diff --git a/src/Type/Regex/RegexExpressionHelper.php b/src/Type/Regex/RegexExpressionHelper.php
index 2b94fda6e2..0334aead77 100644
--- a/src/Type/Regex/RegexExpressionHelper.php
+++ b/src/Type/Regex/RegexExpressionHelper.php
@@ -11,6 +11,7 @@
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
 use function array_key_exists;
+use function ltrim;
 use function strrpos;
 use function substr;
 
@@ -147,6 +148,8 @@ public function getPatternDelimiters(Concat $concat, Scope $scope): array
 
 	private function getPatternDelimiter(string $regex): ?string
 	{
+		$regex = ltrim($regex);
+
 		if ($regex === '') {
 			return null;
 		}
diff --git a/src/Type/Regex/RegexGroupParser.php b/src/Type/Regex/RegexGroupParser.php
index 6938ff8000..8f282899ed 100644
--- a/src/Type/Regex/RegexGroupParser.php
+++ b/src/Type/Regex/RegexGroupParser.php
@@ -20,6 +20,7 @@
 use PHPStan\Type\StringType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
+use function array_merge;
 use function count;
 use function in_array;
 use function is_int;
@@ -432,7 +433,7 @@ private function walkGroupAst(
 					$isNonEmpty = TrinaryLogic::createYes();
 				}
 			}
-		} elseif (!in_array($ast->getId(), ['#capturing', '#namedcapturing'], true)) {
+		} elseif (!in_array($ast->getId(), ['#capturing', '#namedcapturing', '#alternation'], true)) {
 			$onlyLiterals = null;
 		}
 
@@ -447,6 +448,7 @@ private function walkGroupAst(
 			$isNumeric = TrinaryLogic::createNo();
 		}
 
+		$alternativeLiterals = [];
 		foreach ($children as $child) {
 			$this->walkGroupAst(
 				$child,
@@ -459,7 +461,24 @@ private function walkGroupAst(
 				$inClass,
 				$patternModifiers,
 			);
+
+			if ($ast->getId() !== '#alternation') {
+				continue;
+			}
+
+			if ($onlyLiterals !== null && $alternativeLiterals !== null) {
+				$alternativeLiterals = array_merge($alternativeLiterals, $onlyLiterals);
+				$onlyLiterals = [];
+			} else {
+				$alternativeLiterals = null;
+			}
 		}
+
+		if ($alternativeLiterals === null || $alternativeLiterals === []) {
+			return;
+		}
+
+		$onlyLiterals = $alternativeLiterals;
 	}
 
 	private function isMaybeEmptyNode(TreeNode $node, string $patternModifiers, bool &$isNonFalsy): bool
diff --git a/tests/PHPStan/Analyser/nsrt/bug-11311-php72.php b/tests/PHPStan/Analyser/nsrt/bug-11311-php72.php
index 40e6d99d9f..957b3557de 100644
--- a/tests/PHPStan/Analyser/nsrt/bug-11311-php72.php
+++ b/tests/PHPStan/Analyser/nsrt/bug-11311-php72.php
@@ -22,9 +22,9 @@ function doUnmatchedAsNull(string $s): void {
 // see https://3v4l.org/VeDob#veol
 function unmatchedAsNullWithOptionalGroup(string $s): void {
 	if (preg_match('/Price: (£|€)?\d+/', $s, $matches, PREG_UNMATCHED_AS_NULL)) {
-		assertType("array{0: string, 1?: non-empty-string}", $matches);
+		assertType("array{0: string, 1?: '£'|'€'}", $matches);
 	} else {
 		assertType('array{}', $matches);
 	}
-	assertType("array{}|array{0: string, 1?: non-empty-string}", $matches);
+	assertType("array{}|array{0: string, 1?: '£'|'€'}", $matches);
 }
diff --git a/tests/PHPStan/Analyser/nsrt/bug-11311.php b/tests/PHPStan/Analyser/nsrt/bug-11311.php
index 3a01594ded..0d2eaec66d 100644
--- a/tests/PHPStan/Analyser/nsrt/bug-11311.php
+++ b/tests/PHPStan/Analyser/nsrt/bug-11311.php
@@ -23,11 +23,11 @@ function doUnmatchedAsNull(string $s): void {
 function unmatchedAsNullWithOptionalGroup(string $s): void {
 	if (preg_match('/Price: (£|€)?\d+/', $s, $matches, PREG_UNMATCHED_AS_NULL)) {
 		// with PREG_UNMATCHED_AS_NULL the offset 1 will always exist. It is correct that it's nullable because it's optional though
-		assertType('array{string, non-empty-string|null}', $matches);
+		assertType("array{string, '£'|'€'|null}", $matches);
 	} else {
 		assertType('array{}', $matches);
 	}
-	assertType('array{}|array{string, non-empty-string|null}', $matches);
+	assertType("array{}|array{string, '£'|'€'|null}", $matches);
 }
 
 function bug11331a(string $url):void {
diff --git a/tests/PHPStan/Analyser/nsrt/preg_match_shapes.php b/tests/PHPStan/Analyser/nsrt/preg_match_shapes.php
index 001ec26d21..655c9d7d10 100644
--- a/tests/PHPStan/Analyser/nsrt/preg_match_shapes.php
+++ b/tests/PHPStan/Analyser/nsrt/preg_match_shapes.php
@@ -12,11 +12,11 @@ function doMatch(string $s): void {
 	assertType('array{}|array{string}', $matches);
 
 	if (preg_match('/Price: (£|€)\d+/', $s, $matches)) {
-		assertType('array{string, non-empty-string}', $matches);
+		assertType("array{string, '£'|'€'}", $matches);
 	} else {
 		assertType('array{}', $matches);
 	}
-	assertType('array{}|array{string, non-empty-string}', $matches);
+	assertType("array{}|array{string, '£'|'€'}", $matches);
 
 	if (preg_match('/Price: (£|€)(\d+)/i', $s, $matches)) {
 		assertType('array{string, non-empty-string, numeric-string}', $matches);
@@ -54,9 +54,9 @@ function doMatch(string $s): void {
 	assertType("array{}|array{0: string, 1: 'a', 2: string, 3: 'c', name?: non-empty-string, 4?: non-empty-string}", $matches);
 
 	if (preg_match('/(a|b)|(?:c)/', $s, $matches)) {
-		assertType('array{0: string, 1?: non-empty-string}', $matches);
+		assertType("array{0: string, 1?: 'a'|'b'}", $matches);
 	}
-	assertType('array{}|array{0: string, 1?: non-empty-string}', $matches);
+	assertType("array{}|array{0: string, 1?: 'a'|'b'}", $matches);
 
 	if (preg_match('/(foo)(bar)(baz)+/', $s, $matches)) {
 		assertType("array{string, 'foo', 'bar', non-falsy-string}", $matches);
@@ -356,30 +356,30 @@ function bug11291(string $s): void {
 function bug11323a(string $s): void
 {
 	if (preg_match('/Price: (?P<currency>£|€)\d+/', $s, $matches)) {
-		assertType('array{0: string, currency: non-empty-string, 1: non-empty-string}', $matches);
+		assertType("array{0: string, currency: '£'|'€', 1: '£'|'€'}", $matches);
 	} else {
 		assertType('array{}', $matches);
 	}
-	assertType('array{}|array{0: string, currency: non-empty-string, 1: non-empty-string}', $matches);
+	assertType("array{}|array{0: string, currency: '£'|'€', 1: '£'|'€'}", $matches);
 }
 
 function bug11323b(string $s): void
 {
 	if (preg_match('/Price: (?<currency>£|€)\d+/', $s, $matches)) {
-		assertType('array{0: string, currency: non-empty-string, 1: non-empty-string}', $matches);
+		assertType("array{0: string, currency: '£'|'€', 1: '£'|'€'}", $matches);
 	} else {
 		assertType('array{}', $matches);
 	}
-	assertType('array{}|array{0: string, currency: non-empty-string, 1: non-empty-string}', $matches);
+	assertType("array{}|array{0: string, currency: '£'|'€', 1: '£'|'€'}", $matches);
 }
 
 function unmatchedAsNullWithMandatoryGroup(string $s): void {
 	if (preg_match('/Price: (?<currency>£|€)\d+/', $s, $matches, PREG_UNMATCHED_AS_NULL)) {
-		assertType('array{0: string, currency: non-empty-string, 1: non-empty-string}', $matches);
+		assertType("array{0: string, currency: '£'|'€', 1: '£'|'€'}", $matches);
 	} else {
 		assertType('array{}', $matches);
 	}
-	assertType('array{}|array{0: string, currency: non-empty-string, 1: non-empty-string}', $matches);
+	assertType("array{}|array{0: string, currency: '£'|'€', 1: '£'|'€'}", $matches);
 }
 
 function (string $s): void {
@@ -608,17 +608,29 @@ function (string $s): void {
 };
 
 function (string $s): void {
-	if (preg_match('/Price: (a|0)/', $s, $matches)) {
+	if (preg_match('/Price: (a|bc?)/', $s, $matches)) {
 		assertType("array{string, non-empty-string}", $matches);
 	}
 };
 
 function (string $s): void {
-	if (preg_match('/Price: (aa|0)/', $s, $matches)) {
+	if (preg_match('/Price: (a|\d)/', $s, $matches)) {
 		assertType("array{string, non-empty-string}", $matches);
 	}
 };
 
+function (string $s): void {
+	if (preg_match('/Price: (a|0)/', $s, $matches)) {
+		assertType("array{string, '0'|'a'}", $matches);
+	}
+};
+
+function (string $s): void {
+	if (preg_match('/Price: (aa|0)/', $s, $matches)) {
+		assertType("array{string, '0'|'aa'}", $matches);
+	}
+};
+
 function (string $s): void {
 	if (preg_match('/( \d+ )/x', $s, $matches)) {
 		assertType('array{string, numeric-string}', $matches);