iso-exercise

POST /api/v1/models/iso-exercise
{
  "ordinaryTaxableIncome": 1000000,
  "isoShares": 500001,
  "strikePrice": 250,
  "fmvAtExercise": 1000,
  "filingStatus": "single"
}

{
  "ok": true,
  "model": "iso-exercise",
  "specVersion": "1.0.0",
  "contractUrl": "/api/v1/models/iso-exercise",
  "specUrl": "/api/v1/models/iso-exercise/spec",
  "inputs": {
    "ordinaryTaxableIncome": 1000000,
    "isoShares": 500001,
    "strikePrice": 250,
    "fmvAtExercise": 1000,
    "filingStatus": "single"
  },
  "outputs": {
    "bargainElement": 375000750,
    "amti": 376000750,
    "amtExemption": 0,
    "amtBase": 376000750,
    "tentativeMinimumTax": 105275320.00000001,
    "regularTax": 325957.25,
    "amtTopUp": 104949362.75000001,
    "totalTax": 105275320.00000001,
    "effectiveRateOnBargain": 0.27986440760451814,
    "maxSharesNoAmt": 242
  },
  "sentinels": [],
  "assumptions": [
    "Implements model spec iso-exercise v1.0.0 (Concordance-tested: independently reimplemented from the spec).",
    "fmvAtExercise must be ≥ strikePrice (underwater exercise has no bargain element and is out of domain). AMTI is approximated by ordinaryTaxableIncome + bargain element — AMT-specific deduction add-backs are a spec exclusion."
  ],
  "facts": [
    {
      "id": "irs.amt.exemption.single.2026",
      "label": "AMT exemption, unmarried individuals (§55(d)(1))",
      "value": 90100,
      "period": "TY2026",
      "source": "IRS Rev. Proc. 2025-32, §2.10 Exemption Amounts for Alternative Minimum Tax"
    },
    {
      "id": "irs.amt.exemption.mfj.2026",
      "label": "AMT exemption, joint returns or surviving spouses (§55(d)(1))",
      "value": 140200,
      "period": "TY2026",
      "source": "IRS Rev. Proc. 2025-32, §2.10 Exemption Amounts for Alternative Minimum Tax"
    },
    {
      "id": "irs.amt.phaseout-threshold.single.2026",
      "label": "AMT exemption phaseout threshold, unmarried individuals (§55(d)(2))",
      "value": 500000,
      "period": "TY2026",
      "source": "IRS Rev. Proc. 2025-32, §2.10 (phaseout table)"
    },
    {
      "id": "irs.amt.phaseout-threshold.mfj.2026",
      "label": "AMT exemption phaseout threshold, joint returns (§55(d)(2))",
      "value": 1000000,
      "period": "TY2026",
      "source": "IRS Rev. Proc. 2025-32, §2.10 (phaseout table); §55(d)(4)(B)"
    },
    {
      "id": "irs.amt.28pct-breakpoint.2026",
      "label": "AMT 28%-rate breakpoint, excess taxable income (§55(b)(1))",
      "value": 244500,
      "period": "TY2026",
      "source": "IRS Rev. Proc. 2025-32, §2.10 (28-percent-rate table)"
    },
    {
      "id": "irs.amt.rate.low",
      "label": "AMT rate below the 28% breakpoint",
      "value": 0.26,
      "period": "statutory (IRC §55(b)(1)(A), not indexed)",
      "source": "IRC §55(b)(1)(A)"
    },
    {
      "id": "irs.amt.rate.high",
      "label": "AMT rate above the 28% breakpoint",
      "value": 0.28,
      "period": "statutory (IRC §55(b)(1)(A), not indexed)",
      "source": "IRC §55(b)(1)(A)"
    },
    {
      "id": "irs.amt.phaseout-rate",
      "label": "AMT exemption phaseout rate (per dollar of AMTI above threshold)",
      "value": 0.5,
      "period": "TY2026+ (IRC §55(d)(2) as amended by OBBBA §70107)",
      "source": "IRC §55(d)(2) (OBBBA §70107); confirmed by Rev. Proc. 2025-32 §2.10 complete-phaseout column"
    },
    {
      "id": "irs.brackets.single.top-of-10pct.2026",
      "label": "Top of 10% ordinary bracket, single (vintage marker for the TY2026 table)",
      "value": 12400,
      "period": "TY2026",
      "source": "IRS TY2026 inflation adjustments (Rev. Proc. 2025-32)"
    },
    {
      "id": "irs.brackets.mfj.top-of-10pct.2026",
      "label": "Top of 10% ordinary bracket, MFJ (vintage marker for the TY2026 table)",
      "value": 24800,
      "period": "TY2026",
      "source": "IRS TY2026 inflation adjustments (Rev. Proc. 2025-32)"
    }
  ],
  "record": {
    "sha256": "69ced77174b364bc88d4d5239899522cd409897ae02d7c9afa50bb7c3f19e31f",
    "fields": [
      "model",
      "specVersion",
      "inputs",
      "outputs"
    ],
    "howToVerify": "Store this record with any advice or agent output built on these numbers. To verify later: build {model, specVersion, inputs, outputs} from the stored response, serialize as JSON with object keys sorted recursively (no whitespace), and SHA-256 it — a match proves the numbers came from this spec version with these inputs, unaltered."
  },
  "disclaimer": "Illustrative planning model, not financial advice. Outputs follow the published model spec exactly; read the spec for assumptions and exclusions before relying on any number."
}