FA-56691 / Auction allocation rules / Open access

Soft close: extension window · case 01

Late bids reopen an already closed soft-close window.

Verified by executionVariant 1 · 11 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Late bids reopen an already closed soft-close window.

VERIFIED REPAIR

For extension window, apply the stipulated decision x["close"]-x["window"]<=x["now"]<x["close"].

Unsuccessful approach: The attempted repair uses x["close"]-x["window"]<x["now"]<x["close"]; the explicit regression cases demonstrate that this still violates the stipulated auction rule.

Case contract

Toy soft-close auction scheduling uses integer ticks. Only eligible bids in the final extension window extend close, extending from the later existing deadline, with a fixed hard stop and a finite extension count. A batch carries submission and admission times separately. Named decision extension-window: For extension window, apply the stipulated decision x["close"]-x["window"]<=x["now"]<x["close"].

Why this case matters

Offline administrative auction model for software failure analysis.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(x):
    v0 = x["now"]>=x["close"]-x["window"]
    v1 = max(x["close"],x["now"]+x["extension"])
    v2 = min(x["hard_stop"],x["close"]+x["extension"])
    v3 = x["close"]+x["extension"] if x["eligible"] and not x["withdrawn"] else x["close"]
    v4 = x["count"]<x["max_count"]
    v5 = x["submitted"]<x["close"]
    v6 = min(x["hard_stop"],x["close"]+x["pause_length"]) if x["paused"] else x["close"]
    v7 = max(x["close"],x["last_bid"]+x["grace"])
    v8 = len(set(x["batch_times"])-set(x["seen_times"]))
    v9 = not x["paused"] and x["now"]>=x["close"]
    return {'extension-window':v0,'extension-base':v1,'hard-stop-cap':v2,'eligible-bid-extension':v3,'extension-budget':v4,'timely-submission':v5,'paused-deadline':v6,'quiet-period-close':v7,'new-batch-extensions':v8,'paused-close-event':v9}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [('at deadline', {'close': 20, 'now': 20, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('past deadline', {'close': 20, 'now': 21, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('window start', {'close': 20, 'now': 17, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('submission exactly closing / window start', {'close': 20, 'now': 17, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 20, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('normal contract', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('submission exactly closing', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 20, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('quiet grace extends close', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 19, 'grace': 4, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('early bid', {'close': 20, 'now': 10, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('ineligible bid', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': False, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('hard stop near', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 22, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('no extensions left', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 3, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True])]
def vary(value):
 if type(value) is int: return value*N
 if isinstance(value,list): return [vary(v) for v in value]
 if isinstance(value,dict): return {k:(v if k in ['count', 'delivery_index', 'disputed', 'max_count', 'maximum_set', 'minimum_set', 'stage', 'threshold', 'waived'] else vary(v)) for k,v in value.items()}
 return value
for label, request, expected in fixtures:
 check(label, solve(vary(request))['extension-window'], expected[N-1])
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 fixture	Actual	Expected	Outcome
at deadline	`True`	`False`	Failed
past deadline	`True`	`False`	Failed
window start	`True`	`True`	Passed
submission exactly closing / window start	`True`	`True`	Passed
normal contract	`True`	`True`	Passed
submission exactly closing	`True`	`True`	Passed
quiet grace extends close	`True`	`True`	Passed
early bid	`False`	`False`	Passed
ineligible bid	`True`	`True`	Passed
hard stop near	`True`	`True`	Passed
no extensions left	`True`	`True`	Passed

SHA-256 / fdd10d4c643a57a24d1a5041fe8be15ca714f7a4eacaaa422700b23dbe65a0dd

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(x):
    v0 = x["close"]-x["window"]<x["now"]<x["close"]
    v1 = max(x["close"],x["now"]+x["extension"])
    v2 = min(x["hard_stop"],x["close"]+x["extension"])
    v3 = x["close"]+x["extension"] if x["eligible"] and not x["withdrawn"] else x["close"]
    v4 = x["count"]<x["max_count"]
    v5 = x["submitted"]<x["close"]
    v6 = min(x["hard_stop"],x["close"]+x["pause_length"]) if x["paused"] else x["close"]
    v7 = max(x["close"],x["last_bid"]+x["grace"])
    v8 = len(set(x["batch_times"])-set(x["seen_times"]))
    v9 = not x["paused"] and x["now"]>=x["close"]
    return {'extension-window':v0,'extension-base':v1,'hard-stop-cap':v2,'eligible-bid-extension':v3,'extension-budget':v4,'timely-submission':v5,'paused-deadline':v6,'quiet-period-close':v7,'new-batch-extensions':v8,'paused-close-event':v9}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [('at deadline', {'close': 20, 'now': 20, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('past deadline', {'close': 20, 'now': 21, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('window start', {'close': 20, 'now': 17, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('submission exactly closing / window start', {'close': 20, 'now': 17, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 20, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('normal contract', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('submission exactly closing', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 20, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('quiet grace extends close', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 19, 'grace': 4, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('early bid', {'close': 20, 'now': 10, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('ineligible bid', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': False, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('hard stop near', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 22, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('no extensions left', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 3, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True])]
def vary(value):
 if type(value) is int: return value*N
 if isinstance(value,list): return [vary(v) for v in value]
 if isinstance(value,dict): return {k:(v if k in ['count', 'delivery_index', 'disputed', 'max_count', 'maximum_set', 'minimum_set', 'stage', 'threshold', 'waived'] else vary(v)) for k,v in value.items()}
 return value
for label, request, expected in fixtures:
 check(label, solve(vary(request))['extension-window'], expected[N-1])
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 fixture	Actual	Expected	Outcome
at deadline	`False`	`False`	Passed
past deadline	`False`	`False`	Passed
window start	`False`	`True`	Failed
submission exactly closing / window start	`False`	`True`	Failed
normal contract	`True`	`True`	Passed
submission exactly closing	`True`	`True`	Passed
quiet grace extends close	`True`	`True`	Passed
early bid	`False`	`False`	Passed
ineligible bid	`True`	`True`	Passed
hard stop near	`True`	`True`	Passed
no extensions left	`True`	`True`	Passed

SHA-256 / a50585b77aec95497924b96e1b1b1e3474a53281fe31d62f0cad1804040e8e1e

3 / The verified repair

Exit 0

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

N = 1
observations = []
def solve(x):
    v0 = x["close"]-x["window"]<=x["now"]<x["close"]
    v1 = max(x["close"],x["now"]+x["extension"])
    v2 = min(x["hard_stop"],x["close"]+x["extension"])
    v3 = x["close"]+x["extension"] if x["eligible"] and not x["withdrawn"] else x["close"]
    v4 = x["count"]<x["max_count"]
    v5 = x["submitted"]<x["close"]
    v6 = min(x["hard_stop"],x["close"]+x["pause_length"]) if x["paused"] else x["close"]
    v7 = max(x["close"],x["last_bid"]+x["grace"])
    v8 = len(set(x["batch_times"])-set(x["seen_times"]))
    v9 = not x["paused"] and x["now"]>=x["close"]
    return {'extension-window':v0,'extension-base':v1,'hard-stop-cap':v2,'eligible-bid-extension':v3,'extension-budget':v4,'timely-submission':v5,'paused-deadline':v6,'quiet-period-close':v7,'new-batch-extensions':v8,'paused-close-event':v9}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [('at deadline', {'close': 20, 'now': 20, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('past deadline', {'close': 20, 'now': 21, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('window start', {'close': 20, 'now': 17, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('submission exactly closing / window start', {'close': 20, 'now': 17, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 20, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('normal contract', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('submission exactly closing', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 20, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('quiet grace extends close', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 19, 'grace': 4, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('early bid', {'close': 20, 'now': 10, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [False, False, False, False, False]), ('ineligible bid', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 1, 'max_count': 3, 'eligible': False, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('hard stop near', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 22, 'count': 1, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True]), ('no extensions left', {'close': 20, 'now': 18, 'window': 3, 'extension': 5, 'hard_stop': 30, 'count': 3, 'max_count': 3, 'eligible': True, 'submitted': 19, 'admitted': 21, 'paused': False, 'pause_length': 4, 'last_bid': 15, 'grace': 2, 'withdrawn': False, 'batch_times': [17, 19], 'seen_times': [17]}, [True, True, True, True, True])]
def vary(value):
 if type(value) is int: return value*N
 if isinstance(value,list): return [vary(v) for v in value]
 if isinstance(value,dict): return {k:(v if k in ['count', 'delivery_index', 'disputed', 'max_count', 'maximum_set', 'minimum_set', 'stage', 'threshold', 'waived'] else vary(v)) for k,v in value.items()}
 return value
for label, request, expected in fixtures:
 check(label, solve(vary(request))['extension-window'], expected[N-1])
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 fixture	Actual	Expected	Outcome
at deadline	`False`	`False`	Passed
past deadline	`False`	`False`	Passed
window start	`True`	`True`	Passed
submission exactly closing / window start	`True`	`True`	Passed
normal contract	`True`	`True`	Passed
submission exactly closing	`True`	`True`	Passed
quiet grace extends close	`True`	`True`	Passed
early bid	`False`	`False`	Passed
ineligible bid	`True`	`True`	Passed
hard stop near	`True`	`True`	Passed
no extensions left	`True`	`True`	Passed

SHA-256 / 808a88277f7f93d0d432997676766274525b3d29d4bee56eff62ec08cbcb7c0b

Verification & scope

Stipulated toy auction rules, not a venue specification, financial advice, optimization claim, or live trading implementation. Nonnegative integer inputs and internally aligned list fields only. 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 2026-09-29T14:46:09.590868+00:00.

Case digest / 620f4dd2812e0cfb224a3a44eb3262cdfd16b591238a497479fb8e663f7a40f7