TMUS: CEO G. Michael Sievert Keeps a Quarterly Selling Cadence as Blocks Drop to 15,000 Shares

TMUS: G. Michael Sievert, CEO of T-Mobile US, has kept up a highly repeatable selling cadence that looks like a pre-planned 10b5-1 style program, not a one-off discretionary exit. The pattern is clear: two-day selling windows each quarter, with 22,500-share blocks through 2025 and a smaller 15,000-share window in February 2026.

What happened in the latest selling cycle

Across the most recent TMUS windows, Sievert sold in tight two-day clusters rather than random dates. The sequence in your transaction set shows a consistent quarterly rhythm, and activity extends into late March 2026 (last transaction date: 2026-03-27 in the prepared insider context).

Date	Code	Shares	Price	Estimated Value
2026-02-24	S	1,089	$221.85	$242K
2026-02-23	S	13,911	$220.07	$3.1M
2025-11-18	S	22,500	$214.25	$4.8M
2025-11-17	S	22,500	$216.97	$4.9M
2025-08-19	S	22,500	$257.17	$5.8M
2025-08-18	S	22,500	$255.58	$5.8M
2025-05-20	S	22,500	$240.99	$5.4M
2025-05-19	S	22,500	$244.40	$5.5M

The key change is sizing: earlier windows were 45,000 shares total (22,500 + 22,500), while February 2026 was 15,000 shares total (13,911 + 1,089). That is still systematic execution, just at a smaller block size.

Price path: same cadence, lower execution levels

Execution prices in the windows above fell from about $257 in August 2025 to about $221 in February 2026. That decline in sale price does not, by itself, invalidate the cadence; it simply shows the same program running in a different price regime.

Third-party market coverage has also described mixed TMUS performance in early 2026, including pullbacks and short rebounds, which fits the idea that systematic plans can keep running through volatility rather than trying to time tops and bottoms: Reuters on T-Mobile's February update, TIKR 2026 TMUS performance note.

Company backdrop from earnings season

T-Mobile's own Q4 2025 release highlighted strong customer additions and profitability expansion, and management paired results with forward commentary at its investor event. That backdrop matters because pre-planned selling programs often continue regardless of whether a quarter is operationally strong or weak.

• T-Mobile Q4 2025 earnings release
• T-Mobile earnings call and Capital Markets Day page
• Yahoo Finance recap on Q4 beat

Key facts for Sievert's insider pattern

Insider	G. Michael Sievert
Company	T-Mobile US (TMUS)
Career buys	$0
Career sells	$176.7M
Total transactions	155
Shares remaining	125,695
Signal type	Systematic insider sell cadence (10b5-1 style)

Importantly, this is not the same as saying management is "calling a top." A repeated, scheduled disposition pattern is usually a liquidity/planning mechanism. The informational edge is in changes to cadence, block size, or cancellation, not the mere existence of sales.

Cross-market context and what to watch next

For relative telecom context, compare trading and ownership behavior across peers such as AT&T, Verizon, Charter, and Comcast. On the ownership side of TMUS itself, large holders include Vanguard, BlackRock, SoftBank Group, and State Street.

• Window timing: whether the next TMUS sale again lands in a tight two-day cluster.
• Block size: whether the newer 15,000-share level persists or reverts toward prior 45,000-share quarterly windows.
• Execution band: whether future sales clear closer to the $220 range or recover toward the mid-$250s seen in 2025.
• Institutional base: whether top TMUS holders materially add, trim, or stay stable around upcoming 13F cycles.
• Fundamental cadence: whether subscriber and margin commentary from management continues to support the operating narrative while sales remain systematic.