The practical answer

Build the shareholder workbook from the transaction-date ownership records and keep recipient identity, shares exchanged and reporting disposition separate. Resolve duplicate accounts and intermediary holdings before turning source rows into proposed CAP records.

This guide is for corporate tax teams preparing 2026 shareholder data after the transaction's reporting framework has been reviewed. Its fictional register illustrates data reconciliation and does not determine an exemption or the legal owner of a real holding.

Fix the ownership snapshot used for the transaction

Obtain the stock ledger or transfer-agent extract supporting the relevant exchange. Record its effective date, extraction date and version. A current capitalization table can differ from the transaction-date shareholder population because of later transfers or administrative changes.

Keep security class, account reference, shares and holder identity on every source row. Do not merge common and preferred positions merely because they have the same mailing address. Preserve subclasses or series where they distinguish the interests exchanged.

Compare the source population with the closing share schedule. Identify missing accounts, cancelled positions and unmatched share classes before enriching the register with tax-recipient information. A balanced ownership total makes the later allocation review easier to trace.

Separate stock-ledger holder data from reporting-recipient decisions

The IRS CAP instructions contain shareholder exceptions and specific clearing-organization rules. A ledger holder, beneficial owner, broker and reporting recipient are not automatically interchangeable. Keep their roles explicit and ask the advisers to resolve the applicable reporting treatment.

Record proposed recipient identity with a source reference, plus a separate reviewed disposition such as included, exception supported or unresolved. These are workbook labels, not IRS filing statuses. Attach the basis for an exception rather than treating a blank recipient field as an approved exclusion.

For intermediary holdings, preserve the original account and related ownership support. Do not create both intermediary and underlying-owner forms from the same shares without a reviewed explanation of the reporting population.

Validate identity and account fields against documented sources

Shareholder workbook fields
Field groupSourceCheck
Legal recipient name and TINApplicable tax documentationResolve conflicting identities through documented review
AddressCurrent recipient delivery recordPreserve foreign address components where relevant
Account referenceStock ledger or transfer-agent recordKeep a stable link to the original holding
Shares and classesExchange-date ownership scheduleReconcile quantities by class
Reporting dispositionAdviser conclusion and supporting certificateSeparate reviewed exceptions from open questions

IRS Publication 1099 provides the general recipient-data framework. Keep sensitive identifiers in the protected preparation system; use internal row references in broadly shared review notes.

Worked example: four source accounts become three proposed recipients

Fictional 2026 example. Assume advisers have established the relevant reporting scope for a larger qualifying transaction. A small extract of its shareholder register contains four common-share accounts. Documented review establishes that two accounts belong to the same recipient and may be combined for this example.

Fictional source-to-recipient mapping
Source accountInternal recipient referenceShares exchangedDisposition
Account ARecipient R1100Included
Account BRecipient R2200Included
Account CRecipient R3120Included
Account DRecipient R3180Same recipient, documented combination

The source total is 600 shares: 100 + 200 + 120 + 180. The proposed recipient rows retain 100, 200 and 300 shares, also totaling 600. Three proposed recipients do not mean one source account disappeared.

The workbook keeps the C and D links underneath R3. If their tax documentation actually identified different owners, the team would leave them separate and investigate. Similar names or addresses alone would not justify the combination.

Resolve duplicate accounts and exceptions without losing shares

Compare legal identity, source account, share class and supporting documentation before marking a duplicate. Distinguish an identical repeated export row from two valid holdings of one recipient. Removing a true holding can make both share quantities and consideration allocations incomplete.

For every excluded or unresolved row, retain the shares and the reason in a reconciliation category. The ownership population should bridge to included, documented exception and unresolved groups. Do not drop exception rows before they contribute to that completeness check.

Ask the responsible reviewer to resolve conflicting tax documentation or intermediary roles. Record the conclusion and source date. If ownership evidence changes later, update the mapping through a visible revision so the consideration workbook can be refreshed consistently.

Retain a cross-reference when the transfer agent changes an account identifier during the project. An identifier change can otherwise look like a new shareholder and duplicate the same holding. Compare the effective dates and documented share movement before deciding whether the old and new account rows describe one position or two.

Freeze the reviewed population for consideration preparation

Save a versioned population with the source extracts, mappings and exception support. Record the totals by share class and the number of proposed reporting records. These are different controls: share quantities measure the ownership bridge, while record counts describe the preparation output.

The CAP instructions require an account number when multiple accounts for a recipient produce more than one CAP and encourage account references generally. Preserve those identifiers in the preparation design so later corrections can locate the right record.

Pass the reviewed population to the consideration and filing teams with unresolved items clearly identified. The workbook should allow them to trace every proposed recipient back to the original holdings and understand why any source account was combined, excluded or left pending.

Reconcile shareholder accounts to a reviewed CAP population

Reconcile shareholder accounts to a reviewed CAP population: Capture transaction-date holdings; Map recipient identities; Resolve combinations and exceptions; Freeze the reviewed register
A source-account count and a proposed-recipient count can differ without losing share coverage.
Read the workflow as text
  1. Capture transaction-date holdings. Keep source accounts, share classes and quantities.
  2. Map recipient identities. Use tax documentation and distinguish intermediaries.
  3. Resolve combinations and exceptions. Retain every source holding in the quantity bridge.
  4. Freeze the reviewed register. Pass versioned recipient rows and source links to preparation.

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Put this guide to work

CAP shareholder source and exception workbook

Save the editable text worksheet and use it with your own records. Keep completed copies in your secure working files.

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Common questions

Can I use today's capitalization table?

Use the ownership evidence supporting the relevant exchange. Later changes can make a current table differ from the transaction-date population.

Are two accounts with the same address duplicates?

Not necessarily. Compare legal identity, account history and supporting tax documentation before combining or excluding records.

Should exception rows be deleted?

Retain them in the ownership bridge with their documented disposition. This preserves completeness even when a reporting record is not prepared.

Can I report both a broker and underlying owner automatically?

No. Intermediary and clearing-organization rules require review. Preserve the roles and ask which recipient population applies.

Which totals should the workbook show?

Show shares by class, source-account counts, proposed-recipient counts and unresolved or exception groups. Each checks a different part of the preparation.

Official sources and scope

Sources checked September 5, 2026. Use the edition for the tax year and filing method you are working with; later instructions may change thresholds, fields, or procedures.

  1. IRS Form 1099-CAP instructions

    April 2025 continuous-use instructions for 2025 and subsequent years until superseded: reporting scope, exceptions, shareholder fields and consideration definitions.

  2. IRS Publication 1099

    2026 General Instructions for Certain Information Returns: recipient data, account references, corrections and filing/furnishing framework.