diff --git a/test/fixtures/process/finalization-cleanup.mjs b/test/fixtures/process/finalization-cleanup.mjs
index 88d6c17cc7e3..8b7705b64d61 100644
--- a/test/fixtures/process/finalization-cleanup.mjs
+++ b/test/fixtures/process/finalization-cleanup.mjs
@@ -30,5 +30,7 @@ for (let i = 0; i < 10; i++) {
 }
 
 process.on('exit', function () {
+  // Keep `first` and `third` alive until exit; registrations only hold them weakly.
+  deepStrictEqual(keptAlive.map((obj) => obj.name), ['first', 'third'])
   deepStrictEqual(finalized, ['first', 'third'])
 })
diff --git a/test/fixtures/process/unregister-function.mjs b/test/fixtures/process/unregister-function.mjs
index b74a5b8203a0..01f704e4fa15 100644
--- a/test/fixtures/process/unregister-function.mjs
+++ b/test/fixtures/process/unregister-function.mjs
@@ -25,5 +25,8 @@ unregisterABeforeExit()
 unregisterBAgain()
 
 process.on('exit', function () {
+  // Keep `a` and `b` alive until exit; registrations only hold them weakly.
+  strictEqual(a.name, 'a')
+  strictEqual(b.name, 'b')
   strictEqual(calls.join(','), 'b:exit')
 })