1Share Holdings10 SharesClass ABasis = 3010 SharesClass BBasis = 90Shareholder J(Individual)Corp X2MergerSurrenderCorp XShares10 SharesCorp Y Stock &$100 of CashMergeShareholder J(Individual)YShareholdersCorp XCorp YClass AClass BShares of Y50Cash50Total consideration100Less basis(30)Realized gain70Recognized gain505050100(30)1010(lesser of gain realized or boot received)LegendOwnership / structural holdingTransfer of stock / cash / assetsMerger step

Pro Rata Boot Allocation Explained

J, an individual, holds 10 shares of Class A stock of Corporation X (basis $30) and 10 shares of Class B stock of Corporation X (basis $90). On Date 3, Corporation Y acquires the assets of Corporation X in a reorganization under section 368(a)(1)(A). Pursuant to the plan, J surrenders all of J’s Corporation X stock in exchange for 10 shares of Corporation Y stock and $100 of cash. Each Class A share, each Class B share, and each Corporation Y share is worth $10, so J receives $100 of Corporation Y stock and $100 of cash for $200 of surrendered stock.

Because the terms of the exchange do not specify that the cash is received for particular Class A or Class B shares, Treas. Reg. § 1.356-1(b) requires the cash to be allocated pro rata by the fair market value of the surrendered shares. J is therefore treated as receiving $50 of Corporation Y stock and $50 of cash for the Class A shares, and $50 of Corporation Y stock and $50 of cash for the Class B shares.

The gain is computed separately for each block. On the Class A shares, J realizes $70 of gain ($100 consideration − $30 basis), $50 of which is recognized under section 356(a) as the lesser of gain realized or boot received. On the Class B shares, J realizes $10 of gain ($100 consideration − $90 basis), all $10 of which is recognized. Assuming the recognized gain is not treated as a dividend under section 356(a)(2), it is treated as gain from the exchange of property.

Key Takeaways

Pro rata when terms are silent

If the plan does not specify which shares the boot is paid for, the cash is allocated across all surrendered shares in proportion to their fair market value.

Gain computed block by block

Realized gain is measured separately for the Class A block ($70) and the Class B block ($10) using each block’s own basis.

Recognition capped by boot

Under section 356(a), recognized gain is the lesser of gain realized or boot received — $50 on the Class A shares and the full $10 on the Class B shares.

No aggregation of loss and gain

Because gain is tested per share block, a high-basis block cannot shelter the gain on a low-basis block; each block stands on its own.