Mecklenburg’s real disclosure this year is not the $83.8m he has sold. It is the 399,409 shares that left his GRAT.
Who · Gabriel M.I. Mecklenburg, Executive Chairman and co-founder, Hinge Health Inc | What · converted 200,000 Class B to Class A and sold 200,000 Class A in four tranches on 12 Oct 2026 at a blended $103.13, $20,626,371, under a plan adopted 12 June 2026 | Holding after · 0 Class A, 2,720,306 Class B
FORM 4 · MECKLENBURG GABRIEL M.I. · HNGE · 10/12/2026 · 10b5-1 box CHECKED, plan adopted 06/12/2026
Table I C 200,000 (A) $0 → 200,000 D
Table I S 8,642 $101.5308 → 191,358 | S 91,502 $102.5323 → 99,856
Table I S 59,988 $103.4755 → 39,868 | S 39,868 $104.3379 → 0
Table II Class B C 200,000 (D) → 1,644,004 D
Table II Class B 383,592 I, by Family Trust (no transaction)
Table II Class B 692,710 I, by GRAT (no transaction)
— compare FORM 4 · 04/01/2026 —
Table II Class B 1,793,102 D · 1,092,119 I by GRAT · 383,592 I by Family Trust · excludes 944,250 PSUs
A co-founder has taken his position to zero — a 100% cut — after $83.8m of selling in 2026 at prices running from $38 to $103. Read as a signal, it is the clearest kind: the man who built it is leaving at the top, with the stock near its high, and the aggregators are right to put it at the front of the insider tape.
“−100%” is measuring a transit account. Class A exists in his hands for hours. The number worth reading is in Table II: the GRAT has gone from 1,092,119 shares on 1 April to 692,710 on 12 October — −399,409, or −36.6% — while the Family Trust sits at 383,592 on both dates, unchanged. The estate plan is in its payback phase; the selling is the visible, uninformative half.
On the measurement. He converted exactly 200,000 Class B and sold exactly 200,000 Class A on the same date. The closing Class A balance is zero by construction, not by decision, and it has closed at zero after each of the ten sales on his 2026 record. A “percentage of holdings sold” computed on the Class A line will read −100% every single time, regardless of what he owns. That is a denominator that is not a choice variable.
On the GRAT, and why annuity payback is the better-supported read. Two hypotheses fit a shrinking GRAT line: the trust is paying its annuity back to the grantor in kind, or its term has ended and the remainder has passed to beneficiaries. They make opposite predictions about where the shares went. If the remainder passed out, the shares leave Section 16 reporting and his total falls. If the annuity is being paid in kind, they reappear in his direct line. His direct Class B went from 1,793,102 (1 Apr) to 1,644,004 (12 Oct) while 983,334 shares were converted out of it over that span — so the direct line was replenished by 834,236 shares. The GRAT’s 399,409 accounts for roughly half of that; Inference the balance is most likely PSU vesting, given the 944,250 performance units footnoted in April, but no filing in this set states the source. Direction of travel favours annuity-in-kind.
Why it matters. A GRAT paying its annuity back means the freeze was executed, the appreciation above the hurdle has already moved to the remainder beneficiaries, and the grantor is now receiving the principal he was always going to receive. Hinge Health has gone from $38 to $103 this year. Whatever that appreciation did for the remainder interest, it is done and outside his estate. The $83.8m of visible selling is the part that generates headlines; the 399,409 shares are the part that moved wealth between generations.
A Form 4 or Form 5 showing the GRAT line continuing to fall while his direct Class B falls alongside it. That pattern is a term-end distribution to remainder beneficiaries, not an annuity payback, and my read of the mechanism is wrong.
A proxy or S-1 beneficial-ownership table showing the GRAT and Family Trust aggregated into a single reported holding that has not moved at all. That would mean the line changes I am reading are reclassifications between vehicles, not transfers.
On the measurement claim there is nothing to falsify — the Class A balance closing at zero is arithmetic, not interpretation. What can be wrong is my inference about why the direct line replenished.
Ten reported sales in 2026, roughly 1,250,000 shares for about $83.8m, at 1 Apr ($38.45), 21 Apr ($45.05), 8 May ($55.01), 26 May ($53.79), 1 Jun ($60.22), 5 Jun ($65.53), 1 Jul ($85.05), 11 Sep ($88.97), 14 Sep ($93.22) and 12 Oct ($103.13). Every one under a 10b5-1 plan; every one convert-and-sell; every one ending at zero Class A. The 12 October tranche is the highest price and the second-largest size. Against that cadence, nothing about this filing is unusual — which is precisely why the −100% framing misleads.