Apply New York's rules for a filer who can be claimed as a dependent

[MaxGhenis]

Summary

New York Tax Law 606, 616 and 1310 bar an individual whom another taxpayer can claim from several credits and from dependent exemptions; the model did not apply them consistently (the 2026 child and dependent care credit barred only a claimable filer labelled head; the rest were not applied). Form IT-201 asks once per return, at item C, "Can you be claimed as a dependent on another taxpayer's federal return?", and the household credit instructions say "If you marked the Yes box at item C ... you do not qualify". Some provisions instead work per spouse.

Stacked on the federal claimable-filer PR (whose CTC, child care and EITC changes flow into New York's 2021-2024 Empire State child credit, child care credit and EITC) and on #10024.

Formula	Rule now	Source
ny_household_credit_potential	$0 when either filer can be claimed	Tax Law 606(b); IT-201 line 40
nyc_household_credit	Same	Tax Law 1310(d); IT-201 line 48
nyc_school_tax_credit_fixed_amount(_eligible)	Needs a filer who cannot be claimed; a joint return on which one spouse can be claimed gets the individual $63	Tax Law 606(ggg)(4-a); Form NYC-210 instructions: "credit amount of the eligible spouse"
nyc_school_tax_credit_rate_reduction_amount_eligible	Needs a filer who cannot be claimed	606(ggg)(4-b); IT-201 line 69a
ny_real_property_tax_credit	Needs a filer who cannot be claimed. On a return that cannot claim dependents, a dependent's age no longer reaches the elderly table	606(e)(7)(E); 606(e)(6)(C) covers "a qualified taxpayer and their spouse"; IT-214: "You could not be claimed as a dependent"
ny_exemptions (and its copies in the dependent exemption and working families tax credit reforms)	No dependent exemptions when either filer can be claimed and the filing exception does not apply	Tax Law 616(a) (a dependent for whom the taxpayer is entitled to an IRC 151(c) deduction); IRC 152(b)(1)
ny_allowable_college_tuition_expenses	Leaves out a student who is claimed on another return (an actual-claim rule), and a return's dependents when a filer can be claimed and the filing exception does not apply	606(t)(2)(D); IT-272: "only the person who claims the student as a dependent"; 616(a) with IRC 152(b)(1) for the dependents
nyc_cdcc_age_restricted_expenses	No under-4 dependents when either filer can be claimed and the filing exception does not apply	NYC Admin Code 11-1706(e)(1): children "who are dependents of the taxpayer"
ny_inflation_refund_credit (2023 base year)	$0 when either filer was claimed (an actual-claim rule)	606(qqq): recipients, including "taxpayers filing joint returns", "must not have been claimed as a dependent"
ny_cdcc (2026 credit under 606(c-2))	$0 when either filer can be claimed; before, only a claimable filer labelled head barred it	606(c-2), added by L.2026 ch. 59, Part A: the taxpayer "is not a dependent of another taxpayer"; a joint return's under-13 children also fail IRC 21(b)(1)(A) with 152(b)(1)
nyc_income_tax_elimination_credit_eligible (2025+)	Not eligible when either filer can be claimed and the filing exception does not apply	Tax Law 1310(h)(1)(A): a dependent for whom the taxpayer is allowed an IRC 151(c) deduction; 152(b)(1); IT-270-I p.1: "you claimed one or more dependents"

Readings for Max (queue via the US + core hub)

1. Household credits on a joint return with one claimable spouse. This PR treats item C as marked when either spouse can be claimed ($0). Tax Law 606(b) lists married couples separately from the unmarried-individual exclusion, so an exemption-count reading ($60 state / $30 NYC in the test household) or a whole-household reading ($75 / $60) is also defensible.

2. School tax rate reduction, one claimable spouse. Kept with the joint schedule; an either-spouse bar or halving are the alternatives. The fixed amount follows Form NYC-210's per-spouse rule.

3. Real property tax credit, one claimable spouse. Kept (606(e)(6)(C)); an either-spouse bar from IT-214's single question is the alternative.

4. 2026 child and dependent care credit, one claimable spouse. This PR bars the joint return (a joint return is one taxpayer). 606(c-2)(2)(B) defines its own qualifying individuals and includes an incapacitated spouse, so a per-spouse reading could let the spouse who cannot be claimed keep the credit for an incapacitated spouse. No 2026 IT-216 instructions exist yet to settle it.

5. New York City child care credit, incapacitated child under 4 of a claimable filer. This PR reads NYC Admin Code 11-1706(e)(1)'s "dependents of the taxpayer" literally, so the child's expenses do not count ($0). Reading dependency through the incorporated IRC 21 definition, which keeps an incapacitated dependent, would count them ($288.75 in a household with $1,000 of expenses and a $385 state credit).

6. College tuition on a joint return with one claimed spouse. This PR keeps the other spouse's own tuition ($6,000 of allowable expenses and a $240 credit in the test household), reading 606(t)(2)(D) per individual. Form IT-272 asks one dependency question for the return and stops there, which would give $0.

Which fact each rule reads

#10024 separates three facts. Own college tuition and the inflation refund read whether a filer is claimed. The household credits, school tax credits, real property tax credit and 2026 child and dependent care credit read whether a filer can be claimed. The rules that need dependents (dependent exemptions and both reforms, dependents' tuition, under-4 care expenses, the elimination credit's dependent test) read whether a filer can be claimed and the filing exception does not apply (Pub. 501).

Known limits of the inputs

• Which return claims the student. IT-272 bars a student "claimed as a dependent on another person's New York State tax return". The model has no input for which return claims a person, so a claimed student is taken to be claimed on a New York return. A New York student claimed only on an out-of-state parent's federal return would keep the tuition credit or deduction ($6,000 of allowable expenses in the test household) and gets $0 here.

Invariants

1. Swap invariance of every changed output under either head/spouse labelling.
2. Monotonicity. Marking another filer as claimed never raises any changed output.
3. Unchanged when no filer can be claimed or is claimed (a filer who can be claimed but is not claimed triggers the "can be claimed" rules).

Tests

• YAML: variable-named cases for every changed formula. Each joint case with a claimable spouse appears under both head/spouse labellings, except the one filing-exception control for the real property tax credit. Run locally at edd12b8407: the changed YAML files and the test folders next to every changed variable (58 files): 542 passed, 0 failed.
• Property test policyengine_us/tests/core/test_claimable_filer_ny_invariants.py for 2023, 2025 and 2026 (state-level outputs). Hypothesis batches check invariant 1; a seeded population and crafted couples with tuition (their own and a dependent student's) check 1 and 2. The New York City credits need a New York City household and, like the reforms, are covered by YAML only. Invariant 3 is checked by the microsimulation below, where no filer is claimed. 4 tests passed, 0 failed, in 36 s with a peak memory footprint of 1.8 GB (/usr/bin/time -l).

Microsimulation impact

Real microsimulations on the default dataset (hf://datasets/policyengine/populace-us/populace_us_2024.h5@populace-us-2024-spm-20260909) for 2025 and 2026, compared record by record. In that dataset no person can be claimed as a dependent on another return (claimable_as_dependent_on_another_return is true for 0 of 166,321 people), so every rule gated on it is inactive there; the runs check that nothing else moves.

This stack's federal branch (35a2cbcbb9) against a local merge of the four state branches onto it (13d24ac157). Each state branch changes only its own state's variables, so the comparison is split by state.

• 2025: no record changes in this PR's states.
• 2026: no record changes in this PR's states.

Axiom parity

axiom: us-ny/statutes/TAX/606(b) queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/1310(d) + us-ny/statutes/NYC/11-1706(b) queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/606(ggg)(4-a) queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/606(ggg)(4-b) + us-ny/policies/tax/it-201-instructions/nyc-school-tax-credit-rate-reduction queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/606(e) queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/616 queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/606(t)(2)(D) queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/606(qqq) queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/NYC/11-1706(e)(1) + us-ny/policies/tax/it-216-instructions/nyc-child-dependent-care-credit queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/606(c-2) queued (NY1: TheAxiomFoundation/rulespec-us#1688) | us-ny/statutes/TAX/1310(h) queued (NY1: TheAxiomFoundation/rulespec-us#1688)

Every queued item is a pe-parity issue filed in TheAxiomFoundation/rulespec-us on 2026-10-12 (verbatim law, required outputs, review finding, companion tests).

🤖 Generated with Claude Code

[MaxGhenis]

Hand-off to the US + core hub

• Head: edd12b8407
• Independent review: APPROVE at 6076b2dca6 (GPT-6.1 Sol, round 3). The current head only merges the reviewed federal head 35a2cbcbb9 into it; this PR's own diff is byte-identical to the reviewed one. Verdict file: ~/reviews/us-hub/claimable-filer-rules/reviews/r3/out-ny.md.
• Passed locally: 58 YAML files: 542 passed, 0 failed; property test 4 passed. Also: a sweep of every YAML file in the repo that sets a dependent-elsewhere input (115 files) on a merge of all five branches, 0 failed; microsimulations for 2025 and 2026 (details in the PR body).
• Depends on: Apply the federal rules for a filer who can be claimed as a dependent #10087 and Make rules for a filer claimed elsewhere independent of which spouse is labelled head #10024.

Pending (not mine to do):

• Merge order: this stack lands after Make rules for a filer claimed elsewhere independent of which spouse is labelled head #10024 (approved at c7f969f872, on the hub's CI queue), then Apply the federal rules for a filer who can be claimed as a dependent #10087 (federal), then the four state PRs. CI does not run on PRs whose base is not main, so each needs a CI run after it is retargeted to main and marked ready.
• Readings for Max are listed in the PR body under "Readings for Max" for the hub to queue (none queued by me).
• Axiom parity: the axiom: line marks each provision needed (draft, held for Max); filing the eleven drafted rulespec-us issues is decision d1341 (drafts in ~/reviews/us-hub/claimable-filer-rules/axiom/drafts/).

Follow-ups: listed in #10087 under "Follow-ups"; the hub holds the regional state PRs stacked on the federal branch.

Session local_0143a3e8-4ab1-4492-8aab-9140b74e67e5 is closing; the hub owns this PR from here.