diff --git a/gitnexus-claude-plugin/hooks/gitnexus-hook.js b/gitnexus-claude-plugin/hooks/gitnexus-hook.js
index 5d0c722e1..577e7f16c 100644
--- a/gitnexus-claude-plugin/hooks/gitnexus-hook.js
+++ b/gitnexus-claude-plugin/hooks/gitnexus-hook.js
@@ -248,8 +248,15 @@ function acquireHookSlot(gitNexusDir) {
               try {
                 process.kill(owner, 0);
                 isLive = true;
-              } catch {
-                /* ESRCH (or EPERM under cross-user) — treat as dead */
+              } catch (e) {
+                // ESRCH = process gone → treat as dead. EPERM = process exists
+                // but owned by another user (cross-user lock dir) → still alive,
+                // keep the slot. Anything else: be conservative, assume alive.
+                if (e && e.code === 'ESRCH') {
+                  isLive = false;
+                } else {
+                  isLive = true;
+                }
               }
             }
           }
diff --git a/gitnexus-cursor-integration/hooks/gitnexus-hook.cjs b/gitnexus-cursor-integration/hooks/gitnexus-hook.cjs
index 245c5fcfc..d4c3035fb 100644
--- a/gitnexus-cursor-integration/hooks/gitnexus-hook.cjs
+++ b/gitnexus-cursor-integration/hooks/gitnexus-hook.cjs
@@ -278,8 +278,15 @@ function acquireHookSlot(gitNexusDir) {
               try {
                 process.kill(owner, 0);
                 isLive = true;
-              } catch {
-                /* ESRCH (or EPERM under cross-user) — treat as dead */
+              } catch (e) {
+                // ESRCH = process gone → treat as dead. EPERM = process exists
+                // but owned by another user (cross-user lock dir) → still alive,
+                // keep the slot. Anything else: be conservative, assume alive.
+                if (e && e.code === 'ESRCH') {
+                  isLive = false;
+                } else {
+                  isLive = true;
+                }
               }
             }
           }
diff --git a/gitnexus/hooks/claude/gitnexus-hook.cjs b/gitnexus/hooks/claude/gitnexus-hook.cjs
index 7db0e23e1..23baf9af1 100755
--- a/gitnexus/hooks/claude/gitnexus-hook.cjs
+++ b/gitnexus/hooks/claude/gitnexus-hook.cjs
@@ -248,8 +248,15 @@ function acquireHookSlot(gitNexusDir) {
               try {
                 process.kill(owner, 0);
                 isLive = true;
-              } catch {
-                /* ESRCH (or EPERM under cross-user) — treat as dead */
+              } catch (e) {
+                // ESRCH = process gone → treat as dead. EPERM = process exists
+                // but owned by another user (cross-user lock dir) → still alive,
+                // keep the slot. Anything else: be conservative, assume alive.
+                if (e && e.code === 'ESRCH') {
+                  isLive = false;
+                } else {
+                  isLive = true;
+                }
               }
             }
           }