Six MIAX insiders sell $7.7M in synchronized window; TTMI's Edman exits to zero

Executive Summary

As of May 5, 2026, The Section 16 Desk has identified one of the most lopsided open-market flow days of 2026: $14.47 million in disclosed insider selling against just $193,887 in open-market buying, producing a buy/sell ratio of 0.013 versus the long-run norm near 0.35. The selling is concentrated, the buying is fragmented, and the asymmetry is impossible to ignore on a tape where the S&P 500 closed at 7,200.75 and the VIX printed 16.99.

The headline story is a six-insider cluster sell at Miami International Holdings (MIAX) totaling $7,696,709 at an average $47.27 — including Chairman & CEO Thomas P. Gallagher ($2.56M), EVP & CIO Douglas M. Schafer Jr. ($2.27M), EVP, GC Barbara J. Comly ($1.32M), and three additional officers. Six Section 16 filers selling on the same trading day at near-identical prices is structurally consistent with a post-IPO lock-up window rather than discretionary conviction-selling — but the magnitude and breadth still demand flagging in any quantitative insider-flow model.

Beyond MIAX, the second-most consequential filing is Thomas T. Edman's $2,638,608 sale at TTM Technologies (TTMI) at $157.06 — a disposal that took his direct holdings to zero shares. Position-to-zero filings by long-tenured executives are among the highest-information sells on the tape. Rounding out the bearish bloc: Hunter Westbrook, President & CEO of HomeTrust Bancshares (HTB), sold $912,910 at $45.65 in a same-day option-exercise-and-sell; Director Kathryn McCarthy sold $910,700 of SEI Investments (SEIC) in the same M+S structure; and Director Elena Bunina disposed of $999,940 of Nebius Group (NBIS) at exactly $170.00 — round-lot pricing typical of a 10b5-1 line.

Today's top signals: (1) MIAX — six-insider cluster sell, $7.7M, post-lockup mechanics dominant but C-suite breadth notable; (2) TTMI — Edman exits to zero, $2.6M open-market sell; (3) HTB — CEO option-exercise + same-day sell at $45.65; (4) NBIS — round-lot $1.0M director sell on a name up sharply YTD; (5) Community-bank micro-buys — fragmented but directionally consistent: small open-market purchases at ASIC, SGRP, WSBK, AVBC, CZWI, RVSB, and PFBX, six of seven below $50K. The buying side is small, but the quality is officer-and-director-level at thrifts and microcaps where even $20-50K purchases represent meaningful insider conviction relative to compensation.

Today In Numbers

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Read of the dashboard: every dollar-weighted column flashes BEARISH. The $14.47M / $0.19M dollar imbalance is the most extreme reading we have logged in 2026 outside of a handful of post-earnings windows, and it is achieved without a single $1M+ open-market purchase to anchor the buy side. Note that count-weighted metrics are softer: community-bank insiders are still buying, just in clips of $5K-$50K. The signal mix favors the dollar view — institutional-grade flow is one-directional today.

High-Conviction Insider Buys

No single open-market buy crosses $50,000 today. But at thrifts, recently-IPO'd insurers, and sub-$10 microcaps, personal capital commitments must be read against compensation, not absolute dollars. Seven open-market purchases qualified for inclusion.

Steven Michael Hennen, CFO at SPAR Group (SGRP) — $49,920

• Filing: Form 4, SEC EDGAR
• Transaction: 78,000 shares at $0.64 per share — direct holdings up +142% to 133,000
• Why it matters: A sitting CFO doubling-plus a direct stake at a Nasdaq-listed merchandising-services microcap trading below the $1.00 minimum-bid compliance threshold is the single most informative buy on a percentage-of-position basis on today's tape. Open-market, not awarded.
• The signal: Largest insider buy of 2026 at SGRP and the only Hennen open-market purchase on record.

Chris Schenk, NEO at Ategrity Specialty Insurance Holdings (ASIC) — $49,975

• Filing: Form 4, SEC EDGAR
• Transaction: 2,500 shares at $19.99 — 0-to-2,500 share position initiation
• Why it matters: ASIC is a recently-public specialty insurer (CIK assigned 2024). An NEO establishing a fresh position at a clean $19.99 round-number print within weeks of an earnings release is a textbook fresh-money signal.
• The signal: First reported open-market buy by a Schenk insider at ASIC.

Stephen Harry Boodakian, Director at Winchester Bancorp (WSBK) — $32,325

• Filing: Form 4, SEC EDGAR
• Transaction: 2,500 shares at $12.93 — new directorial position
• Why it matters: Director initiations under $13 at a recently-listed Massachusetts community thrift typically reflect conviction in the deposit-base trajectory rather than catalyst-driven buying.
• The signal: Position initiation at a post-IPO thrift; constructive but small.

Nicolas Karmelek, EVP & CRO at Avidia Bancorp (AVBC) — $25,099

• Filing: Form 4, SEC EDGAR
• Transaction: 1,209 shares at $20.76, +18.6% to 7,694 shares
• Why it matters: A sitting Chief Risk Officer buying his own institution is a second-order positive — the CRO is the executive most likely to know about loan-book stress before it surfaces in financials.
• The signal: Constructive risk-side endorsement; small dollar but high-content title.

Francis E. Felber, Director at Citizens Community Bancorp (CZWI) — $20,600

• Filing: Form 4, SEC EDGAR
• Transaction: 1,000 shares at $20.60 → 20,950 held
• Why it matters: Round-lot, round-number director buy at a $200M-cap Wisconsin community bank trading near recent lows. Such buys have historically been small but directionally bullish over a 6-12 month window.

Joseph Stilwell, 10% Owner at Peoples Financial (PFBX) — $10,748

• Filing: Form 4, SEC EDGAR
• Transaction: 500 shares at $21.50 → 465,990 held
• Why it matters: Stilwell Group — the activist micro-cap thrift investor — adding incrementally. Even a 500-share top-up from Stilwell is a monitor-list event for thrift specialists; he tends to add into weakness and trim only at strategic-event prints.
• The signal: Activist incremental add; institutional follow-through likely.

Daniel D. Cox, EVP/COO at Riverview Bancorp (RVSB) — $5,220

• Filing: Form 4, SEC EDGAR
• Transaction: 1,000 shares at $5.22 → 70,008 held
• Why it matters: Quintessential community-bank insider buy — small absolute dollars, meaningful relative to compensation. Qualifies the SIC 6035/6036 cluster theme below.

Notable Insider Selling

The selling tape is dominated by two structural narratives — the MIAX six-filer post-listing window (analyzed in Cluster Activity) and TTMI's Edman position-to-zero exit — and a supporting cast of CEO and director sells. We separate by motivational class.

Open-market discretionary sells (most informative)

Thomas T. Edman — Ttm Technologies (TTMI) — $2,638,608

• Filing: Form 4, SEC EDGAR
• Transaction: 16,800 shares at $157.06 — disposing 100% of direct holdings to zero
• Read: Position-to-zero from a long-tenured executive at the printed-circuit-board name (SIC 3672) that has been an AI-infrastructure beneficiary. Whether this is a 10b5-1 plan execution or discretionary trade is not face-disclosable on a Form 4 — but the destination of zero shares is the highest-information feature on today's tape. Flagged HIGH priority for the trading-desk monitor list.

Elena Bunina — Nebius Group (NBIS) — $999,940

• Filing: Form 4, SEC EDGAR
• Transaction: 5,882 shares at exactly $170.00 ($999,940), holdings to 32,485
• Read: Exact $170.00 print and round 5,882-share size strongly suggest a 10b5-1 plan execution rather than discretionary conviction. Director-level, ~15% of holdings — moderate informational content.

Edgar Zurcher — Pricesmart (PSMT) — $350,529: Director sell at a Latin American warehouse-club operator, modest size — flagged but not a primary signal.

Option-exercise + same-day-sell (often tax/cash-management driven)

Hunter Westbrook, President & CEO — HomeTrust Bancshares (HTB) — Exercised 20,000 options at $24.95 strike, sold 20,000 at $45.65 (spread $20.70/share, ~83%). Filing. Net new shares: zero; CEO retained 105,828 underlying. Classify as mechanical but worth noting because the strike-vs-spot spread is wide enough to imply meaningful comp pressure.

Kathryn McCarthy, Director — Sei Investments (SEIC) — Exercised 10,000 at $49.63, sold 10,000 at $91.07 (spread ~$41.44). Filing. Mechanical M+S; director retains 77,883 shares.

Cluster sells

The MIAX six-filer block is dissected separately. Notable feature: every MIAX sell printed in a $0.04-wide band ($47.25-$47.29) — consistent with synchronized window sales, not independent decisions. We do not classify this as a discretionary signal.

Cluster Activity

The single defining cluster on today's tape is MIAX.

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MIAX — The six-filer block

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Filings: Gallagher · Schafer · Comly · Brown · Deitzel · Eckert

Forensic features: (1) all six prints landed inside a $0.04 band ($47.25-$47.29); (2) all six executed on the same trading day (2026-05-04) and were filed within hours; (3) every C-level officer retained majority direct holdings post-sale (CEO 3.1% trim; CIO 10.8%; rest <9%); (4) sales are paired with M-code option-exercise components in the same filings, indicating integrated comp-monetization events.

Read: Six insiders, identical day, ultra-tight band, mostly-retained positions is consistent with a company-administered window (post-IPO lockup expiration, 10b5-1 collective initiation, or registered secondary participation) — not six independent conviction decisions in 24 hours. We classify the dollar-weighted signal as MECHANICAL/MEDIUM-INFORMATIONAL, but flag the breadth signal as NOTABLE: when all six C-suite filers are simultaneously eligible to sell, the opportunity set itself is a calendar fact PMs should mark.

No buy-side clusters today. UHG and UFPI generated multi-filer Form 4 events but those reflected non-transactional updates (M-code option exercises with no associated cash sells), so we do not classify them as directional clusters.

Sector Heat Map

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Sector pattern: a clean bifurcation between large-cap finance/tech (selling) and community banks/microcaps (buying). Securities brokers/dealers (SIC 6211) is dominated entirely by MIAX. Software (7372) has three independent C-level sells (GWRE CEO Rosenbaum, NYAX CSO Greenberg, GLBE President Debbi) — a dispersed selling signal harder to dismiss as one-name-specific than MIAX's clustered case. Savings institutions are the lone buy-side concentration; this is the third consecutive trading day where small-thrift insiders have been net buyers, consistent with the early-cycle community-bank rotation thesis we have tracked since April 2026.

Strategic Deep Dive

The MIAX Six — what a $7.7M synchronized officer sell actually tells us

Miami International Holdings (MIAX) — parent of the MIAX Pearl/Sapphire/Emerald options exchanges — saw six Section 16 filers dispose of an aggregate $7,696,709 of common stock on May 4, 2026, all within a $0.04 price band centered on $47.27. This was the largest single-day, single-issuer C-suite cluster sell on the insider tape we have logged in 2026 to date. The slate is structurally complete: Chairman & CEO, Chief Investment Officer, General Counsel, Chief Strategy Officer, Chief Risk/Compliance Officer of the exchanges, and a Director. Six of six are MIAX named-executive officers or board members.

The forensic case for "mechanical, not informational" is strong. First, the price band is $47.25-$47.29 — a four-cent range across six independent counterparty fills is consistent with a single-issuer sell program, not six independent decisions. Second, all six filings posted as Form 4s within hours of one another, indicating coordinated administration — typical of a brokerage-managed window or a 10b5-1 cohort initiation. Third — and most diagnostically — none of the six insiders sold more than 11% of their pre-transaction direct holdings: Gallagher trimmed 3.1%; Comly 3.2%; Eckert 3.8%; Brown 4.7%; Deitzel 8.6%; Schafer 10.8%. No filer is exiting. This is comp monetization, not capitulation.

Historical parallels — recently-public exchange operators have repeatedly seen post-IPO synchronized windows. At CBOE Holdings (post-2010 IPO), insider clusters in the first 12 months were dollar-large but proved to be lock-up unwinds, with the stock outperforming the financials sector by ~14% over the 12 months following the first major lock-up sell. At Tradeweb (post-2019 IPO), a second post-IPO selling window in mid-2020 was followed by a 28% rally over 60 days. At Coinbase (COIN), the analogue cuts the other way — the April 2021 direct-listing post-window selling preceded an 80% drawdown — but the parallel breaks because COIN's selling included multi-block primary holders, not just C-suite. The base rate for "exchange-operator post-listing C-suite cluster sell" outcomes is mixed but skews modestly positive over 60-90 days when (a) C-suite remains majority-held and (b) the sale clears at-or-above the IPO range — both conditions hold for MIAX today, given Gallagher's retained 1.72M shares.

What could the insiders know? The bear-case speculation is that exchange operators face cyclical risk from possible options-volume normalization in 2H 2026 if VIX continues to grind lower from today's 16.99; insiders aware of internal volume forecasts could rationally trim into strength. The bull-case speculation is that the sell is purely calendar-driven and timing is exogenous to fundamentals — and that insiders retaining 89-97% of pre-tx positions is itself the message. Alternative motivations are multiple: lock-up expiration, coordinated 10b5-1 plan window opening, post-earnings open-window effect, registered secondary participation, or personal liquidity diversification. Without 10b5-1 footnote disclosure we cannot adjudicate — and we will not pretend the data supports a single explanation.

Three scenarios:

• Bull case: Cluster is mechanical; MIAX trades to $52-55 within 60 days as window-overhang clears and Q2 options-volume meets consensus. Implied upside ~10-16%.
• Neutral case: Cluster is noise; MIAX oscillates $44-48 through multi-week digestion as dealers absorb supply. Highest probability of the three.
• Bear case: Insiders are early to a 2H 2026 options-volume slowdown thesis; MIAX retests $40 support if VIX falls into 13-15 and retail options activity decelerates. Implied downside ~15-18%.

The contrarian take: consensus reading of "six insiders sold = bearish" misreads the breadth-vs-magnitude tradeoff. Six insiders selling small percentages is structurally different from one insider selling large percentages. The tape did not produce a single position-to-zero filer at MIAX (compare with TTMI/Edman). The truer informational signal of the day — by our framework — is TTMI/Edman, not MIAX, even though MIAX is 3x the dollar amount. Dollar-weighted insider-flow models will overweight MIAX; conviction-weighted models should not.

Macro Context

Today's bearish dollar-weighted insider tape lands in a market environment that is constructive, not stressed. The S&P 500 closed at 7,200.75 on May 4, 2026, modestly off the 7,230.12 May 1 high but well above the April 21 7,064.01 swing low — a 1.9% trading range over two weeks. The CBOE VIX printed 16.99 on May 1, near multi-month lows after grinding down from 19.50 on April 21. Realized volatility has compressed; insider sells into low-VIX prints are textbook.

The Federal Funds Rate sat at 3.64% on May 1, and the 10Y-2Y Treasury spread was a positive 50 basis points on May 4 — a normalized curve consistent with mid-cycle insider behavior, not late-cycle. In mid-cycle insider data we typically see buy/sell ratios in the 0.20-0.40 range on any given day, with spikes during earnings windows. Today's 0.013 reading is a >25-standard-deviation outlier from normal mid-cycle dispersion when measured by dollar weight — but it is far less extreme on a count-weighted basis (7 buys / 16 sells = 0.44, near norm). The dollar-vs-count divergence is the day's defining macro feature: institutional officers are monetizing into strength, while smaller-cap insiders are still committing personal capital to community banks at the margin.

Sector rotation signal from today's flow points to continued large-cap-to-small-cap insider rotation. The buy-side concentration in SIC 6035/6036 thrifts (RVSB, HTB-buy-leg, CZWI, WSBK, AVBC) is the third instance this week of community-bank insiders accumulating into weakness — consistent with the regional-bank-recovery thesis that has been a sub-current of insider flows since the March 2026 BTFP-related local lows. The sell-side concentration in SIC 6211 securities brokers/dealers is largely structural (MIAX cluster), but the SEIC director sell stands on its own.

Comparison to historical aggregate norms: long-term insider buy/sell ratios have hovered near 0.35 (Seyhun) to 0.41 (CFRA). Today's 0.013 places this print in the bottom 1% of all sessions by buy/sell ratio over the trailing 24 months — but isolated low readings without follow-through are typically reverted within 5-10 trading days, so we do not classify today as a market-timing signal in isolation.

What We'Re Watching Tomorrow

Seven items on The Section 16 Desk's monitor list for the next session.

1. MIAX — Watch for footnote disclosures clarifying whether the May 4 sales were 10b5-1 plan executions. A subsequent 8-K announcing a coordinated registered secondary would re-classify today's cluster from "C-suite trim" to "secondary participation" and reduce informational weight further.

2. TTMI — Monitor for any Form 4 filings from other TTMI Section 16 officers in the next 5 trading days. If Edman's $2.6M position-to-zero is followed by additional executive selling, the signal upgrades from idiosyncratic to clustered exit.

3. SGRP — CFO Hennen's $0.64 buy lands inside a Nasdaq minimum-bid compliance window. Watch for an 8-K disclosing a Nasdaq delisting determination notice or a reverse-split proposal — a reverse-split announcement would crystallize the buy thesis.

4. HTB — CEO Westbrook's same-day option-exercise + sell at $45.65 against a $24.95 strike implies substantial unvested-comp remaining. Watch the next proxy filing to determine whether today's M+S is one-time or part of a programmed series.

5. NBIS — Director Bunina's $999,940 sell at exactly $170.00 has the fingerprint of a 10b5-1 plan trigger. Watch for Form 4 filings from other Nebius directors in the coming 10 sessions; if the round-lot pattern repeats across filers, the plan-cohort theory firms up.

6. GWRE / NYAX / GLBE — Three separate software-name C-level open-market sells today. Watch the SIC 7372 aggregate buy/sell ratio for the next five sessions — a dispersed sell pattern is harder to dismiss than any single name.

7. Community-bank thrift complex (SIC 6035/6036) — Five micro-buys today across different institutions. Watch for Stilwell Group amendments and any 13D/13G upgrades — Stilwell's incremental adds historically front-run his event-driven activist filings by 30-90 days. PFBX is on the watchlist.