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diff --git a/examples/my_line_rules.py b/examples/my_line_rules.py
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+from gitlint.rules import LineRule, RuleViolation, CommitMessageTitle
+from gitlint.options import ListOption
+
+"""
+Full details on user-defined rules: https://jorisroovers.com/gitlint/user_defined_rules
+
+The SpecialChars class below is an example of a user-defined LineRule. Line rules are gitlint rules that only act on a
+single line at once. Once the rule is discovered, gitlint will automatically take care of applying this rule
+against each line of the commit message title or body (whether it is applied to the title or body is determined by the
+`target` attribute of the class).
+
+A LineRule contrasts with a CommitRule (see examples/my_commit_rules.py) in that a commit rule is only applied once on
+an entire commit. This allows commit rules to implement more complex checks that span multiple lines and/or checks
+that should only be done once per gitlint run.
+
+While every LineRule can be implemented as a CommitRule, it's usually easier and more concise to go with a LineRule if
+that fits your needs.
+"""
+
+
+class SpecialChars(LineRule):
+    """This rule will enforce that the commit message title does not contain any of the following characters:
+    $^%@!*()"""
+
+    # A rule MUST have a human friendly name
+    name = "title-no-special-chars"
+
+    # A rule MUST have a *unique* id, we recommend starting with UL (for User-defined Line-rule), but this can
+    # really be anything.
+    id = "UL1"
+
+    # A line-rule MUST have a target (not required for CommitRules).
+    target = CommitMessageTitle
+
+    # A rule MAY have an option_spec if its behavior should be configurable.
+    options_spec = [
+        ListOption(
+            "special-chars",
+            ["$", "^", "%", "@", "!", "*", "(", ")"],
+            "Comma separated list of characters that should not occur in the title",
+        )
+    ]
+
+    def validate(self, line, _commit):
+        self.log.debug("SpecialChars: This will be visible when running `gitlint --debug`")
+
+        violations = []
+        # options can be accessed by looking them up by their name in self.options
+        for char in self.options["special-chars"].value:
+            if char in line:
+                msg = f"Title contains the special character '{char}'"
+                violation = RuleViolation(self.id, msg, line)
+                violations.append(violation)
+
+        return violations