diff --git a/src/ast/nodes/ArrayPattern.ts b/src/ast/nodes/ArrayPattern.ts
index 54dc76b5f26..daf57eb35ea 100644
--- a/src/ast/nodes/ArrayPattern.ts
+++ b/src/ast/nodes/ArrayPattern.ts
@@ -87,8 +87,21 @@ export default class ArrayPattern extends NodeBase implements DeclarationPattern
 		let included = false;
 		const includedPatternPath = getIncludedPatternPath(destructuredInitPath);
 		for (const element of this.elements) {
-			included =
-				element?.includeDestructuredIfNecessary(context, includedPatternPath, init) || included;
+			if (element) {
+				element.included ||= included;
+				included =
+					element.includeDestructuredIfNecessary(context, includedPatternPath, init) || included;
+			}
+		}
+		if (included) {
+			// This is necessary so that if any pattern element is included, all are
+			// included for proper deconflicting
+			for (const element of this.elements) {
+				if (element && !element.included) {
+					element.included = true;
+					element.includeDestructuredIfNecessary(context, includedPatternPath, init);
+				}
+			}
 		}
 		return (this.included ||= included);
 	}
diff --git a/src/ast/nodes/AssignmentPattern.ts b/src/ast/nodes/AssignmentPattern.ts
index fc32c7e5c63..e071fe980fe 100644
--- a/src/ast/nodes/AssignmentPattern.ts
+++ b/src/ast/nodes/AssignmentPattern.ts
@@ -70,6 +70,12 @@ export default class AssignmentPattern extends NodeBase implements DeclarationPa
 			this.included;
 		if ((included ||= this.right.shouldBeIncluded(context))) {
 			this.right.includePath(UNKNOWN_PATH, context, false);
+			if (!this.left.included) {
+				this.left.included = true;
+				// Unfortunately, we need to include the left side again now, so that
+				// any declared variables are properly included.
+				this.left.includeDestructuredIfNecessary(context, destructuredInitPath, init);
+			}
 		}
 		return (this.included = included);
 	}
diff --git a/src/ast/nodes/Property.ts b/src/ast/nodes/Property.ts
index 96c2579d3fa..b71f96a9be4 100644
--- a/src/ast/nodes/Property.ts
+++ b/src/ast/nodes/Property.ts
@@ -77,15 +77,18 @@ export default class Property extends MethodBase implements DeclarationPatternNo
 		destructuredInitPath: ObjectPath,
 		init: ExpressionEntity
 	): boolean {
+		const path = this.getPathInProperty(destructuredInitPath);
 		let included =
-			(this.value as PatternNode).includeDestructuredIfNecessary(
-				context,
-				this.getPathInProperty(destructuredInitPath),
-				init
-			) || this.included;
-		included ||= this.key.hasEffects(createHasEffectsContext());
-		if (included) {
+			(this.value as PatternNode).includeDestructuredIfNecessary(context, path, init) ||
+			this.included;
+		if ((included ||= this.key.hasEffects(createHasEffectsContext()))) {
 			this.key.includePath(EMPTY_PATH, context, false);
+			if (!this.value.included) {
+				this.value.included = true;
+				// Unfortunately, we need to include the value again now, so that any
+				// declared variables are properly included.
+				(this.value as PatternNode).includeDestructuredIfNecessary(context, path, init);
+			}
 		}
 		return (this.included = included);
 	}
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/_config.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/_config.js
new file mode 100644
index 00000000000..cdeea3d02ee
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'makes sure to deconflict all variables in an array pattern if included'
+});
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/dep.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/dep.js
new file mode 100644
index 00000000000..9bcefbb3169
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/dep.js
@@ -0,0 +1,2 @@
+const Foo = { ok: true };
+export { Foo as default };
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/main.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/main.js
new file mode 100644
index 00000000000..473a5dc8d3e
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-array-pattern/main.js
@@ -0,0 +1,6 @@
+import bar from './dep.js';
+
+const [Foo, Bar] = [1, 2];
+
+assert.deepStrictEqual(bar, { ok: true });
+assert.deepStrictEqual(Bar, 2);
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/_config.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/_config.js
new file mode 100644
index 00000000000..7778227903e
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/_config.js
@@ -0,0 +1,4 @@
+module.exports = defineTest({
+	description:
+		'makes sure to deconflict variables that are destructured for side effects in their array pattern default values only'
+});
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/dep.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/dep.js
new file mode 100644
index 00000000000..9bcefbb3169
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/dep.js
@@ -0,0 +1,2 @@
+const Foo = { ok: true };
+export { Foo as default };
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/main.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/main.js
new file mode 100644
index 00000000000..cbcf4a15b58
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects-array/main.js
@@ -0,0 +1,9 @@
+import bar from './dep.js';
+let mutated = false;
+const [
+	Foo = (() => {
+		mutated = true;
+	})()
+] = [];
+assert.ok(mutated);
+assert.deepStrictEqual(bar, { ok: true });
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/_config.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/_config.js
new file mode 100644
index 00000000000..df011c9a1ae
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/_config.js
@@ -0,0 +1,4 @@
+module.exports = defineTest({
+	description:
+		'makes sure to deconflict variables that are destructured for side effects in their default values only'
+});
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/dep.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/dep.js
new file mode 100644
index 00000000000..9bcefbb3169
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/dep.js
@@ -0,0 +1,2 @@
+const Foo = { ok: true };
+export { Foo as default };
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/main.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/main.js
new file mode 100644
index 00000000000..c39128e9fd5
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-default-side-effects/main.js
@@ -0,0 +1,9 @@
+import bar from './dep.js';
+let mutated = false;
+const {
+	Foo = (() => {
+		mutated = true;
+	})()
+} = {};
+assert.ok(mutated);
+assert.deepStrictEqual(bar, { ok: true });
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/_config.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/_config.js
new file mode 100644
index 00000000000..c7e939766f5
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/_config.js
@@ -0,0 +1,4 @@
+module.exports = defineTest({
+	description:
+		'makes sure to deconflict variables that are destructured for side effects in their key only'
+});
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/dep.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/dep.js
new file mode 100644
index 00000000000..9bcefbb3169
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/dep.js
@@ -0,0 +1,2 @@
+const Foo = { ok: true };
+export { Foo as default };
diff --git a/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/main.js b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/main.js
new file mode 100644
index 00000000000..2809a2f9e93
--- /dev/null
+++ b/test/function/samples/object-expression-treeshaking/deconflict-destructured-for-key-side-effects/main.js
@@ -0,0 +1,10 @@
+import bar from './dep.js';
+let mutated = false;
+const {
+	[(() => {
+		mutated = true;
+		return 'Foo';
+	})()]: Foo
+} = { Foo: true };
+assert.ok(mutated);
+assert.deepStrictEqual(bar, { ok: true });