FAILURE MAP
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FA-61771 / Options payoff and settlement / Open access

Early call exercise before an ex-dividend date: the dividend is compared with the whole call price · case 01

Deep in-the-money calls are never exercised early.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The comparison uses the full premium instead of its time value.

VERIFIED REPAIR

Compare the dividend with price minus intrinsic.

Unsuccessful approach: Comparing with intrinsic value is unrelated to what exercise forfeits.

Case contract

Inputs call price, spot, strike, dividend and whether today is the last cum-dividend day. Exercise only on the last cum-dividend day, only if the call is in the money, and only if the dividend is strictly greater than the call's extrinsic value (price - intrinsic). Amounts compared exactly in cents. Return true/false.

Why this case matters

Option expiry, exercise and settlement engines move cash and shares; a wrong branch misstates obligations.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(call_price, S, K, dividend, last_cum_day):
    c = round(call_price * 100)
    intrinsic = max(round(S * 100) - round(K * 100), 0)
    if not last_cum_day or intrinsic == 0:
        return False
    extrinsic = c - intrinsic
    return round(dividend * 100) > c
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression extrinsic measure 1', [15.25, 105.0, 90.0, 1.0, True], True], ['regression extrinsic measure 2', [9.5, 98.0, 90.0, 1.51, True], True], ['partial repair probe 1', [8.5, 98.0, 90.0, 0.51, True], True], ['partial repair probe 2', [5.05, 105.0, 100.0, 0.25, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [9.0, 98.0, 90.0, 1.0, False], False], ['normal control 2', [1.0, 98.0, 100.0, 1.0, True], False], ['normal control 3', [0.25, 105.0, 110.0, 0.25, True], False]], [['regression extrinsic measure 1', [8.25, 98.0, 90.0, 1.0, True], True], ['regression extrinsic measure 2', [31.5, 120.0, 90.0, 1.51, True], True], ['partial repair probe 1', [30.05, 120.0, 90.0, 1.0, True], True], ['partial repair probe 2', [10.05, 100.0, 90.0, 0.25, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [0.25, 98.0, 100.0, 1.0, True], False], ['normal control 2', [1.5, 100.0, 100.0, 1.5, True], False], ['normal control 3', [8.5, 98.0, 90.0, 0.5, False], False]], [['regression extrinsic measure 1', [9.5, 98.0, 90.0, 1.51, True], True], ['regression extrinsic measure 2', [5.25, 105.0, 100.0, 0.26, True], True], ['partial repair probe 1', [10.25, 100.0, 90.0, 1.0, True], True], ['partial repair probe 2', [15.05, 105.0, 90.0, 0.060000000000000005, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [0.05, 98.0, 110.0, 0.5, True], False], ['normal control 2', [1.0, 100.0, 100.0, 1.0, True], False], ['normal control 3', [15.5, 105.0, 90.0, 0.5, True], False]], [['regression extrinsic measure 1', [15.05, 105.0, 90.0, 0.25, True], True], ['regression extrinsic measure 2', [30.05, 120.0, 90.0, 1.0, True], True], ['partial repair probe 1', [16.5, 105.0, 90.0, 1.51, True], True], ['partial repair probe 2', [15.05, 105.0, 90.0, 0.060000000000000005, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [21.0, 120.0, 100.0, 0.25, False], False], ['normal control 2', [6.0, 105.0, 100.0, 0.25, True], False], ['normal control 3', [6.5, 105.0, 100.0, 0.5, False], False]], [['regression extrinsic measure 1', [6.5, 105.0, 100.0, 1.51, True], True], ['regression extrinsic measure 2', [11.0, 100.0, 90.0, 1.01, True], True], ['partial repair probe 1', [10.05, 100.0, 90.0, 1.0, True], True], ['partial repair probe 2', [9.0, 98.0, 90.0, 1.01, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [30.25, 120.0, 90.0, 0.25, True], False], ['normal control 2', [1.5, 98.0, 100.0, 1.51, True], False], ['normal control 3', [1.0, 105.0, 110.0, 1.0, True], False]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression extrinsic measure 1FalseTrueFailed
regression extrinsic measure 2FalseTrueFailed
partial repair probe 1FalseTrueFailed
partial repair probe 2FalseTrueFailed
boundary control 1FalseFalsePassed
normal control 1FalseFalsePassed
normal control 2FalseFalsePassed
normal control 3FalseFalsePassed

SHA-256 / cb8a1e1b20e9f5a876402fc453a234ee1193a0d996454961004ab0d8c5d55a9a

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(call_price, S, K, dividend, last_cum_day):
    c = round(call_price * 100)
    intrinsic = max(round(S * 100) - round(K * 100), 0)
    if not last_cum_day or intrinsic == 0:
        return False
    extrinsic = c - intrinsic
    return round(dividend * 100) > intrinsic
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression extrinsic measure 1', [15.25, 105.0, 90.0, 1.0, True], True], ['regression extrinsic measure 2', [9.5, 98.0, 90.0, 1.51, True], True], ['partial repair probe 1', [8.5, 98.0, 90.0, 0.51, True], True], ['partial repair probe 2', [5.05, 105.0, 100.0, 0.25, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [9.0, 98.0, 90.0, 1.0, False], False], ['normal control 2', [1.0, 98.0, 100.0, 1.0, True], False], ['normal control 3', [0.25, 105.0, 110.0, 0.25, True], False]], [['regression extrinsic measure 1', [8.25, 98.0, 90.0, 1.0, True], True], ['regression extrinsic measure 2', [31.5, 120.0, 90.0, 1.51, True], True], ['partial repair probe 1', [30.05, 120.0, 90.0, 1.0, True], True], ['partial repair probe 2', [10.05, 100.0, 90.0, 0.25, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [0.25, 98.0, 100.0, 1.0, True], False], ['normal control 2', [1.5, 100.0, 100.0, 1.5, True], False], ['normal control 3', [8.5, 98.0, 90.0, 0.5, False], False]], [['regression extrinsic measure 1', [9.5, 98.0, 90.0, 1.51, True], True], ['regression extrinsic measure 2', [5.25, 105.0, 100.0, 0.26, True], True], ['partial repair probe 1', [10.25, 100.0, 90.0, 1.0, True], True], ['partial repair probe 2', [15.05, 105.0, 90.0, 0.060000000000000005, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [0.05, 98.0, 110.0, 0.5, True], False], ['normal control 2', [1.0, 100.0, 100.0, 1.0, True], False], ['normal control 3', [15.5, 105.0, 90.0, 0.5, True], False]], [['regression extrinsic measure 1', [15.05, 105.0, 90.0, 0.25, True], True], ['regression extrinsic measure 2', [30.05, 120.0, 90.0, 1.0, True], True], ['partial repair probe 1', [16.5, 105.0, 90.0, 1.51, True], True], ['partial repair probe 2', [15.05, 105.0, 90.0, 0.060000000000000005, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [21.0, 120.0, 100.0, 0.25, False], False], ['normal control 2', [6.0, 105.0, 100.0, 0.25, True], False], ['normal control 3', [6.5, 105.0, 100.0, 0.5, False], False]], [['regression extrinsic measure 1', [6.5, 105.0, 100.0, 1.51, True], True], ['regression extrinsic measure 2', [11.0, 100.0, 90.0, 1.01, True], True], ['partial repair probe 1', [10.05, 100.0, 90.0, 1.0, True], True], ['partial repair probe 2', [9.0, 98.0, 90.0, 1.01, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [30.25, 120.0, 90.0, 0.25, True], False], ['normal control 2', [1.5, 98.0, 100.0, 1.51, True], False], ['normal control 3', [1.0, 105.0, 110.0, 1.0, True], False]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression extrinsic measure 1FalseTrueFailed
regression extrinsic measure 2FalseTrueFailed
partial repair probe 1FalseTrueFailed
partial repair probe 2FalseTrueFailed
boundary control 1FalseFalsePassed
normal control 1FalseFalsePassed
normal control 2FalseFalsePassed
normal control 3FalseFalsePassed

SHA-256 / 284ff3a869ee163b003123b5ca81ab3e3d66489c7198b39ce1163e2f5398496f

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(call_price, S, K, dividend, last_cum_day):
    c = round(call_price * 100)
    intrinsic = max(round(S * 100) - round(K * 100), 0)
    if not last_cum_day or intrinsic == 0:
        return False
    extrinsic = c - intrinsic
    return round(dividend * 100) > extrinsic
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression extrinsic measure 1', [15.25, 105.0, 90.0, 1.0, True], True], ['regression extrinsic measure 2', [9.5, 98.0, 90.0, 1.51, True], True], ['partial repair probe 1', [8.5, 98.0, 90.0, 0.51, True], True], ['partial repair probe 2', [5.05, 105.0, 100.0, 0.25, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [9.0, 98.0, 90.0, 1.0, False], False], ['normal control 2', [1.0, 98.0, 100.0, 1.0, True], False], ['normal control 3', [0.25, 105.0, 110.0, 0.25, True], False]], [['regression extrinsic measure 1', [8.25, 98.0, 90.0, 1.0, True], True], ['regression extrinsic measure 2', [31.5, 120.0, 90.0, 1.51, True], True], ['partial repair probe 1', [30.05, 120.0, 90.0, 1.0, True], True], ['partial repair probe 2', [10.05, 100.0, 90.0, 0.25, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [0.25, 98.0, 100.0, 1.0, True], False], ['normal control 2', [1.5, 100.0, 100.0, 1.5, True], False], ['normal control 3', [8.5, 98.0, 90.0, 0.5, False], False]], [['regression extrinsic measure 1', [9.5, 98.0, 90.0, 1.51, True], True], ['regression extrinsic measure 2', [5.25, 105.0, 100.0, 0.26, True], True], ['partial repair probe 1', [10.25, 100.0, 90.0, 1.0, True], True], ['partial repair probe 2', [15.05, 105.0, 90.0, 0.060000000000000005, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [0.05, 98.0, 110.0, 0.5, True], False], ['normal control 2', [1.0, 100.0, 100.0, 1.0, True], False], ['normal control 3', [15.5, 105.0, 90.0, 0.5, True], False]], [['regression extrinsic measure 1', [15.05, 105.0, 90.0, 0.25, True], True], ['regression extrinsic measure 2', [30.05, 120.0, 90.0, 1.0, True], True], ['partial repair probe 1', [16.5, 105.0, 90.0, 1.51, True], True], ['partial repair probe 2', [15.05, 105.0, 90.0, 0.060000000000000005, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [21.0, 120.0, 100.0, 0.25, False], False], ['normal control 2', [6.0, 105.0, 100.0, 0.25, True], False], ['normal control 3', [6.5, 105.0, 100.0, 0.5, False], False]], [['regression extrinsic measure 1', [6.5, 105.0, 100.0, 1.51, True], True], ['regression extrinsic measure 2', [11.0, 100.0, 90.0, 1.01, True], True], ['partial repair probe 1', [10.05, 100.0, 90.0, 1.0, True], True], ['partial repair probe 2', [9.0, 98.0, 90.0, 1.01, True], True], ['boundary control 1', [10.5, 110.0, 100.0, 0.5, True], False], ['normal control 1', [30.25, 120.0, 90.0, 0.25, True], False], ['normal control 2', [1.5, 98.0, 100.0, 1.51, True], False], ['normal control 3', [1.0, 105.0, 110.0, 1.0, True], False]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression extrinsic measure 1TrueTruePassed
regression extrinsic measure 2TrueTruePassed
partial repair probe 1TrueTruePassed
partial repair probe 2TrueTruePassed
boundary control 1FalseFalsePassed
normal control 1FalseFalsePassed
normal control 2FalseFalsePassed
normal control 3FalseFalsePassed

SHA-256 / 87d21d2d74255098782d1ae196b3a5ec27f2ba31064ff5fbea03d20a16313fd9

Verification & scope

A deterministic toy contract stated explicitly in the contract field; no claim of conformance to any exchange or clearing rulebook. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:46:58.420751+00:00.

Case digest / b8ce0a7e0e9c0142d68e66921859ae800009fea7e262ef1c031c5590a95f9b60