diff --git a/phpcs-sniffs/Formidable/Sniffs/Commenting/AlignFilterParamTypesWithFunctionSniff.php b/phpcs-sniffs/Formidable/Sniffs/Commenting/AlignFilterParamTypesWithFunctionSniff.php
new file mode 100644
index 0000000000..38e426cd3f
--- /dev/null
+++ b/phpcs-sniffs/Formidable/Sniffs/Commenting/AlignFilterParamTypesWithFunctionSniff.php
@@ -0,0 +1,405 @@
+<?php
+/**
+ * Ensures inline filter docblocks reuse the function's @param types when the
+ * referenced parameter hasn't been modified before the filter call.
+ *
+ * @package Formidable\Sniffs\Commenting
+ */
+
+namespace Formidable\Sniffs\Commenting;
+
+use PHP_CodeSniffer\Files\File;
+use PHP_CodeSniffer\Sniffs\Sniff;
+
+/**
+ * Detects inline filter docblocks where @param types diverge from the function docblock.
+ */
+class AlignFilterParamTypesWithFunctionSniff implements Sniff {
+
+	/**
+	 * Filter helper functions we care about.
+	 *
+	 * @var array
+	 */
+	private $filterFunctions = array(
+		'apply_filters',
+		'apply_filters_ref_array',
+		'apply_filters_deprecated',
+	);
+
+	/**
+	 * Tokens that represent assignments.
+	 *
+	 * @var array
+	 */
+	private $assignmentTokens = array(
+		T_EQUAL,
+		T_PLUS_EQUAL,
+		T_MINUS_EQUAL,
+		T_MUL_EQUAL,
+		T_DIV_EQUAL,
+		T_CONCAT_EQUAL,
+		T_MOD_EQUAL,
+		T_AND_EQUAL,
+		T_OR_EQUAL,
+		T_XOR_EQUAL,
+		T_SL_EQUAL,
+		T_SR_EQUAL,
+	);
+
+	/**
+	 * {@inheritDoc}
+	 */
+	public function register() {
+		return array( T_FUNCTION );
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	public function process( File $phpcsFile, $stackPtr ) {
+		$tokens = $phpcsFile->getTokens();
+
+		if ( ! isset( $tokens[ $stackPtr ]['scope_opener'], $tokens[ $stackPtr ]['scope_closer'] ) ) {
+			return;
+		}
+
+		$functionDocblock = $this->findFunctionDocblock( $phpcsFile, $stackPtr );
+
+		if ( false === $functionDocblock ) {
+			return;
+		}
+
+		$functionParams = $this->getDocblockParamTags( $phpcsFile, $functionDocblock );
+
+		if ( empty( $functionParams ) ) {
+			return;
+		}
+
+		$scopeStart = $tokens[ $stackPtr ]['scope_opener'];
+		$scopeEnd   = $tokens[ $stackPtr ]['scope_closer'];
+
+		for ( $i = $scopeStart + 1; $i < $scopeEnd; $i++ ) {
+			if ( $tokens[ $i ]['code'] !== T_DOC_COMMENT_OPEN_TAG ) {
+				continue;
+			}
+
+			if ( ! isset( $tokens[ $i ]['comment_closer'] ) ) {
+				continue;
+			}
+
+			$docblockClose = $tokens[ $i ]['comment_closer'];
+			$nextToken     = $phpcsFile->findNext( T_WHITESPACE, $docblockClose + 1, $scopeEnd, true );
+
+			if ( false === $nextToken || $tokens[ $nextToken ]['code'] !== T_RETURN ) {
+				$i = $docblockClose;
+				continue;
+			}
+
+			$filterCall = $this->findFilterCallAfterReturn( $phpcsFile, $nextToken, $scopeEnd );
+
+			if ( false === $filterCall ) {
+				$i = $docblockClose;
+				continue;
+			}
+
+			$inlineParams = $this->getDocblockParamTags( $phpcsFile, $i );
+
+			if ( empty( $inlineParams ) ) {
+				$i = $docblockClose;
+				continue;
+			}
+
+			foreach ( $inlineParams as $paramName => $paramInfo ) {
+				if ( ! isset( $functionParams[ $paramName ] ) ) {
+					continue;
+				}
+
+				if ( empty( $functionParams[ $paramName ]['normalized'] ) || empty( $paramInfo['normalized'] ) ) {
+					continue;
+				}
+
+				if ( $this->variableModifiedBeforeDocblock( $phpcsFile, $paramName, $scopeStart, $i ) ) {
+					continue;
+				}
+
+				if ( $this->typesMatch( $functionParams[ $paramName ]['normalized'], $paramInfo['normalized'] ) ) {
+					continue;
+				}
+
+				$fix = $phpcsFile->addFixableError(
+					'Filter docblock type for %s should match function @param type "%s" since the variable is unmodified before the filter.',
+					$paramInfo['token'],
+					'FilterParamTypeMismatch',
+					array(
+						$paramName,
+						$functionParams[ $paramName ]['type'],
+					)
+				);
+
+				if ( true === $fix ) {
+					$this->replaceParamType( $phpcsFile, $paramInfo['token'], $functionParams[ $paramName ]['type'] );
+				}
+			}
+
+			$i = $docblockClose;
+		}
+	}
+
+	/**
+	 * Find the docblock that documents the function itself.
+	 *
+	 * @param File $phpcsFile File reference.
+	 * @param int  $stackPtr  Function pointer.
+	 *
+	 * @return false|int
+	 */
+	private function findFunctionDocblock( File $phpcsFile, $stackPtr ) {
+		$tokens = $phpcsFile->getTokens();
+		$ignore = array(
+			T_WHITESPACE,
+			T_STATIC,
+			T_PUBLIC,
+			T_PRIVATE,
+			T_PROTECTED,
+			T_ABSTRACT,
+			T_FINAL,
+			T_ATTRIBUTE,
+		);
+
+		$prev = $phpcsFile->findPrevious( $ignore, $stackPtr - 1, null, true );
+
+		if ( false !== $prev && $tokens[ $prev ]['code'] === T_DOC_COMMENT_CLOSE_TAG ) {
+			return $tokens[ $prev ]['comment_opener'];
+		}
+
+		return false;
+	}
+
+	/**
+	 * Parse @param tags within a docblock.
+	 *
+	 * @param File $phpcsFile  File reference.
+	 * @param int  $docblockPt Docblock opener pointer.
+	 *
+	 * @return array
+	 */
+	private function getDocblockParamTags( File $phpcsFile, $docblockPt ) {
+		$tokens = $phpcsFile->getTokens();
+
+		if ( ! isset( $tokens[ $docblockPt ]['comment_closer'] ) ) {
+			return array();
+		}
+
+		$closer = $tokens[ $docblockPt ]['comment_closer'];
+		$params = array();
+
+		for ( $i = $docblockPt; $i <= $closer; $i++ ) {
+			if ( $tokens[ $i ]['code'] !== T_DOC_COMMENT_TAG || '@param' !== $tokens[ $i ]['content'] ) {
+				continue;
+			}
+
+			$stringPtr = $phpcsFile->findNext( T_DOC_COMMENT_STRING, $i + 1, $closer );
+
+			if ( false === $stringPtr ) {
+				continue;
+			}
+
+			$content = trim( $tokens[ $stringPtr ]['content'] );
+
+			if ( ! preg_match( '/^([^\s]+)\s+(\$\w+)/', $content, $matches ) ) {
+				continue;
+			}
+
+			$type      = trim( $matches[1] );
+			$paramName = $matches[2];
+
+			$params[ $paramName ] = array(
+				'type'       => $type,
+				'normalized' => $this->normalizeTypeList( $type ),
+				'token'      => $stringPtr,
+			);
+		}
+
+		return $params;
+	}
+
+	/**
+	 * Find the filter call after a return statement.
+	 *
+	 * @param File $phpcsFile File reference.
+	 * @param int  $returnPtr Return token pointer.
+	 * @param int  $scopeEnd  Function scope end.
+	 *
+	 * @return false|int
+	 */
+	private function findFilterCallAfterReturn( File $phpcsFile, $returnPtr, $scopeEnd ) {
+		$tokens = $phpcsFile->getTokens();
+
+		for ( $i = $returnPtr + 1; $i < $scopeEnd; $i++ ) {
+			$code = $tokens[ $i ]['code'];
+
+			if ( $code === T_SEMICOLON ) {
+				break;
+			}
+
+			if ( $code === T_STRING && in_array( $tokens[ $i ]['content'], $this->filterFunctions, true ) ) {
+				return $i;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Determine if a variable is modified before a certain docblock.
+	 *
+	 * @param File   $phpcsFile  File reference.
+	 * @param string $paramName  Parameter name (with $).
+	 * @param int    $scopeStart Function scope start brace.
+	 * @param int    $docblockPt Docblock pointer.
+	 *
+	 * @return bool
+	 */
+	private function variableModifiedBeforeDocblock( File $phpcsFile, $paramName, $scopeStart, $docblockPt ) {
+		$tokens = $phpcsFile->getTokens();
+
+		for ( $i = $scopeStart + 1; $i < $docblockPt; $i++ ) {
+			if ( $tokens[ $i ]['code'] !== T_VARIABLE || $tokens[ $i ]['content'] !== $paramName ) {
+				continue;
+			}
+
+			$prev = $phpcsFile->findPrevious( T_WHITESPACE, $i - 1, null, true );
+
+			if ( false !== $prev && in_array( $tokens[ $prev ]['code'], array( T_INC, T_DEC ), true ) ) {
+				return true;
+			}
+
+			$next = $phpcsFile->findNext( T_WHITESPACE, $i + 1, null, true );
+
+			if ( false === $next ) {
+				continue;
+			}
+
+			if ( in_array( $tokens[ $next ]['code'], $this->assignmentTokens, true ) ) {
+				return true;
+			}
+
+			if ( in_array( $tokens[ $next ]['code'], array( T_INC, T_DEC ), true ) ) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Normalize a set of type strings.
+	 *
+	 * @param string $typeString Type string from a docblock.
+	 *
+	 * @return array
+	 */
+	private function normalizeTypeList( $typeString ) {
+		$typeString = trim( $typeString );
+
+		if ( '' === $typeString ) {
+			return array();
+		}
+
+		if ( strpos( $typeString, '?' ) === 0 ) {
+			$typeString = 'null|' . substr( $typeString, 1 );
+		}
+
+		$parts      = explode( '|', $typeString );
+		$normalized = array();
+
+		foreach ( $parts as $part ) {
+			$single = $this->normalizeType( $part );
+
+			if ( '' !== $single ) {
+				$normalized[] = $single;
+			}
+		}
+
+		$normalized = array_values( array_unique( $normalized ) );
+		sort( $normalized );
+
+		return $normalized;
+	}
+
+	/**
+	 * Normalize a single type entry for comparison.
+	 *
+	 * @param string $type Type fragment.
+	 *
+	 * @return string
+	 */
+	private function normalizeType( $type ) {
+		$type = trim( $type );
+
+		if ( '' === $type ) {
+			return '';
+		}
+
+		if ( substr( $type, -2 ) === '[]' ) {
+			return 'array';
+		}
+
+		if ( preg_match( '/^array\s*[<{]/i', $type ) ) {
+			return 'array';
+		}
+
+		$lower = strtolower( ltrim( $type, '\\' ) );
+
+		$aliases = array(
+			'integer' => 'int',
+			'boolean' => 'bool',
+			'double'  => 'float',
+			'real'    => 'float',
+			'number'  => 'float',
+			'true'    => 'bool',
+		);
+
+		if ( isset( $aliases[ $lower ] ) ) {
+			return $aliases[ $lower ];
+		}
+
+		return $lower;
+	}
+
+	/**
+	 * Compare two normalized type lists.
+	 *
+	 * @param array $functionTypes Function doc types.
+	 * @param array $inlineTypes   Inline doc types.
+	 *
+	 * @return bool
+	 */
+	private function typesMatch( array $functionTypes, array $inlineTypes ) {
+		return $functionTypes === $inlineTypes;
+	}
+
+	/**
+	 * Replace the @param type in an inline docblock.
+	 *
+	 * @param File   $phpcsFile File reference.
+	 * @param int    $tokenPtr  Doc comment string pointer.
+	 * @param string $newType   Replacement type string.
+	 *
+	 * @return void
+	 */
+	private function replaceParamType( File $phpcsFile, $tokenPtr, $newType ) {
+		$tokens   = $phpcsFile->getTokens();
+		$content  = $tokens[ $tokenPtr ]['content'];
+		$newValue = preg_replace( '/^[^\s]+/', $newType, $content, 1 );
+
+		if ( null === $newValue ) {
+			return;
+		}
+
+		$phpcsFile->fixer->beginChangeset();
+		$phpcsFile->fixer->replaceToken( $tokenPtr, $newValue );
+		$phpcsFile->fixer->endChangeset();
+	}
+}
diff --git a/phpcs-sniffs/Formidable/ruleset.xml b/phpcs-sniffs/Formidable/ruleset.xml
index bae2d5326e..9965585dd3 100644
--- a/phpcs-sniffs/Formidable/ruleset.xml
+++ b/phpcs-sniffs/Formidable/ruleset.xml
@@ -48,6 +48,7 @@
 	<rule ref="Formidable.CodeAnalysis.PreferKsesEcho" />
 	<rule ref="Formidable.CodeAnalysis.PreferFrmAppHelper" />
 	<rule ref="Formidable.CodeAnalysis.InlineFrmSettingsReturn" />
+	<rule ref="Formidable.Commenting.AlignFilterParamTypesWithFunction" />
 	<rule ref="Formidable.CodeAnalysis.PreferPositiveTernaryCondition" />
 	<rule ref="Formidable.CodeAnalysis.StrictComparisonForIntFunctions" />
 	<rule ref="Formidable.CodeAnalysis.MoveSimpleCheckBeforeExpensiveCall" />