Tempus AI, Inc. (TEM) — Reincorporation detail

Why this firm matters

Standard cohort firm (Completed). Included for breadth across destinations and sectors.

Vote outcome — reincorporation proposal

Approval standard: majority of the voting power of the outstanding stock entitled to vote (DGCL §266 conversion). Meeting type: annual.

Vote totals not yet pulled. Awaiting EDGAR Item 5.07.

Visual evidence — event study around the announcement

Per-firm event-study figures auto-built from event_study_announcement_json in the master database. Each panel is generated deterministically from the same data backing the cohort statistics — no firm-specific tuning, no cherry-picking.

Tempus AI's stock rose dramatically the day the move was announced

**Bottom line.** Tempus AI rose dramatically by 23.0% on announcement day. Across four different benchmarks for what "normal" should have looked like, no formal significance test was applicable.

This chart shows four different statistical lenses on what Tempus AI's stock did on the day the reincorporation was announced. Each lens compares the actual move against a different prediction of what "normal" should have looked like — peer firms, the broader market, a single matched competitor, or a raw side-by-side. The gold-edged bar marks the lens used in the cohort summary.

Method

Specifications: synthetic control on a sector peer pool, single-factor market model (S&P 500 benchmark), matched pair against a pre-specified primary peer, and raw differential. Estimation window: 240 trading days ending the day before the announcement. Standard errors via Patell-z (1976).

Tempus AI is one of the cohort's larger positive reactions

**Bottom line.** Tempus AI's reading sits in the positive tail of the cohort distribution. Cohort-wide mean is +0.69%; reactions vary widely by firm-specific factors, not destination state.

This chart shows every firm in the cohort that has a computed announcement-day abnormal return — sorted from largest negative to largest positive. Tempus AI is highlighted in gold. The dashed line marks the cohort-wide average, which is essentially zero. Even firms in the same destination state and same statutory regime can have very different reactions.

Method

Same headline-specification methodology applied to every firm in the 36-firm cohort that has 240 trading days of pre-announcement price history.

Data integrity. All figures generated by the same script (perfirm_gallery.py) on every release; SHA-256 verified at deploy time. See also: Cohort-wide event study →.

Event-study abnormal returns — announcement window

Returns around the announcement date.

Event date: 2025-03-28

Specification	Day-0 AR	Inference
Market-model abnormal return on announcement dayi	+23.01%	no inference

Event-study abnormal returns — vote window

Returns around the shareholder-vote (or written-consent) date.

Event date: 2025-08-07 · T0 source: actual_effective_date_iso · Estimation window: trailing 240 days; 240 valid after NaN drop

Specification	Day-0 AR	Inference
Market model (SPY benchmark) HEADLINEi	+5.96%	Patell-z p-value = 0.361

Long-run abnormal returns & pooled estimates

Buy-and-hold abnormal returns (1 / 3 / 6 / 12 months) and calendar-time portfolio alpha (CTE) post-effective.

Effective date: 2025-08-07 · n_post = 183 days

Buy-and-hold abnormal returns (BHAR)

Horizon & benchmark	BHAR	Inference
1 month vs S&P 500	+33.95%	Patell-z = +0.82 · p = 0.411 · n = 21 days
1 month vs sector ETF (XLV)	+29.72%	Patell-z = +0.82 · p = 0.411 · n = 21 days
3 months vs S&P 500	+32.57%	Patell-z = +0.25 · p = 0.800 · n = 63 days
3 months vs sector ETF (XLV)	+26.62%	Patell-z = +0.25 · p = 0.800 · n = 63 days
6 months vs S&P 500	-16.38%	Patell-z = -0.50 · p = 0.614 · n = 126 days
6 months vs sector ETF (XLV)	-29.85%	Patell-z = -0.50 · p = 0.614 · n = 126 days

Calendar-time portfolio alpha (CTE)

Specification	Annualized alpha	Inference
Calendar-time portfolio alpha vs S&P 500	-43.56%/yr	t = -0.86 · p = 0.390 · n = 183 days · Newey-West HAC SE (lag=5)
Calendar-time portfolio alpha vs sector ETF	-30.98%/yr	t = -0.52 · p = 0.603 · n = 183 days · Newey-West HAC SE (lag=5)

Cohort-level robustness battery

Heckman selection-corrected ATE · Romano-Wolf step-down + BH FDR · pooled BHAR. This firm's reading is shown in context of the full cohort.

Heckman two-step selection correction (controlled-vs-widely-held)

Cohort ATE = +0.94% (SE = 7.06%, n = 2395) after correcting for controller-status selection (inverse Mills ratio = -0.062).

Romano-Wolf step-down + Benjamini-Hochberg FDR (n = 47)

This firm: per-firm adjusted p-values pending. Multiple-hypothesis correction is computed across the full cohort to control family-wise error rate at alpha = 0.05.

Pooled cohort BHAR (mover firms only)

BHAR_63d: mean = -5.60% (SE = 22.11%, n = 3, p = 0.499) · BHAR_126d: mean = +17.33% (SE = 41.17%, n = 3, p = 0.774)

See Cohort event study → for the full battery and forest plots.

Source filings

Primary-source documents on SEC EDGAR plus IR / search links.

Classification & audit trail

Bucket

B2

Panel eligibility

PANEL_A_post_SB29

Audit status

VERIFIED

Source confidence

VERIFIED_VOTE

Transaction status

COMPLETED

Audit notes

Phase 3F: cleared future meeting_date_iso=2026-06-04 — firm already moved (eff_date=2025-05-23); the future date was the next annual meeting at the new domicile, not the reincorporation vote.
Phase 3F vote-result inferred APPROVED from status=COMPLETED + populated eff date (2025-05-23). Original vote_result was 'SCHEDULED'. Verify with 8-K if uncertain.
[2026-04-28] Phase 4I: replaced Google-search IR fallback with direct URL https://investors.tempus.com/
[2026-04-28] Phase 4K: corrected year error (announcement 2026-04-02 -> 2025-03-28). Annual meeting 2025-05-20; eff 2025-08-07 11:59pm ET. Class B 30-vote founder-control structure relevant for governance analysis.
[2026-04-28] Phase 4N: synthesized event_study_announcement_json from existing scalar CAR cells (phase4a_v2 join). Reviewer can extend with multi-spec analysis.
[2026-04-28] Phase 4Q: audit_status PENDING_TRANSACTION -> VERIFIED. Effective 2025-08-07. [2026-04-28] phase5c: vote source 8-K 0001193125-25-125425 (2025-05-23, Δ=3d) applied from EDGAR pull (status=AUTO_RESOLVED) [2026-04-28] phase5c: vote source 8-K 0001193125-25-125425 (2025-05-23, Δ=3d) applied from EDGAR pull (status=AUTO_RESOLVED) [2026-04-29] phase5r: bucket 'D' -> 'B2' (DE->NV effective 2025-08-07 >= SB29 -> bucket B2) [2026-04-29] phase5w: comprehensive validation by external reviewer across tranches v3 (4-version full residual walk, 269 substantive answers across 52 firms, 0 bucket drifts vs v3.58)
[2026-04-29] v3.75: VERIFIED via 8-K Item 5.07 — annual meeting May 20, 2025; effective Aug 7, 2025. Class A + Class B vote together as single class. DGCL §266 conversion. Board retained discretion to abandon despite shareholder approval (executed). Item 5.07 vote-tallies pincite pending.
v3.84-rev5c [2026-04-30]: TEM is_headline=false on panel_A_T0_announcement spec. Headline cohort statistics now exclude TEM (n=47 with headline AR; +0.26% bug fixed to -0.22%). TEM remains in the cohort for descriptive purposes; not used in the announcement-day headline.