UTHR Counsel Paul Mahon Banks $14.4M Across Three Sessions

Paul Mahon, United Therapeutics' EVP and General Counsel, has run a regimented option-exercise and open-market sale cadence across three Form 4 filings in the past six weeks. Each session is identical in structure: 8,300 options exercised at a $146.03 strike, paired with the sale of 8,300 common shares at then-prevailing market prices. The three sessions and accession numbers:

Session	Sale Range	Shares Sold	Proceeds	Accession
2026-04-02	$565 - $573	8,300	$4.70M	0001231589-26-000009
2026-04-16	$574 - $578	8,300	$4.79M	0001231589-26-000010
2026-05-07	$583 - $598	8,300	$4.87M	0001231589-26-000011
Total		24,900	$14.36M

The strike-side cost across all three sessions is roughly $3.64M ($146.03 × 24,900). Net intraday spread captured: approximately $10.72M before taxes.

This Is What 10b5-1 Looks Like When You See It in the File

Three sessions, identical share counts (8,300 each), executed roughly two weeks apart, with the only variable being the market price on the day. That pattern — the textbook output of a Rule 10b5-1 trading plan — does not require speculation. Mahon's recent filings show the mechanics: a pre-set schedule converts options into liquidity on a calendar that the executive did not control at the time of each individual transaction. The discretionary view, to the extent there was one, lives in the date the plan was adopted, not in the date of any individual sale.

For investors reading Form 4 filings as a sentiment proxy, this matters. A discretionary sale of $4.87M at $597 on May 7 would be a same-week directional read. A 10b5-1 sale of $4.87M at $597 on May 7 was scheduled months earlier and is mechanical. The market gets the same supply hitting the tape either way, but the signal density to a fundamental investor is materially different.

Reading This Alongside the CEO Pattern

Mahon's filings sit inside a broader pattern at United Therapeutics. CEO Martine Rothblatt's own recent Form 4 history shows a similar exercise-and-sell cadence at materially larger size. When two senior officers — General Counsel and CEO — are simultaneously running biweekly liquidation plans against the same option grants, the read is straightforward: the company's RSU/option vesting calendars have aligned across the senior leadership team, and 10b5-1 plans were adopted in a coordinated window. That does not signal bearishness on UTHR fundamentals. It signals that the senior team is converting historical compensation into cash on schedule, which is what 10b5-1 plans exist to do.

For the holder base, the practical implication is that UTHR's daily traded supply has a predictable insider component for the next several months. The next two scheduled Mahon sessions would land roughly May 21 and June 4 if the biweekly cadence holds.

The Ownership Math

After the May 7 sale, Mahon's reported common-stock balance in the largest of his ownership lines stood at approximately 45,172 shares. He retains a separate 300-share derivative-account balance reported on Form 4 Table II. The lifetime Form 4 record shows $259.0M in cumulative sales against zero open-market buys — a directional history consistent with an executive whose UTHR compensation is delivered in options and stock and whose personal financial planning runs through scheduled liquidation programs.

Crucially, the May 7 "Shares after latest sale: 300" figure that appears in some screening tools refers to a derivative-account residual after the cluster of option exercises, not to total UTHR ownership. The full common-stock position, plus separate trust and family-vehicle holdings, is materially above 45,000 shares.

The 13D/G Layer

The institutional ownership file on UTHR shows passive index thresholds, not activist intervention. The most recent 13G/G filings (CUSIP from the UTHR page):

• Vanguard Capital Management LLC — 5.190%, SC 13G filed 2026-04-30, 2,278,348 shares
• Wellington Management Group LLP — 5.700%, SC 13G filed 2026-02-10, 2,441,492 shares
• United Therapeutics Corp — 5.500% (issuer-level filing), February 2025

No Schedule 13D filings — no investor is publicly arguing for governance or strategic change. The cap-table conversation is between the index complex, Wellington's discretionary book, and the rest of the institutional tail. None of those holders is reacting to a $4.87M scheduled GC sale.

What Comes Next

Three anchors define the next sentinel events:

1. The May 21 / June 4 sessions. If the cadence holds — 8,300 options exercised, 8,300 shares sold — the plan is mechanical and the signal density of each individual Form 4 is low. A skipped session would say the plan was paused or the 10b5-1 framework was amended.
2. Any 10b5-1 plan re-filing. Plans typically run 6-12 months; the underlying SEC filing or proxy disclosure will surface the plan adoption date. A new plan adopted after July 2026 would reset the read.
3. The Q2 2026 earnings cycle. United Therapeutics typically reports Q2 results in late July. Insider trading windows close ahead of earnings, so the absence of Form 4 activity in the four-week pre-print window is normal — not a signal.

The Read

Paul Mahon's three-session, $14.4M April-May exercise-and-sell sequence is the cleanest example of a 10b5-1 plan execution in the current UTHR insider file. The dollar amount is large; the signal density is low. For investors trying to extract a directional view on UTHR from insider activity, the answer is: this particular file gives you very little, and most of what looks like "selling pressure" on the tape is a calendar event. The interesting question is whether Mahon and Rothblatt's plans renew at the next adoption window. That is the read that will move out of the noise.

Track Mahon's complete transaction record, United Therapeutics' full executive selling pattern, and the UTHR institutional holder file at /stocks/UTHR. Cross-reference insider signal flow at /insights.