diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5cbd71949a..de4f960e9b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,7 @@ An AssertJ style API for testing KtLint rules ([#1444](https://github.com/pinter
 - Add experimental rule for consistent spacing before the start of the function body (`function-start-of-body-spacing`) ([#1341](https://github.com/pinterest/ktlint/issues/1341))
 
 ### Fixed
+- Fix check of spacing in the receiver type of an anonymous function ([#1440](https://github.com/pinterest/ktlint/issues/1440))
 
 ### Changed
 * Set Kotlin development version to `1.6.21` and Kotlin version to `1.6.21`.
diff --git a/ktlint-ruleset-experimental/src/main/kotlin/com/pinterest/ktlint/ruleset/experimental/FunctionTypeReferenceSpacingRule.kt b/ktlint-ruleset-experimental/src/main/kotlin/com/pinterest/ktlint/ruleset/experimental/FunctionTypeReferenceSpacingRule.kt
index 4955b11fa8..ce7bacb00b 100644
--- a/ktlint-ruleset-experimental/src/main/kotlin/com/pinterest/ktlint/ruleset/experimental/FunctionTypeReferenceSpacingRule.kt
+++ b/ktlint-ruleset-experimental/src/main/kotlin/com/pinterest/ktlint/ruleset/experimental/FunctionTypeReferenceSpacingRule.kt
@@ -2,9 +2,9 @@ package com.pinterest.ktlint.ruleset.experimental
 
 import com.pinterest.ktlint.core.Rule
 import com.pinterest.ktlint.core.ast.ElementType.FUN
-import com.pinterest.ktlint.core.ast.ElementType.IDENTIFIER
 import com.pinterest.ktlint.core.ast.ElementType.NULLABLE_TYPE
 import com.pinterest.ktlint.core.ast.ElementType.TYPE_REFERENCE
+import com.pinterest.ktlint.core.ast.ElementType.VALUE_PARAMETER_LIST
 import com.pinterest.ktlint.core.ast.ElementType.WHITE_SPACE
 import com.pinterest.ktlint.core.ast.nextSibling
 import org.jetbrains.kotlin.com.intellij.lang.ASTNode
@@ -17,26 +17,26 @@ public class FunctionTypeReferenceSpacingRule : Rule("function-type-reference-sp
     ) {
         if (node.elementType == FUN) {
             node
-                .findTypeReferenceBeforeFunctionIdentifier()
+                .findFunctionReceiverTypeReference()
                 ?.let { typeReference ->
                     typeReference
                         .firstChildNode
                         .takeIf { it.elementType == NULLABLE_TYPE }
                         ?.let { nullableTypeElement ->
-                            visitNodesUntilIdentifier(nullableTypeElement.firstChildNode, emit, autoCorrect)
+                            visitNodesUntilStartOfValueParameterList(nullableTypeElement.firstChildNode, emit, autoCorrect)
                         }
 
                     if (typeReference.elementType != NULLABLE_TYPE) {
-                        visitNodesUntilIdentifier(typeReference, emit, autoCorrect)
+                        visitNodesUntilStartOfValueParameterList(typeReference, emit, autoCorrect)
                     }
                 }
         }
     }
 
-    private fun ASTNode.findTypeReferenceBeforeFunctionIdentifier(): ASTNode? {
+    private fun ASTNode.findFunctionReceiverTypeReference(): ASTNode? {
         require(elementType == FUN)
         var currentNode: ASTNode? = firstChildNode
-        while (currentNode != null && currentNode.elementType != IDENTIFIER) {
+        while (currentNode != null && currentNode.elementType != VALUE_PARAMETER_LIST) {
             if (currentNode.elementType == TYPE_REFERENCE) {
                 return currentNode
             }
@@ -45,13 +45,13 @@ public class FunctionTypeReferenceSpacingRule : Rule("function-type-reference-sp
         return null
     }
 
-    private fun visitNodesUntilIdentifier(
+    private fun visitNodesUntilStartOfValueParameterList(
         node: ASTNode,
         emit: (offset: Int, errorMessage: String, canBeAutoCorrected: Boolean) -> Unit,
         autoCorrect: Boolean
     ) {
         var currentNode: ASTNode? = node
-        while (currentNode != null && currentNode.elementType != IDENTIFIER) {
+        while (currentNode != null && currentNode.elementType != VALUE_PARAMETER_LIST) {
             val nextNode = currentNode.nextSibling { true }
             removeIfNonEmptyWhiteSpace(currentNode, emit, autoCorrect)
             currentNode = nextNode
diff --git a/ktlint-ruleset-experimental/src/test/kotlin/com/pinterest/ktlint/ruleset/experimental/FunctionTypeReferenceSpacingRuleTest.kt b/ktlint-ruleset-experimental/src/test/kotlin/com/pinterest/ktlint/ruleset/experimental/FunctionTypeReferenceSpacingRuleTest.kt
index fbcbe0e93d..bbc360827f 100644
--- a/ktlint-ruleset-experimental/src/test/kotlin/com/pinterest/ktlint/ruleset/experimental/FunctionTypeReferenceSpacingRuleTest.kt
+++ b/ktlint-ruleset-experimental/src/test/kotlin/com/pinterest/ktlint/ruleset/experimental/FunctionTypeReferenceSpacingRuleTest.kt
@@ -75,4 +75,40 @@ class FunctionTypeReferenceSpacingRuleTest {
             """.trimIndent()
         functionTypeReferenceSpacingRuleAssertThat(code).hasNoLintViolations()
     }
+
+    @Test
+    fun `Issue 1440 - Given an anonymous function without receiver type then do not reformat`() {
+        val code =
+            """
+            val anonymousFunction = fun(foo: Boolean): String? = if (foo) "Test string" else null
+            """.trimIndent()
+        functionTypeReferenceSpacingRuleAssertThat(code).hasNoLintViolations()
+    }
+
+    @Test
+    fun `Given an anonymous function with receiver type then do not reformat`() {
+        val code =
+            """
+            val anonymousFunction = fun Boolean.(): String? = if (this) "Test string" else null
+            """.trimIndent()
+        functionTypeReferenceSpacingRuleAssertThat(code).hasNoLintViolations()
+    }
+
+    @Test
+    fun `Given an anonymous function with receiver type followed by an unexpected space then do reformat`() {
+        val code =
+            """
+            val anonymousFunction = fun Boolean ? . (): String? = this?.let { "Test string" }
+            """.trimIndent()
+        val formattedCode =
+            """
+            val anonymousFunction = fun Boolean?.(): String? = this?.let { "Test string" }
+            """.trimIndent()
+        functionTypeReferenceSpacingRuleAssertThat(code)
+            .hasLintViolations(
+                LintViolation(1, 36, "Unexpected whitespace"),
+                LintViolation(1, 38, "Unexpected whitespace"),
+                LintViolation(1, 40, "Unexpected whitespace")
+            ).isFormattedAs(formattedCode)
+    }
 }