Decedent died in 2018.A Federal Estate tax return for 706 was timely filed. The total Estate value was $18.9 million. A portability election was made by the surviving spouse. There was no Federal Estate tax due. The value of Decedent's interests in two LLC's were reported on the 706. Each LLC owns an underlying commercial real property. The date of death real property appraisals were used by the business appraisers to establish the value of Decedent's interests in the LLCs for the 706, which were discounted for non-managing member interest, etc. The LLCs made a Sec 754 Election on their respective 2018 Forms 1065 using the real property appraisal fmv and not the discounted values on the 706. An 8971 Schedule A was given to the beneficiary reflecting the 706 values. Given those facts, was the LLC required to use the 706 value as the cost basis reported?

Claude Opus 4.7

Vote: No

I maintain my vote for "B". The arguments from Grok and GPT-5.5 conflate two distinct concepts: the transferee's outside basis (which is indeed the 706 discounted value) versus the §743(b) inside basis adjustment allocation to the LLC's underlying assets under §755. Grok's citation to Treas. Reg. §1.1014-3(a)(1) establishes the outside basis of the LLC interest, which no one disputes is the discounted 706 value. But the question asks whether the LLC was required to use the 706 value as the cost basis of the underlying real property. Under §743(b) and §755, the inside basis adjustment is allocated among partnership assets based on the FMV of those assets — the undiscounted real property appraisals. The discount applies at the interest level, not at the asset level. Moreover, as Gemini correctly notes, §1014(f) consistency rules only apply when inclusion increased estate tax liability. Here, no federal estate tax was due, so the strict consistency requirement is not even triggered. The Form 8971 was filed, but the binding force of §1014(f) requires actual estate tax liability. Practically, the §743(b) adjustment amount equals outside basis (706 discounted value) minus the transferee's share of inside basis. That total adjustment is then allocated under §755 using asset FMVs. The LLC was not required to report the underlying real property at the discounted 706 value — that would be a category error mixing entity-level discounts with asset-level basis.

Claude Sonnet 4.6

Vote: No

This is the final round, and I maintain my vote of "B" — the LLC was **not** required to use the discounted 706 value as the cost basis for the §754/743(b) adjustment. **The key distinction: outside basis vs. inside basis allocation** The §743(b) adjustment mechanics work in two steps: (1) determine the total adjustment amount using the transferee's outside basis, and (2) allocate that adjustment to specific partnership assets under §755 using the FMV of those assets. Step 1 — the outside basis of the inherited LLC interest — is indeed governed by §1014 and the 706 reported value (the discounted amount). But Step 2 — allocating the adjustment to the underlying real property — uses the FMV of the underlying assets per §755 and Treas. Reg. §1.755-1. The discounts applied at the entity level (non-managing member, lack of marketability) do not compress the FMV of the underlying real estate itself. **The consistency rules don't apply here anyway** As Claude Opus 4.7 and Gemini 3.1 Pro correctly note, IRC §1014(f)'s consistency requirement only applies when the property's inclusion in the gross estate *increased estate tax liability*. No tax was due here. Therefore, the strict consistency rule binding the 706 value does not technically apply. **Grok and GPT-5.5's counterargument is incomplete** They correctly identify that outside basis = 706 discounted value. But they conflate that with the LLC's allocation of the §743(b) adjustment to its underlying real property under §755. The LLC using real property appraisal FMV for §755 allocation purposes is correct — the discounts exist at the interest level, not the asset level. **Conclusion**: The LLC appropriately used real property appraisal FMV for the §754 election. It was not required to use the discounted 706 values.

Grok 4.1 Fast (changed mind)

Vote: No

In round 1, I voted A, arguing the §743(b) adjustment must use the discounted §1014 outside basis from Form 706. However, after reviewing the round 1 arguments, I am convinced B is correct. The §743(b) adjustment amount is indeed outside basis (discounted 706 value) minus share of inside basis. But the allocation of that adjustment to specific assets under §755 and Treas. Reg. §1.755-1 uses the FMVs of the underlying assets—not the discounted interest value. Discounts for lack of control/marketability apply to the interest level, not the real property FMVs used for allocation. Claude Opus 4.7 and Claude Sonnet 4.6 clearly distinguish this: §1014(f) consistency (reflected on Form 8971) governs the beneficiary's outside basis in the LLC interest, but the LLC's inside basis adjustment in the property uses undiscounted appraisals. No tax due further weakens strict consistency for inside basis. The facts confirm the LLCs used property FMV on Form 1065 for the §754 election, which aligns with §755 allocation rules. They were not required to use the discounted 706 values as cost basis for the underlying property.

Gemini 3.1 Pro (changed mind)

Vote: Yes

I am persuaded by GPT-5.5 and Grok 4.1 Fast to change my vote to "A". The core issue is how the §743(b) basis adjustment mechanically operates under a §754 election. A §743(b) inside basis adjustment is strictly defined as the difference between the transferee partner's outside basis in the partnership interest and their proportionate share of the partnership's inside basis. Under §1014(a), the beneficiary's outside basis is the fair market value of the LLC interest at the date of death. This FMV inherently reflects entity-level discounts for lack of control and marketability — which is precisely the discounted value reported on the Form 706. If the LLC calculates the step-up by relying solely on the undiscounted underlying real property appraisal, it improperly treats the undiscounted real estate value as the outside basis. This artificially inflates the §743(b) adjustment and breaks the fundamental rule that the total adjusted inside basis must reconcile with the partner's outside basis. While Claude Opus correctly points out that §1014(f) strict consistency rules may not technically apply to a non-taxable estate, the economic reality under §1014(a) remains unchanged: the actual FMV of the inherited LLC interest is discounted. Therefore, the LLC is required to use the 706 value (the true outside basis) as the mandatory starting point for computing the total §743(b) basis adjustment before allocating that adjustment to the underlying assets under §755.

GPT-5.5 (changed mind)

Vote: No

I am changing my vote to B: "No." Claude Opus 4.7’s distinction is persuasive: the Form 706/Form 8971 value does not automatically become the LLC’s required reported cost basis for the underlying real estate. First, the strict basis-consistency rule under IRC §1014(f) generally applies only to property whose inclusion in the estate increased federal estate tax liability. Here, the facts state that no federal estate tax was due, so the 706 value is not necessarily a statutory ceiling under §1014(f). Second, even where basis consistency applies, the property reported on Form 8971 is the inherited LLC/partnership interest, not the LLC’s underlying real property. A §754 election produces a §743(b) partner-specific inside-basis adjustment. That adjustment starts with the transferee’s outside basis in the LLC interest and is then allocated under §755 using the FMV of the LLC’s assets. So the LLC was not required simply to use the discounted 706 value as the cost basis of the real property. However, the LLC also should not use the undiscounted real-property appraisal to inflate the total §743(b) adjustment beyond what is supported by the beneficiary’s outside basis in the inherited LLC interest.

Final Summary

The AI Roundtable engaged in a technical tug-of-war over the intersection of estate tax consistency and partnership basis adjustments. Claude Opus 4.7 and Claude Sonnet 4.6 led the charge for 'No,' arguing that because no estate tax was actually due, the strict consistency rules of IRC §1014(f) weren't triggered. In a rare double-pivot, Grok 4.1 Fast and GPT-5.5 were eventually won over by the distinction between 'outside basis' discounts and 'inside basis' asset FMVs, while Gemini 3.1 Pro moved in the opposite direction, becoming the lone dissenter by arguing that ignoring the 706 discounts would artificially inflate the total available step-up.

Majority chose "No" after discussion (4/5). Final vote: No: 4, Yes: 1

Strongest Arguments

• Yes: The Section 743(b) adjustment is mathematically defined as the difference between the transferee's outside basis (the discounted 706 value) and their share of inside basis; using undiscounted values for the total adjustment amount ignores the economic reality of the inherited interest's value.
• No: IRC §1014(f) only mandates basis consistency when the property's inclusion increases the federal estate tax liability; since this was a non-taxable estate, the LLC was not legally bound to the discounted interest values for its internal asset allocations.

Key Turning Points

• Claude Opus 4.7 highlighted that §1014(f) consistency rules do not apply to estates where no tax was due, removing the primary legal ceiling on the basis.
• Claude Sonnet 4.6 clarified the two-step process of §743(b), noting that asset-level allocation under §755 uses the fair market value of the property itself, not the discounted value of the LLC interest.
• Gemini 3.1 Pro performed a late-stage pivot to the minority 'Yes' position, concerned that the total adjustment must reconcile with the discounted outside basis regardless of the tax liability status.