diff --git a/src/Files/File.php b/src/Files/File.php
index 42e1a39f9b..83b4d15728 100644
--- a/src/Files/File.php
+++ b/src/Files/File.php
@@ -2443,8 +2443,8 @@ public function findNext(
     /**
      * Returns the position of the first non-whitespace token in a statement.
      *
-     * @param int              $start  The position to start searching from in the token stack.
-     * @param int|string|array $ignore Token types that should not be considered stop points.
+     * @param int                   $start  The position to start searching from in the token stack.
+     * @param int|string|array|null $ignore Token types that should not be considered stop points.
      *
      * @return int
      */
@@ -2634,8 +2634,8 @@ public function findStartOfStatement($start, $ignore=null)
     /**
      * Returns the position of the last non-whitespace token in a statement.
      *
-     * @param int              $start  The position to start searching from in the token stack.
-     * @param int|string|array $ignore Token types that should not be considered stop points.
+     * @param int                   $start  The position to start searching from in the token stack.
+     * @param int|string|array|null $ignore Token types that should not be considered stop points.
      *
      * @return int
      */
@@ -2756,7 +2756,7 @@ public function findEndOfStatement($start, $ignore=null)
      *                                  token stack.
      * @param bool             $exclude If true, find the token that is NOT of
      *                                  the types specified in $types.
-     * @param string           $value   The value that the token must be equal to.
+     * @param string|null      $value   The value that the token must be equal to.
      *                                  If value is omitted, tokens with any value will
      *                                  be returned.
      *
diff --git a/src/Files/FileList.php b/src/Files/FileList.php
index 48c86c5861..6c8b993125 100644
--- a/src/Files/FileList.php
+++ b/src/Files/FileList.php
@@ -110,8 +110,8 @@ public function __construct(Config $config, Ruleset $ruleset)
      * If a file object has already been created, it can be passed here.
      * If it is left NULL, it will be created when accessed.
      *
-     * @param string                      $path The path to the file being added.
-     * @param \PHP_CodeSniffer\Files\File $file The file being added.
+     * @param string                           $path The path to the file being added.
+     * @param \PHP_CodeSniffer\Files\File|null $file The file being added.
      *
      * @return void
      */
diff --git a/src/Fixer.php b/src/Fixer.php
index 3e1f482a72..bbc2506ac7 100644
--- a/src/Fixer.php
+++ b/src/Fixer.php
@@ -222,10 +222,10 @@ public function fixFile()
     /**
      * Generates a text diff of the original file and the new content.
      *
-     * @param string  $filePath Optional file path to diff the file against.
-     *                          If not specified, the original version of the
-     *                          file will be used.
-     * @param boolean $colors   Print coloured output or not.
+     * @param string|null $filePath Optional file path to diff the file against.
+     *                              If not specified, the original version of the
+     *                              file will be used.
+     * @param boolean     $colors   Print coloured output or not.
      *
      * @return string
      *
@@ -698,10 +698,10 @@ public function revertToken($stackPtr)
     /**
      * Replace the content of a token with a part of its current content.
      *
-     * @param int $stackPtr The position of the token in the token stack.
-     * @param int $start    The first character to keep.
-     * @param int $length   The number of characters to keep. If NULL, the content of
-     *                      the token from $start to the end of the content is kept.
+     * @param int      $stackPtr The position of the token in the token stack.
+     * @param int      $start    The first character to keep.
+     * @param int|null $length   The number of characters to keep. If NULL, the content of
+     *                           the token from $start to the end of the content is kept.
      *
      * @return bool If the change was accepted.
      */
diff --git a/src/Ruleset.php b/src/Ruleset.php
index 7614998171..6118c778c9 100644
--- a/src/Ruleset.php
+++ b/src/Ruleset.php
@@ -1698,8 +1698,8 @@ public function setSniffProperty($sniffClass, $name, $settings)
      * Optionally takes a listener to get ignore patterns specified
      * for that sniff only.
      *
-     * @param string $listener The listener to get patterns for. If NULL, all
-     *                         patterns are returned.
+     * @param string|null $listener The listener to get patterns for. If NULL, all
+     *                              patterns are returned.
      *
      * @return array
      */
@@ -1724,8 +1724,8 @@ public function getIgnorePatterns($listener=null)
      * Optionally takes a listener to get include patterns specified
      * for that sniff only.
      *
-     * @param string $listener The listener to get patterns for. If NULL, all
-     *                         patterns are returned.
+     * @param string|null $listener The listener to get patterns for. If NULL, all
+     *                              patterns are returned.
      *
      * @return array
      */
diff --git a/src/Standards/Generic/Sniffs/Formatting/MultipleStatementAlignmentSniff.php b/src/Standards/Generic/Sniffs/Formatting/MultipleStatementAlignmentSniff.php
index 8916659a9a..2e128adc69 100644
--- a/src/Standards/Generic/Sniffs/Formatting/MultipleStatementAlignmentSniff.php
+++ b/src/Standards/Generic/Sniffs/Formatting/MultipleStatementAlignmentSniff.php
@@ -92,7 +92,7 @@ public function process(File $phpcsFile, $stackPtr)
      * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
      * @param int                         $stackPtr  The position of the current token
      *                                               in the stack passed in $tokens.
-     * @param int                         $end       The token where checking should end.
+     * @param int|null                    $end       The token where checking should end.
      *                                               If NULL, the entire file will be checked.
      *
      * @return int
diff --git a/src/Standards/Generic/Sniffs/PHP/DeprecatedFunctionsSniff.php b/src/Standards/Generic/Sniffs/PHP/DeprecatedFunctionsSniff.php
index 44efd53afd..fe2ceb32e0 100644
--- a/src/Standards/Generic/Sniffs/PHP/DeprecatedFunctionsSniff.php
+++ b/src/Standards/Generic/Sniffs/PHP/DeprecatedFunctionsSniff.php
@@ -53,7 +53,7 @@ public function __construct()
      * @param int                         $stackPtr  The position of the forbidden function
      *                                               in the token array.
      * @param string                      $function  The name of the forbidden function.
-     * @param string                      $pattern   The pattern used for the match.
+     * @param string|null                 $pattern   The pattern used for the match.
      *
      * @return void
      */
diff --git a/src/Standards/Generic/Sniffs/PHP/ForbiddenFunctionsSniff.php b/src/Standards/Generic/Sniffs/PHP/ForbiddenFunctionsSniff.php
index 2137e5a52d..ab6c97dfe3 100644
--- a/src/Standards/Generic/Sniffs/PHP/ForbiddenFunctionsSniff.php
+++ b/src/Standards/Generic/Sniffs/PHP/ForbiddenFunctionsSniff.php
@@ -206,7 +206,7 @@ public function process(File $phpcsFile, $stackPtr)
      * @param int                         $stackPtr  The position of the forbidden function
      *                                               in the token array.
      * @param string                      $function  The name of the forbidden function.
-     * @param string                      $pattern   The pattern used for the match.
+     * @param string|null                 $pattern   The pattern used for the match.
      *
      * @return void
      */
diff --git a/src/Tokenizers/Tokenizer.php b/src/Tokenizers/Tokenizer.php
index fe3d05e83f..af7c110e61 100644
--- a/src/Tokenizers/Tokenizer.php
+++ b/src/Tokenizers/Tokenizer.php
@@ -579,10 +579,10 @@ private function createPositionMap()
      * is placed into an orig_content index and the new token length is also
      * set in the length index.
      *
-     * @param array  $token    The token to replace tabs inside.
-     * @param string $prefix   The character to use to represent the start of a tab.
-     * @param string $padding  The character to use to represent the end of a tab.
-     * @param int    $tabWidth The number of spaces each tab represents.
+     * @param array    $token    The token to replace tabs inside.
+     * @param string   $prefix   The character to use to represent the start of a tab.
+     * @param string   $padding  The character to use to represent the end of a tab.
+     * @param int|null $tabWidth The number of spaces each tab represents.
      *
      * @return void
      */
diff --git a/src/Util/Cache.php b/src/Util/Cache.php
index e0ee9c8b4b..b132018fa0 100644
--- a/src/Util/Cache.php
+++ b/src/Util/Cache.php
@@ -300,8 +300,8 @@ public static function save()
     /**
      * Retrieves a single entry from the cache.
      *
-     * @param string $key The key of the data to get. If NULL,
-     *                    everything in the cache is returned.
+     * @param string|null $key The key of the data to get. If NULL,
+     *                         everything in the cache is returned.
      *
      * @return mixed
      */
@@ -323,9 +323,9 @@ public static function get($key=null)
     /**
      * Retrieves a single entry from the cache.
      *
-     * @param string $key   The key of the data to set. If NULL,
-     *                      sets the entire cache.
-     * @param mixed  $value The value to set.
+     * @param string|null $key   The key of the data to set. If NULL,
+     *                           sets the entire cache.
+     * @param mixed       $value The value to set.
      *
      * @return void
      */
diff --git a/src/Util/Tokens.php b/src/Util/Tokens.php
index 525b5b6329..081b6ab11b 100644
--- a/src/Util/Tokens.php
+++ b/src/Util/Tokens.php
@@ -804,8 +804,8 @@ public static function tokenName($token)
      * @param array<int|string> $tokens The token types to get the highest weighted
      *                                  type for.
      *
-     * @return int The highest weighted token.
-     *             On equal "weight", returns the first token of that particular weight.
+     * @return int|string The highest weighted token.
+     *                    On equal "weight", returns the first token of that particular weight.
      */
     public static function getHighestWeightedToken(array $tokens)
     {