PFIC Mark-to-Market Election: §1296 MTM Gains, Losses, UNI and Cost Basis

This guide covers the eligibility criteria and calculation mechanics of the §1296 Mark-to-Market election: marketable stock qualification under Treas. Reg. §1.1296-2, unrealized gain/loss computation, basis adjustments, Unreversed Inclusions tracking, and Form 8621 Part IV mapping. Not sure if MTM applies to your situation? See the PFIC method selection guide (§1291 vs MTM vs QEF).

Who Can Make a §1296 MTM Election? (Marketable Stock Rules)

Under Treas. Reg. §1.1296-2, a U.S. shareholder may make a Section 1296 election only if the PFIC stock qualifies as "marketable stock." To qualify, the stock must satisfy either of the two statutory pathways below. Note that within whichever pathway is relied upon, all mandatory criteria are cumulative and strictly non-negotiable (all conditions must be met concurrently):

Core Calculation Mechanism of the PFIC MTM Election

The MTM regime compares Year-End Fair Market Value (FMV) with the Adjusted Cost Basis. Rather than simulating a "sell and repurchase," the mechanism relies on annual basis adjustments:

• Year-End FMV > Adjusted Basis: The excess is recognized as Ordinary Income.
• Year-End FMV < Adjusted Basis: An Ordinary Loss deduction is allowed (capped at "Unreversed Inclusions").

Statutory Text (§1296(a)):

Standard §1296 MTM Annual Calculation Algorithm

Complete MTM Calculation Flow (Held for Entire Tax Year)

Handling PFIC Buys and Sells During the MTM Tax Year

When transactions occur mid-year, the calculation is segmented:

• Purchasing New Stock: Record the actual acquisition price and date. At year-end, calculate the MTM delta based on the FMV on Dec 31 vs. the purchase cost. Treated as an independent lot per Reg. §1.1296-1(c)(5) and §1.1012-1.
• Selling Stock:
  • Realized Gain/Loss = Sale Price - Adjusted Basis on the date of sale (not year-end FMV).
  • Realized Gain: Recognized entirely as Ordinary Income. (§1296(c)(1)(A))
  • Realized Loss: Treated as an ordinary loss up to the available Unreversed Inclusions limit. Any excess loss beyond UNI is treated under standard capital loss rules.
• Retained Shares: The remaining unsold shares proceed through the standard year-end MTM algorithm.

PFIC Lot-Level Maintenance Requirements Under MTM

Regulatory Basis: Reg. §1.1296-1(c)(5)

Using a "Global Average Cost" is technically incorrect for PFIC MTM. The regulations mandate that lots with different cost bases be tracked independently per §1.1012-1. This strictly prohibits Global Pooling across lots for UI calculation.

Required Lot-Level Fields for MTM Calculation Engines

Minimum Required Columns for Annual Maintenance:
├── Txn ID: Lot tracking ID.
├── Date: Event date.
├── Type: Event type.
├── MTM Opening USD: Prior year ending basis.
├── MTM Opening Units: Start-of-year units.
├── ID Unit Basis: Adjusted unit cost.
├── Unreversed Inclusions: Cumulative UNI buffer.
├── Units Sold: Shares sold.
├── Sold Amount (13a): Total sale proceeds.
├── Basis Consumed (13b): Cost of shares sold.
├── Realized Gain USD: Realized cash gain.
├── Units Balance: Remaining share count.
├── FMV (10a): EOY market value.
├── Ordinary Recapture USD: Recaptured ordinary income.
├── Ordinary Loss Applied (14b): Realized loss limited by UNI.
├── UMII mid: (UNI After Sale) Post-sale UNI balance.
├── Other Loss USD (14c): Loss remaining after the ordinary-loss limit.
├── Remaining Basis (10b): MTM Opening USD − Basis Consumed.
├── MTM Gain/Loss (10c): FMV (10a) − Remaining Basis (10b).
├── Allowed Loss USD (12): min(MTM Loss, Unreversed Inclusions).
├── Ordinary Income: Taxable mark-to-market gain.
├── Adjusted Basis (EOY): EOY adjusted basis.
└── Unreversed Inclusions (EOY): EOY UNI balance.

PFIC Lot Identification Methods (§1.1012-1(c))

• Specific Identification: Must be supported and align with §1.1012-1(c) requirements where the taxpayer explicitly identifies which lot is being sold.
• FIFO (First-In, First-Out): Default assumption if specific identification is not provided.
• LIFO Prohibited: §1.1012-1 does not authorize LIFO as a standalone stock identification rule. To mitigate tax audit risk, LIFO should not be an available preset.

Unreversed Inclusions (UNI) Calculation Rules for PFICs

Regulatory Basis: §1296(d); Reg. §1.1296-1(a)(3)

Definition of Unreversed Inclusions (UNI)

CRITICAL: The UI balance can never drop below zero. There is no such thing as negative UI.

Purpose of Unreversed Inclusions (UNI) in MTM

• Acts as a strict ceiling on the amount of MTM loss that can be deducted in a given year: Maximum Deduction = MIN(Current Year Loss, UI).
• Upon sale, any realized loss exceeding the UI balance is treated as a capital loss, not an ordinary loss.
• UI is strictly a lot-specific metric. A loss in Lot A cannot be offset by UI generated from Lot B.

UNI Treatment Under §1291 MTM Coordination Rules

When the first year of MTM election triggers the §1291 coordination rule (see Section 15), the gain amount treated as an excess distribution under §1291 is added to the initial UI balance (excluding the interest charge portion), allowing it to buffer future MTM losses. (Reg. §1.1296-1(a)(3)(ii))

Ordinary Loss Deduction Rules for §1296 MTM

Regulatory Basis: §1296(a)(2), §1296(c)(1)(B); Reg. §1.1296-1(c)(3)(4)

Annual PFIC MTM Loss Deduction Limits

Annual Allowed MTM Deduction = MIN(Year-End Paper Loss, Unreversed Inclusions)

• The allowed deduction is characterized as an Ordinary Loss (§1296(c)(1)(B)), which can offset Adjusted Gross Income (AGI).
• Any excess loss beyond UI is not deductible in the current year. It does not carry forward as an attribute; instead, the cost basis simply remains unadjusted by that excess amount.

PFIC Capital & Ordinary Loss Treatment on Sale

When a PFIC position is liquidated at a loss:

PFIC Distributions & Dividend Treatment Under MTM

Regulatory Basis: §1296(j); Reg. §1.1296-1(i); Form 8621 Instructions

PFIC Distributions During Active MTM Years

Scenario 1: Pure MTM Year (No §1291 Taint)

• Distributions are exempt from the punitive §1291 excess distribution rules.
• Taxable distributions are generally governed by normal U.S. corporate distribution rules (§301). However, dividends from a corporation treated as a PFIC for the current or preceding taxable year do not qualify as Qualified Dividend Income (QDI) under IRC §1(h)(11)(C)(iii) (see IRS Notice 2004-70). MTM ordinary inclusions are likewise not QDI.
• Distributions do not trigger immediate basis adjustments (MTM handles value changes at year-end).

Scenario 2: First-Year MTM with §1291 Taint (Coordination Year)

• If the coordination rule applies, any distributions received during that first transition year remain subject to §1291 excess distribution rules. (§1296(j)(1)(A); Reg. §1.1296-1(i)(2)(i))

Dividend Impact on MTM Adjusted Cost Basis

Under MTM, the annual inclusion/deduction process inherently captures value fluctuations. Therefore, the receipt of an ordinary dividend does NOT reduce the MTM cost basis. The basis is only adjusted via the annual MTM inclusion or allowed MTM deduction.

Adjusted Cost Basis Rules for PFIC MTM

Regulatory Basis: §1296(b)(1); Reg. §1.1296-1(d)(1)

Direct PFIC Ownership Basis Adjustments

Year-End Adjusted Basis = Beginning Adjusted Basis + Current Year MTM Income - Current Year Allowed MTM Deduction.

Indirect PFIC Ownership Basis Adjustments (Pass-Throughs)

When a PFIC is held indirectly through a foreign partnership, foreign trust, or foreign estate:

• The MTM measurement date typically aligns with the tax year-end of the entity, which flows through to the U.S. owner's tax year. (Reg. §1.1296-1(e))
• A dual basis push-up occurs: the MTM inclusion increases both the basis of the PFIC stock inside the entity AND the U.S. person's basis in their partnership/entity interest. This prevents double taxation upon eventual disposition of the entity. (§1296(b)(2); Reg. §1.1296-1(d)(2))

Initial MTM Cost Basis for Newly Acquired Lots

The starting cost basis for newly acquired lots is the actual purchase price (including commissions) in USD. If paid in a foreign currency, it must be translated using the spot rate on the exact date of acquisition.

PFIC Return of Capital (ROC) Distribution Mechanics

Regulatory Basis: §1296(b); Reg. §1.1296-1(d)(1); §301; §316

Return of Capital Under the PFIC MTM Regime

If a distribution is classified as a Return of Capital (§301(c)(2)) rather than a taxable dividend during an MTM-active year:

1. The distribution is generally not included in gross income.
2. It decreases the adjusted cost basis of the stock.
3. If basis is reduced to zero, any distribution in excess of basis is treated as gain from a sale or exchange under §301(c)(3). Any gain recognized under §301(c)(3) requires coordination with the §1296 character rules.

Algorithm Sequence: MTM captures value changes, but if a large ROC distribution occurs, the engine must: (1) Reduce the lot's basis by the ROC amount mid-year. (2) Perform the year-end MTM delta calculation using this newly reduced basis.

Foreign Source of Income Rules for PFIC MTM

Regulatory Basis: IRC §1296(c)(2); Treas. Reg. §1.1296-1(c)(6); IRC §865

Under IRC §1296(c)(2) and Treas. Reg. §1.1296-1(c)(6), any amount included in income under the MTM election, and any allowable deduction, is sourced in the same manner as a gain or loss from the sale of the underlying PFIC stock.

• Under the general sourcing rules of IRC §865(a), gain from the sale of personal property (including corporate stock) by a U.S. resident is generally U.S.-source income, subject to applicable statutory exceptions (such as §865(e) or §865(h) treaty sourcing).
• For taxpayers claiming the Foreign Tax Credit (FTC) on Form 1116, this sourcing rule determines whether MTM ordinary income increases the foreign tax credit limitation in the passive category.

PFIC Holding Period Reset & MTM Termination

Regulatory Basis: Reg. §1.1296-1(f)

If an MTM election is terminated (e.g., via revocation or the stock ceases to be marketable), the holding period for the stock is reset for the purposes of PFIC rules.

• The new holding period is treated as beginning on the first day of the first taxable year following the termination of the MTM election.
• This has profound implications if the stock reverts to the §1291 regime, as the pre-MTM holding period is essentially wiped out.

Full PFIC Liquidation Mid-Year Under MTM

Problem: How is MTM calculated if a taxpayer sells their entire PFIC position before the tax year ends (e.g., in October)?

The treatment strictly depends on whether the MTM election was already active or if this is the first intended year of election.

Scenario A: Election was active in prior years, position liquidated mid-year

• No year-end virtual MTM calculation is performed. Reg. §1.1296-1(c)(2) governs the disposition.
• Realized Gain = Sale Price - Adjusted Basis. Treated entirely as Ordinary Income (§1296(c)(1)(A)).
• Realized Loss is bounded by accumulated UI as Ordinary Loss, remainder as Capital Loss.
• Reported on Form 8621 Part IV Lines 13-14c. Year-end FMV lines are not applicable.

Scenario B: Taxpayer intended to elect MTM for the first time this year, but liquidated early

• This presents a severe eligibility risk. The instructions for Election C and Reg. §1.1296-1(h)(1)(i) generally require the taxpayer to own marketable stock at the close of the taxable year to make a valid initial election.

New U.S. Residents: §1296(l) Transition Basis Step-Up

Problem: An individual becomes a U.S. taxpayer this year, holding a foreign fund acquired years ago. How is the initial basis determined for MTM purposes?

§1296(l) PFIC Basis Step-Up Core Mechanics

• Applicable only to individuals becoming subject to U.S. income tax.
• Only available if the §1296 MTM election is in effect for the individual's first taxable year as a U.S. person.
• Starting Basis (for MTM purposes under §1296) = MAX(FMV on the first day of such taxable year, Adjusted Basis on such first day).
• Dual-Basis Ledger Architecture:
  • MTM Measurement Basis: Initialized to the transition basis under §1296(l) and subsequently increased/decreased by annual MTM inclusions and allowed deductions under Treas. Reg. §1.1296-1(d)(1).
  • General Purpose (§1001) Basis: Starts from the historical adjusted basis, and is also adjusted upward/downward by all §1296 inclusions and allowed deductions recognized while a U.S. person under Treas. Reg. §1.1296-1(d)(1).
  • Eventual Sale Gain Allocation: Upon disposition, total realized gain is measured against the General Purpose basis. The post-residency appreciation recognized via MTM is treated as ordinary income under §1296, while the pre-immigration appreciation is recognized under standard Code provisions (typically as long-term capital gain).
• Authority: IRC §1296(l); Treas. Reg. §1.1296-1(d)(5).

Practical Calculation of the §1296(l) Dual-Basis Rule

Official Framework (Treas. Reg. §1.1296-1(d)(5) Example): Taxpayer becomes a U.S. person on Jan 1, holding 100 shares of a PFIC with historical purchase cost of $10,000 ($100/share). FMV on Jan 1 is $18,000 ($180/share). Timely MTM election is made on the first U.S. return.

• Year 1: FMV on Dec 31 is $20,000 ($200/share).
  • MTM Starting Basis = MAX($18,000, $10,000) = $18,000.
  • Year 1 MTM Inclusion = $20,000 − $18,000 = $2,000 Ordinary Income.
  • Year-End MTM Measurement Basis = $18,000 + $2,000 = $20,000.
  • Year-End General Purpose Basis = $10,000 + $2,000 = $12,000.
• Year 2 Sale: All shares sold on June 30 of Year 2 for $22,000 ($220/share).
  • Total Realized Gain under §1001 = $22,000 − $12,000 (General Basis) = $10,000.
  • Ordinary Income under §1296(c)(1)(A) = $22,000 − $20,000 (MTM Basis) = $2,000.
  • Remaining Gain under General Rules = $10,000 − $2,000 = $8,000 Long-Term Capital Gain (representing the pre-immigration appreciation).

§1296(l) Immigrant Step-Up vs. §1014 Inherited Basis

§1291 Coordination Rule for First-Year MTM Elections After Prior §1291 Years

Regulatory Basis: IRC §1296(j)(1); Treas. Reg. §1.1296-1(i)

Understanding the §1296(j) Coordination Rule

If a taxpayer makes a §1296 MTM election for a taxable year after their holding period in the PFIC stock has begun (and the fund was a non-QEF §1291 fund for one or more prior years), the mandatory §1296(j) coordination rule applies in that first election year.

During this transition year, §1291 continues to apply to:

• Any distributions received during the year (§1296(j)(1)(A); Reg. §1.1296-1(i)(2)(i)).
• Any actual dispositions of the stock during the year.
• The deemed disposition of the stock at year-end, subjecting built-in gain to §1291 tax and interest.

QEF Exception to MTM First-Year Coordination

If the PFIC was a pedigreed Qualified Electing Fund (QEF) for every prior year of the taxpayer's holding period during which the entity was a PFIC, the §1291 taint does not exist, and the coordination rule is bypassed (§1296(j)(1)(B)).

§1296(j) Coordination Transition Workflow for the First Year

1. Identify the trigger: First year of MTM election AND prior non-QEF §1291 PFIC holding period exists.
2. Calculate the §1291 Deemed Disposition Gain:
   • Treat the stock as sold at its Year-End FMV on the last day of the coordination year.
   • Calculate total gain: Year-End FMV − Adjusted Basis.
   • Allocate this gain across the entire holding period under the §1291 excess distribution daily method, triggering highest statutory marginal tax rates and §6621 compounding interest for prior PFIC years.
3. MTM Effects in the Coordination Year:
   • The portion of the deemed gain allocated to the coordination year is treated as current-year ordinary income under §1291(a)(1)(B) (not subject to interest).
   • The entire gain amount subjected to the §1291 rules (excluding the interest charge) is added to the Unreversed Inclusions (UNI) balance under Reg. §1.1296-1(a)(3)(ii).
4. Subsequent Years: From year two onward, the stock operates purely under standard §1296 MTM rules.

CFC Shareholders Holding PFICs: The §1296(f) FPHCI Rule

Regulatory Basis: IRC §1296(f); Treas. Reg. §1.1296-1(g)(2)

When a Controlled Foreign Corporation (CFC) holds PFIC stock and a §1296 MTM election is in effect, §1296(f) establishes special coordination rules with Subpart F:

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Can You Retroactively Elect MTM Under SDOP? Not Through SDOP Alone

Core Principle

The Streamlined Domestic Offshore Procedures (SDOP) allow taxpayers to correct past non-compliance and mitigate penalties. However, SDOP does not grant statutory relief to make late elections, including the §1296 Mark-to-Market (MTM) election.

Legal Authority

Under Treas. Reg. §1.1296-1(h)(1), an MTM election must be made on or before the due date (including extensions) of the tax return for the first taxable year for which the election is to be effective. An amended return filed after the normal election deadline cannot by itself create a late §1296 election, and SDOP does not provide independent administrative election relief.

A late §1296 election may be permitted only through non-automatic relief under Treas. Reg. §301.9100-3, which requires requesting a formal Private Letter Ruling (PLR).

The PLR Reality Check

Section 301.9100-3 relief requires an IRS ruling request. Without relief, prior years keep their original treatment; a later timely MTM election may still be made.

Dual-Status Tax Years for New U.S. Immigrants: The First Day Rule

The year an individual becomes a U.S. tax resident mid-year (e.g., via obtaining a Green Card on August 15 or meeting the Substantial Presence Test) is a Dual-Status Tax Year.

Statutory Anchor: January 1 vs. Green Card Date

Under IRC §1296(l) and Treas. Reg. §1.1296-1(d)(5), the statutory transition starting basis is strictly defined as the greater of FMV or adjusted basis on the "first day of such taxable year" (which is January 1 for calendar-year individual taxpayers), rather than the individual's mid-year immigration or visa-switch date.

Contrast with §1291 Holding Period Rules

While §1296(l) MTM sets its valuation checkpoint on January 1, the default §1291 regime operates differently under Treas. Reg. §1.1291-9(j)(1): for §1291 throwback purposes, a foreign fund is not treated as a PFIC for days before the shareholder became a U.S. person, measuring the holding period precisely from the mid-year residency starting date.

Inherited PFIC Stock Basis Rules Under MTM

Regulatory Basis: Reg. § 1.1296-1(d)(4)

Normally, inherited property receives a full step-up in basis to FMV under §1014. However, if the decedent had a valid MTM election in place for the PFIC, the heir does not automatically receive a full step-up.

• The heir's basis is strictly limited to: MIN(Decedent's adjusted MTM basis immediately before death, FMV on the date of death).
• This prevents heirs from absorbing unrealized MTM gains tax-free. If the stock holds an unrealized loss, the heir inherits the lower FMV. If it holds an unrealized gain since the last MTM checkpoint, the heir is stuck with the lower MTM basis.

Form 8621 Part IV Mapping Guide for §1296 MTM

Form 8621 Part I & Part II Directives for MTM

• Line 1-3: Basic identification and shares held at year-end.
• Line 4: Total FMV of shares held at year-end. Must perfectly match the aggregate amount reported in Part IV Line 10a.
• Line 5 (Excess Distributions): Under standard MTM years, this is $0 or N/A (unless it is a coordination year).
• Part II - Election C: This checkbox is ONLY checked in the first year the MTM election is made. Per §1296(k), it should remain unchecked in all subsequent continuous years.

Form 8621 Part IV Line-by-Line Calculation Mapping

Calculation Rounding Rules for Form 8621 & MTM Engines

• Tax Form Level: Round to the nearest whole dollar on Form 8621.
• Internal Engine Level: Maintain at least 2 decimal places (cents) to prevent cumulative drift.
• Currency Translation: Use 4 to 6 decimal places for spot exchange rates.
• Per-Lot / Per-Share Basis: Maintain 4 to 6 decimal places to ensure aggregate totals remain perfectly balanced during partial dispositions.

Revocation & Termination of the PFIC MTM Election

An MTM election terminates automatically in the following scenarios:

1. The PFIC stock ceases to be marketable stock.
2. The taxpayer is required under another IRC provision (e.g., §475) to mark the stock to market.
3. The IRS Commissioner consents to revocation (requires filing a PLR demonstrating a "substantial change in circumstances").

Upon termination, the holding period is reset to the first day of the first taxable year following termination, and the stock returns to the §1291 regime for future years.

Common Errors & Considerations in PFIC MTM Calculations

Numerical Examples of §1296 MTM Calculations

Scenario A: Standard 3-Year MTM Path (With Loss Cap)

Setup: Taxpayer purchases 100 shares in 2022 at $50/share ($5,000 total). MTM is elected immediately.

Note: In 2024, the paper loss is $700, but UI is only $500. The deduction is capped at $500. Crucially, the basis is only reduced by the allowed deduction ($5,500 - $500 = $5,000), not the full paper loss.

Scenario B: PFIC Disposition Year

Setup: Continuing from Scenario A, the taxpayer sells all 100 shares on June 30, 2025, for $4,600.

• Sale Proceeds: $4,600
• Adjusted Basis (from 2024 EOY): $5,000
• Realized Loss: -$400
• Allowed Ordinary Loss: MIN($400, $0 UI) = $0
• Excess Treatment: The entire $400 is treated as a Capital Loss.

Scenario C: §1296(l) New Resident Basis Step-Up

Setup: Taxpayer B becomes a U.S. person on Jan 1, 2024, and elects MTM.

• 2015 Purchase Cost (500 shares): $20,000
• FMV on Jan 1, 2024: $45,000
• FMV on Dec 31, 2024: $48,000
• MTM Starting Basis (§1296(l)): MAX($45k, $20k) = $45,000
• 2024 MTM Income: $48,000 - $45,000 = $3,000 Ordinary Income
• The $25,000 pre-immigration gain ($45k - $20k) is deferred and will be recognized under standard §1001 capital gain rules upon eventual sale.

Official Treasury Reg. Cases for PFIC MTM

For engine verification, the following examples derived from the U.S. Treasury Regulations act as the absolute benchmark:

Official Case 1: UNI & §1291 Coordination (Reg. §1.1296-1)

Official Case 2: MTM Loss Floor Limitation (Reg. §1.1296-1)

Official Case 3: Pass-Through Entities (Reg. §1.1296-1)

Official Case 4: New U.S. Resident Step-Up (Reg. §1.1296-1)

Appendix: Complete Official Regulatory Cross-Reference

All statutory and regulatory sources that directly affect §1296 MTM calculation. Primary sources only — verify at Cornell Law or IRS.gov.

• 🔗 IRC §1296 Full Text (Core Statute): law.cornell.edu/uscode/text/26/1296
• 🔗 Reg. §1.1296-1 (MTM Election Execution): ecfr.gov/current/section-1.1296-1
• 🔗 Reg. §1.1296-2 (Marketable Stock Definition): ecfr.gov/current/section-1.1296-2
• 🔗 IRC §1291 Full Text (§1291 Coordination): law.cornell.edu/uscode/text/26/1291
• 🔗 IRC §1297 (PFIC Definition): law.cornell.edu/uscode/text/26/1297
• 🔗 IRC §1298 (PFIC Attribution / Ownership Rules): law.cornell.edu/uscode/text/26/1298
• 🔗 IRC §954(c) (FPHCI — CFC Shareholder §1296(f)): law.cornell.edu/uscode/text/26/954
• 🔗 IRC §1014 (Inherited Basis Step-up / §1296(i) Limit): law.cornell.edu/uscode/text/26/1014
• 🔗 Reg. §1.1012-1 (Lot Identification): ecfr.gov/current/section-1.1012-1
• 🔗 Form 8621 Instructions (Rev. 12/2025): irs.gov/instructions/i8621

Frequently Asked Questions (EA & CPA Edition)

Key MTM Regulatory Subsections Quick Reference

Official Sources and References

• 🔗 IRC §1296: Statutory framework for the PFIC Mark-to-Market election.
• 🔗 Treas. Reg. §1.1296-1: Detailed IRS regulations on Mark-to-Market tax adjustments and basis tracking.
• 🔗 Treas. Reg. §1.1296-2: IRS definition of qualified marketable stock for MTM eligibility.
• 🔗 IRC §1291: Taxation of default Passive Foreign Investment Companies and coordination rules.
• 🔗 IRC §1297: Definition of a Passive Foreign Investment Company (PFIC).
• 🔗 IRC §1298: Special PFIC rules, attribution, and annual reporting mandates.
• 🔗 IRC §951 & §954: Controlled Foreign Corporation (CFC) rules and coordination with PFIC MTM.
• 🔗 Treas. Reg. §1.1012-1: Tax basis determination rules and lot identification criteria.
• 🔗 Instructions for Form 8621 (PDF): Official IRS guidelines for reporting under the §1296 Mark-to-Market election.