diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 79d74be7..2a6cd279 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -1076,6 +1076,18 @@ jobs:
             || { echo "FAIL: expected exactly one OWN001 (the uncleared timer)"; exit 1; }
           echo "$edges" | grep -q "pollB" \
             || { echo "FAIL: the leak must be the second (uncleared) interval"; exit 1; }
+      - name: Parser hardening — string literals, nested dep brackets, listener options
+        run: |
+          python frontend/ownts/ownts.py frontend/ownts/examples/EffectHardening.tsx \
+            -o "$RUNNER_TEMP/hard.facts.json"
+          hard=$(python -m ownlang ownir "$RUNNER_TEMP/hard.facts.json" || true)
+          echo "$hard"
+          # a string with commas/braces does not truncate the body (the timer is cleared);
+          # the leak is the options-dropped listener; the object dep fires EFF001 once
+          [ "$(echo "$hard" | grep -cE '\[(OWN|EFF|DI)[0-9]{3}\]')" -eq 2 ] \
+            || { echo "FAIL: expected one OWN001 (listener) + one EFF001 (object dep)"; exit 1; }
+          echo "$hard" | grep -q "scroll" \
+            || { echo "FAIL: the leak must be the options-dropped scroll listener"; exit 1; }
       - name: The clean fixture (cleanups + useMemo'd dep) is silent
         run: |
           python frontend/ownts/ownts.py frontend/ownts/examples/DashboardClean.tsx \
diff --git a/frontend/ownts/examples/EffectHardening.tsx b/frontend/ownts/examples/EffectHardening.tsx
new file mode 100644
index 00000000..60d12b27
--- /dev/null
+++ b/frontend/ownts/examples/EffectHardening.tsx
@@ -0,0 +1,31 @@
+// Parser-hardening cases (CodeRabbit): string literals must not truncate bodies or
+// split deps, deps brackets nest, and a listener is released only by a matching
+// target+handler+options removeEventListener. Run:
+//   python frontend/ownts/ownts.py frontend/ownts/examples/EffectHardening.tsx --check
+// Expect exactly: OWN001 (the options-dropped listener) + EFF001 (the object dep).
+import { useEffect } from "react";
+
+export function Hardening({ id }: { id: string }) {
+  // A string with commas and braces must not truncate the body or split the deps;
+  // the timer IS cleared, so this effect leaks nothing.
+  useEffect(() => {
+    const t = setInterval(() => fetch("/a,b,{c}"), 1000);
+    return () => clearInterval(t);
+  }, [id]);
+
+  // Listener added WITH capture, but cleanup drops the option -> different listener,
+  // still leaks (one OWN001).
+  useEffect(() => {
+    window.addEventListener("scroll", onScroll, true);
+    return () => window.removeEventListener("scroll", onScroll);
+  }, []);
+
+  // Nested-bracket dep parses (`items[0]` stays one entry); the object literal dep
+  // is unstable + IO -> exactly one EFF001 (items[0] is not identifier-like: silent).
+  const filters = { id };
+  useEffect(() => {
+    fetch("/x");
+  }, [filters, items[0]]);
+
+  return <div>hardening</div>;
+}
diff --git a/frontend/ownts/ownts.py b/frontend/ownts/ownts.py
index dccdb9f9..ef0f84c1 100644
--- a/frontend/ownts/ownts.py
+++ b/frontend/ownts/ownts.py
@@ -75,6 +75,45 @@ def _lhs_token(setup: str, pos: int) -> str | None:
     return m.group(1) if m else None
 
 
+def _capture_flag(opts: str) -> str:
+    """The capture flag an addEventListener/removeEventListener options arg implies —
+    the only field that identifies a listener for removal. `'true'`/`'false'`, or
+    `'unknown'` for a non-literal we cannot read. An omitted arg, or an options
+    object without a `capture` key, defaults to capture **false** (the DOM default);
+    `passive`/`once`/`signal` do not affect removal identity."""
+    o = opts.strip()
+    if o in ("", "false"):
+        return "false"
+    if o == "true":
+        return "true"
+    if o.startswith("{"):
+        m = re.search(r"\bcapture\s*:\s*(true|false)\b", o)
+        return m.group(1) if m else "false"
+    return "unknown"  # a variable/call — compare verbatim (equal only to itself)
+
+
+_LISTENER = re.compile(
+    r"\.\s*(?:add|remove)EventListener\s*\(\s*([^,]+?)\s*,\s*([A-Za-z_$][\w$.]*)\s*"
+    r"(?:,\s*([^)]+?))?\s*\)")
+
+
+def _listener_call(s: str) -> tuple[str, str, str] | None:
+    """Parse a `.addEventListener`/`.removeEventListener` head into the
+    (event, handler, capture) triple that identifies the listener for removal, or
+    None when it doesn't parse. `s` starts at the `.`."""
+    m = _LISTENER.match(s.lstrip())
+    if not m:
+        return None
+    return (m.group(1).strip(), m.group(2), _capture_flag(m.group(3) or ""))
+
+
+def _receiver(text: str, end: int) -> str:
+    """The receiver expression ending at `end` (just before `.addEventListener`),
+    allowing a member/index chain like `this.ref` or `nodes[i]`."""
+    m = re.search(r"([A-Za-z_$][\w$.\[\]]*)$", text[:end])
+    return m.group(1) if m else ""
+
+
 def _is_released(acq: Acquire, setup: str, pos: int, cleanup: str) -> bool:
     """Whether THIS acquire (at `pos` in `setup`) is released by the effect's cleanup
     — matched to its own handle, so two `setInterval`s with one `clearInterval` leave
@@ -88,12 +127,26 @@ def _is_released(acq: Acquire, setup: str, pos: int, cleanup: str) -> bool:
         tok = _lhs_token(setup, pos)
         return bool(tok and re.search(
             rf"\b{re.escape(tok)}\s*\.\s*(?:unsubscribe|remove)\s*\(", cleanup))
-    if acq.resource == "subscription":  # addEventListener(event, handler)
-        hm = re.search(r"addEventListener\s*\(\s*[^,]+,\s*([A-Za-z_$][\w$.]*)",
-                       setup[pos:])
-        handler = hm.group(1) if hm else None
-        return bool(handler and re.search(
-            rf"removeEventListener\s*\(\s*[^,]+,\s*{re.escape(handler)}\b", cleanup))
+    if acq.resource == "subscription":  # target.addEventListener(event, handler[, opts])
+        # The full listener key is (receiver, event, handler, capture). A listener is
+        # released ONLY by a removeEventListener whose whole key matches — a different
+        # event name, target, or capture flag is a different listener that still
+        # leaks. Fail closed: if the acquire's own target can't be identified, or no
+        # cleanup call matches every field, treat it as a leak.
+        a = _listener_call(setup[pos:])
+        if a is None:
+            return False
+        a_recv = _receiver(setup, pos)
+        if not a_recv:
+            return False
+        for rm in re.finditer(r"([A-Za-z_$][\w$.\[\]]*)\s*\.\s*removeEventListener\s*\(",
+                              cleanup):
+            if rm.group(1) != a_recv:
+                continue
+            b = _listener_call(cleanup[rm.start() + len(rm.group(1)):])
+            if b == a:
+                return True
+        return False
     return False
 
 # A React component is a function whose name is Capitalized (the JSX convention).
@@ -206,6 +259,68 @@ def _match_block(text: str, open_idx: int) -> int:
     return len(text)
 
 
+def _mask_strings(text: str) -> str:
+    """Blank the CONTENT of string/template literals — keeping the delimiters, the
+    length, and every newline — so the structural scanners (brace/paren/bracket
+    depth, top-level commas, the deps array) are never fooled by punctuation inside
+    a literal: `fetch("/a,b")`, `const s = "{"`, a `;` inside a string. Comments are
+    already gone (`_strip_comments`). Positions are preserved, so a match found on
+    the masked copy slices identically out of the original text."""
+    out = list(text)
+    i, n = 0, len(text)
+    while i < n:
+        c = text[i]
+        if c in "\"'`":
+            i += 1
+            while i < n and text[i] != c:
+                if text[i] == "\\" and i + 1 < n:
+                    for k in (i, i + 1):
+                        if text[k] != "\n":
+                            out[k] = " "
+                    i += 2
+                    continue
+                if text[i] != "\n":
+                    out[i] = " "
+                i += 1
+            i += 1  # past the closing delimiter (kept)
+        else:
+            i += 1
+    return "".join(out)
+
+
+def _match_pair(text: str, i: int, open_c: str, close_c: str) -> int:
+    """Index just past the `close_c` matching the `open_c` at/after `i`. Assumes
+    string contents are already masked (so no quote-skipping is needed here)."""
+    i = text.index(open_c, i)
+    depth = 0
+    while i < len(text):
+        if text[i] == open_c:
+            depth += 1
+        elif text[i] == close_c:
+            depth -= 1
+            if depth == 0:
+                return i + 1
+        i += 1
+    return len(text)
+
+
+def _split_top_commas(s: str) -> list[str]:
+    """Split on commas at bracket/paren/brace depth 0, so a dependency like
+    `items[i]` or `f(a, b)` stays one entry instead of being torn at its inner comma."""
+    parts: list[str] = []
+    depth, start = 0, 0
+    for j, c in enumerate(s):
+        if c in "([{":
+            depth += 1
+        elif c in ")]}":
+            depth -= 1
+        elif c == "," and depth == 0:
+            parts.append(s[start:j])
+            start = j + 1
+    parts.append(s[start:])
+    return [p.strip() for p in parts if p.strip()]
+
+
 def _component_at(text: str, idx: int) -> str:
     """Name of the React component enclosing position `idx` — the nearest preceding
     Capitalized function declaration. Falls back to a synthetic name."""
@@ -233,61 +348,85 @@ def _expr_end(text: str, i: int) -> int:
     return i
 
 
-def _effect_callback(text: str, after_open: int) -> tuple[str, int, list[str] | None, int]:
-    """Parse `useEffect(<cb>, [deps])` from just past the `(`. Returns
+def _effect_callback(masked: str, after_open: int) -> tuple[str, int, list[str] | None, int]:
+    """Parse `useEffect(<cb>, [deps])` from just past the `(`, over the STRING-MASKED
+    source (so literals never truncate a body or split a dep). Returns
     (body, body_start, deps, end). Handles BOTH a block `() => { ... }` and an
     expression `() => fetch(url)` callback — calling `_match_block` blindly on the
     latter would jump to an unrelated `{` or run off the end. `deps` is None when no
-    dependency array is present; `body` includes the braces for a block callback."""
-    arrow = text.find("=>", after_open)
+    dependency array is present; the array is matched by BALANCED brackets so a dep
+    like `items[i]` survives. `body` includes the braces for a block callback."""
+    arrow = masked.find("=>", after_open)
     i = (arrow + 2) if arrow != -1 else after_open
-    while i < len(text) and text[i] in " \t\r\n":
+    while i < len(masked) and masked[i] in " \t\r\n":
         i += 1
-    if i < len(text) and text[i] == "{":
-        end = _match_block(text, i)
+    if i < len(masked) and masked[i] == "{":
+        end = _match_block(masked, i)
     else:
-        end = _expr_end(text, i)
-    body = text[i:end]
-    deps_m = re.search(r"\s*,\s*\[([^\]]*)\]", text[end:end + 200])
-    deps = ([d.strip() for d in deps_m.group(1).split(",") if d.strip()]
-            if deps_m else None)
+        end = _expr_end(masked, i)
+    body = masked[i:end]
+    # the dependency array is the balanced `[ ... ]` after an optional `, `
+    deps: list[str] | None = None
+    j = end
+    while j < len(masked) and masked[j] in " \t\r\n":
+        j += 1
+    if j < len(masked) and masked[j] == ",":
+        j += 1
+        while j < len(masked) and masked[j] in " \t\r\n":
+            j += 1
+        if j < len(masked) and masked[j] == "[":
+            close = _match_pair(masked, j, "[", "]")
+            deps = _split_top_commas(masked[j + 1:close - 1])
     return body, i, deps, end
 
 
-def _split_cleanup(body: str) -> tuple[str, str]:
-    """Split an effect block body into (setup, cleanup). Cleanup is the block of the
-    effect's OWN top-level `return () => { ... }` — a `return ... =>` nested inside a
-    callback (brace-depth > 1) is NOT the effect cleanup and must not suppress a
-    leak. For an expression-bodied effect there is no cleanup."""
-    for m in re.finditer(r"return\s*(?:\(\s*\)|\w+)\s*=>", body):
-        prefix = body[:m.start()]
+def _cleanup_span(mbody: str) -> tuple[int, int] | None:
+    """The (start, end) span of the effect's OWN top-level cleanup within `mbody`
+    (the masked body), or None. A `return ... =>` nested inside a callback
+    (brace-depth > 1) is NOT the effect cleanup and must not suppress a leak. The
+    span is returned (not slices) so the caller can cut it out of BOTH the masked
+    body (for acquire scanning) and the original body (for event/string comparison)."""
+    for m in re.finditer(r"return\s*(?:\(\s*\)|\w+)\s*=>", mbody):
+        prefix = mbody[:m.start()]
         if prefix.count("{") - prefix.count("}") != 1:  # 1 == the effect body's own brace
             continue
-        brace = body.find("{", m.end())
+        brace = mbody.find("{", m.end())
         if brace == -1:
             # `return () => clearInterval(id)` — single-expression cleanup, no block.
-            nl = body.find("\n", m.end())
-            tail = body[m.end(): nl if nl != -1 else len(body)]
-            return body[: m.start()], tail
-        end = _match_block(body, brace)
-        return body[: m.start()] + body[end:], body[brace:end]
-    return body, ""
+            nl = mbody.find("\n", m.end())
+            return (m.start(), nl if nl != -1 else len(mbody))
+        return (m.start(), _match_block(mbody, brace))
+    return None
 
 
 def extract(path: str) -> list[Component]:
     text = _strip_comments(open(path, encoding="utf-8").read())
+    masked = _mask_strings(text)  # scan structure on this; show snippets from `text`
     comps: dict[str, Component] = {}
-    for eff in _USE_EFFECT.finditer(text):
-        body, body_start, _deps, _end = _effect_callback(text, eff.end())
-        setup, cleanup = _split_cleanup(body)
-        cname = _component_at(text, eff.start())
+    for eff in _USE_EFFECT.finditer(masked):
+        body_m, body_start, _deps, end = _effect_callback(masked, eff.end())
+        body_o = text[body_start:end]  # original (unmasked) body — same positions
+        span = _cleanup_span(body_m)
+        if span:
+            cs, ce = span
+            setup_m = body_m[:cs] + body_m[ce:]
+            setup_o = body_o[:cs] + body_o[ce:]
+            cleanup_o = body_o[cs:ce]
+        else:
+            setup_m, setup_o, cleanup_o = body_m, body_o, ""
+        cname = _component_at(masked, eff.start())
         comp = comps.setdefault(cname, Component(cname, path))
         for acq in ACQUIRES:
-            for hit in acq.pattern.finditer(setup):
-                line = text.count("\n", 0, body_start + hit.start()) + 1
-                released = _is_released(acq, setup, hit.start(), cleanup)
-                # the acquire expression, trimmed to the call head for a readable tag
-                snippet = setup[hit.start():].splitlines()[0].strip().rstrip("{").strip()
+            # find the acquire on the MASKED setup (a keyword inside a string is gone);
+            # decide release on the ORIGINAL setup/cleanup (so event-name strings and
+            # handles are intact for the full-key comparison).
+            for hit in acq.pattern.finditer(setup_m):
+                abs_pos = body_start + hit.start()
+                line = masked.count("\n", 0, abs_pos) + 1
+                released = _is_released(acq, setup_o, hit.start(), cleanup_o)
+                # the acquire expression for the tag — from the ORIGINAL text, so the
+                # message shows the real call (string args intact), trimmed to one line.
+                snippet = text[abs_pos:].splitlines()[0].strip().rstrip("{").strip()
                 comp.resources.append(
                     Resource(snippet or acq.name, line, released, acq.resource, acq.eff))
     return [c for c in comps.values() if c.resources]
@@ -361,8 +500,10 @@ def _classify_rhs(rhs: str) -> tuple[str, list[str]]:
 
 
 def _render_bindings(text: str) -> dict[str, list[dict]]:
-    """The render-scope binding table per component: only bindings declared DIRECTLY
-    in the component body (brace-depth 1). A `const filters = {...}` inside a
+    """The render-scope binding table per component, scanned over STRING-MASKED
+    source so a brace/quote inside a literal cannot shift the depth. Only bindings
+    declared DIRECTLY in the component body (brace-depth 1) count. A `const filters
+    = {...}` inside a
     `useEffect` callback, an event handler, or any nested block is NOT render scope —
     it must not shadow the real outer dependency of the same name and mint a false
     EFF001. Excluding a render-level `if`/`try` binding only costs a missed finding
@@ -393,16 +534,17 @@ def extract_effects(path: str) -> list[dict]:
     whether its body does network IO, and the render-scope binding table of the
     component it lives in. The core's effects analysis turns these into a verdict."""
     text = _strip_comments(open(path, encoding="utf-8").read())
-    binds_by_comp = _render_bindings(text)
+    masked = _mask_strings(text)
+    binds_by_comp = _render_bindings(masked)
     effects: list[dict] = []
-    for eff in _USE_EFFECT.finditer(text):
-        body, _start, deps, _end = _effect_callback(text, eff.end())
+    for eff in _USE_EFFECT.finditer(masked):
+        body, _start, deps, _end = _effect_callback(masked, eff.end())
         if deps is None:  # no dep array -> not an EFF001 candidate (by-design re-run cadence)
             continue
-        cname = _component_at(text, eff.start())
+        cname = _component_at(masked, eff.start())
         effects.append({
             "component": cname, "file": path,
-            "line": text.count("\n", 0, eff.start()) + 1,
+            "line": masked.count("\n", 0, eff.start()) + 1,
             "io": bool(_IO.search(body)),
             "deps": deps,
             "bindings": binds_by_comp.get(cname, []),
diff --git a/frontend/ownts/test_ownts.py b/frontend/ownts/test_ownts.py
index 255d5241..5c50a881 100644
--- a/frontend/ownts/test_ownts.py
+++ b/frontend/ownts/test_ownts.py
@@ -51,9 +51,47 @@ def main() -> int:
     edges = codes("EffectEdges.tsx")
     assert edges == ["OWN001"], f"EffectEdges -> {edges}"
 
+    # Parser hardening: a string with commas/braces does not truncate a body or
+    # split deps; deps brackets nest (`items[0]`); a listener is released only by a
+    # matching target+handler+options. -> one OWN001 (options dropped) + one EFF001.
+    hardening = codes("EffectHardening.tsx")
+    assert hardening == ["OWN001", "EFF001"], f"EffectHardening -> {hardening}"
+
+    # addEventListener release must match the receiver and capture/options, not just
+    # the handler (dropping `true` or changing the target still leaks).
+    sub = next(a for a in ownts.ACQUIRES if a.resource == "subscription")
+
+    def rel(setup: str, cleanup: str) -> bool:
+        return ownts._is_released(sub, setup, setup.index(".addEventListener"), cleanup)
+
+    assert rel('window.addEventListener("x", onX)', 'window.removeEventListener("x", onX)')
+    assert rel('window.addEventListener("x", onX, true)',
+               'window.removeEventListener("x", onX, true)')
+    assert not rel('window.addEventListener("x", onX, true)',
+                   'window.removeEventListener("x", onX)'), "dropped options must still leak"
+    assert not rel('window.addEventListener("x", onX)',
+                   'window.removeEventListener("x", onX, true)'), \
+        "omitted capture (false) is not released by remove(..., true)"
+    assert rel('window.addEventListener("x", onX, {capture: true})',
+               'window.removeEventListener("x", onX, true)'), \
+        "{capture:true} and true are the same listener"
+    assert rel('window.addEventListener("x", onX, {passive: true})',
+               'window.removeEventListener("x", onX)'), \
+        "a non-capture option (passive) does not change removal identity"
+    assert not rel('el.addEventListener("x", onX)',
+                   'other.removeEventListener("x", onX)'), "wrong target must still leak"
+    assert not rel('window.addEventListener("scroll", onX)',
+                   'window.removeEventListener("resize", onX)'), \
+        "a different event name is a different listener (still leaks)"
+    assert rel('nodes[i].addEventListener("x", onX)',
+               'nodes[i].removeEventListener("x", onX)'), "indexed receiver matches itself"
+    assert not rel('nodes[i].addEventListener("x", onX)',
+                   'nodes[j].removeEventListener("x", onX)'), \
+        "a different index is a different target (still leaks)"
+
     print("OwnTS spike OK: leaky=3xOWN001+EFF001, clean=0, kinds=timer/subscribe/"
-          "subscription, EffectStorm=2xEFF001, EffectEdges=1xOWN001 (per-resource "
-          "cleanup + render-scope-only bindings).")
+          "subscription, EffectStorm=2xEFF001, EffectEdges=1xOWN001, "
+          "EffectHardening=OWN001+EFF001 (literal-proof parser + strict listener match).")
     return 0