising_edge;
+  struct stat st;
   char *path, *s;
 
   RCL_CheckDriverOptions(instance, options);
@@ -71,10 +80,13 @@ static int phc_initialise(RCL_Instance instance)
 
   phc = MallocNew(struct phc_instance);
   phc->fd = phc_fd;
+  if (fstat(phc_fd, &st) < 0 || !S_ISCHR(st.st_mode))
+    LOG_FATAL("Could not get PHC index");
+  phc->dev_index = minor(st.st_rdev);
   phc->mode = 0;
   phc->nocrossts = RCL_GetDriverOption(instance, "nocrossts") ? 1 : 0;
   phc->extpps = RCL_GetDriverOption(instance, "extpps") ? 1 : 0;
-
+  UTI_ZeroTimespec(&phc->last_extts);
   phc->clock = HCL_CreateInstance(0, 16, UTI_Log2ToDouble(RCL_GetDriverPoll(instance)),
                                   RCL_GetPrecision(instance));
 
@@ -90,6 +102,10 @@ static int phc_initialise(RCL_Instance instance)
       LOG_FATAL("Could not enable external PHC timestamping");
 
     SCH_AddFileHandler(phc->fd, SCH_FILE_INPUT, read_ext_pulse, instance);
+
+    if (!extts_phcs)
+      extts_phcs = ARR_CreateInstance(sizeof (RCL_Instance));
+    ARR_AppendElement(extts_phcs, &instance);
   } else {
     phc->pin = phc->channel = 0;
   }
@@ -101,12 +117,22 @@ static int phc_initialise(RCL_Instance instance)
 static void phc_finalise(RCL_Instance instance)
 {
   struct phc_instance *phc;
+  unsigned int i;
 
   phc = (struct phc_instance *)RCL_GetDriverData(instance);
 
   if (phc->extpps) {
     SCH_RemoveFileHandler(phc->fd);
     SYS_Linux_SetPHCExtTimestamping(phc->fd, phc->pin, phc->channel, 0, 0, 0);
+
+    for (i = 0; i < ARR_GetSize(extts_phcs); i++) {
+      if ((*(RCL_Instance *)ARR_GetElement(extts_phcs, i)) == instance)
+        ARR_RemoveElement(extts_phcs, i--);
+    }
+    if (ARR_GetSize(extts_phcs) == 0) {
+      ARR_DestroyInstance(extts_phcs);
+      extts_phcs = NULL;
+    }
   }
 
   HCL_DestroyInstance(phc->clock);
@@ -114,30 +140,52 @@ static void phc_finalise(RCL_Instance instance)
   Free(phc);
 }
 
-static void read_ext_pulse(int fd, int event, void *anything)
+static void process_ext_pulse(RCL_Instance instance, struct timespec *phc_ts)
 {
-  RCL_Instance instance;
   struct phc_instance *phc;
-  struct timespec phc_ts, local_ts;
+  struct timespec local_ts;
   double local_err;
-  int channel;
 
-  instance = anything;
   phc = RCL_GetDriverData(instance);
 
-  if (!SYS_Linux_ReadPHCExtTimestamp(phc->fd, &phc_ts, &channel))
-    return;
-
-  if (channel != phc->channel) {
-    DEBUG_LOG("Unexpected extts channel %d\n", channel);
+  if (UTI_CompareTimespecs(&phc->last_extts, phc_ts) == 0) {
+    DEBUG_LOG("Ignoring duplicated PHC timestamp");
     return;
   }
+  phc->last_extts = *phc_ts;
 
-  if (!HCL_CookTime(phc->clock, &phc_ts, &local_ts, &local_err))
+  if (!HCL_CookTime(phc->clock, phc_ts, &local_ts, &local_err))
     return;
 
   RCL_AddCookedPulse(instance, &local_ts, 1.0e-9 * local_ts.tv_nsec, local_err,
-                     UTI_DiffTimespecsToDouble(&phc_ts, &local_ts));
+                     UTI_DiffTimespecsToDouble(phc_ts, &local_ts));
+}
+
+static void read_ext_pulse(int fd, int event, void *anything)
+{
+  RCL_Instance instance;
+  struct phc_instance *phc1, *phc2;
+  struct timespec phc_ts;
+  unsigned int i;
+  int channel;
+
+  if (!SYS_Linux_ReadPHCExtTimestamp(fd, &phc_ts, &channel))
+    return;
+
+  instance = anything;
+  phc1 = RCL_GetDriverData(instance);
+
+  /* The Linux kernel (as of 6.2) has one shared queue of timestamps for all
+     descriptors of the same PHC.  Search for all refclocks that expect
+     the timestamp. */
+
+  for (i = 0; i < ARR_GetSize(extts_phcs); i++) {
+    instance = *(RCL_Instance *)ARR_GetElement(extts_phcs, i);
+    phc2 = RCL_GetDriverData(instance);
+    if (!phc2->extpps || phc2->dev_index != phc1->dev_index || phc2->channel != channel)
+      continue;
+    process_ext_pulse(instance, &phc_ts);
+  }
 }
 
 #define PHC_READINGS 25