Matthew Tappin - 30 Jun 2026 Form 4 Insider Report for STEM, INC. (STEM)

Reporting relationship: President, Software Products
Issuer ticker: STEM
Reported as of: 30 Jun 2026
Net transaction value: -$7,819
SEC form: 4
Accepted by SEC: 02 Jul 2026, 18:57:07 UTC
Prior SEC filing: 13 Mar 2026
Source filing: View source filing
Reporting owner signature: /s/ Sarah Dunn, attorney-in-fact

Key filing fact

Matthew Tappin filed Form 4 for STEM, INC. (STEM) on 02 Jul 2026.

Key facts

This page summarizes Matthew Tappin's Form 4 filing for STEM, INC. (STEM).
5 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 02 Jul 2026, 18:57.

Change

Previous filing in this sequence was filed on 13 Mar 2026.
Current net transaction value: -$7,819.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001986259 Primary reporting owner

Tappin Matthew

Relationship: President, Software Products
Address: 1400 POST OAK BOULEVARD, SUITE 560, HOUSTON
Signature: /s/ Sarah Dunn, attorney-in-fact
Signature date: 02 Jul 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

STEM transaction

Common Stock, Par Value $0.0001 Per Share

Options Exercise

Transaction value
Shares: +5,000
Change %: +177%
Price: $7.81^*
Shares after: 7,823
Date: 30 Jun 2026
Ownership: Direct

STEM transaction

Common Stock, Par Value $0.0001 Per Share

Options Exercise

Transaction value
Shares: +2,750
Change %: +35%
Price: $7.81^*
Shares after: 10,573
Date: 30 Jun 2026
Ownership: Direct

STEM transaction

Common Stock, Par Value $0.0001 Per Share

Sale

Transaction value: $7,819
Shares: -996
Change %: -9.4%
Price: $7.85
Shares after: 9,577
Date: 02 Jul 2026
Ownership: Direct
Footnotes: F1

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

STEM transaction Derivative

Performance Stock Unit

Options Exercise

Transaction value
Shares: -2,750
Change %: -50%
Price: $0.000000^*
Shares after: 2,750
Date: 30 Jun 2026
Ownership: Direct
Underlying class: Common Stock, Par Value $0.0001 Per Share
Underlying amount: 2,750
Exercise price
Footnotes: F2, F3

STEM transaction Derivative

Performance Stock Unit

Options Exercise

Transaction value
Shares: -5,000
Change %: -50%
Price: $0.000000^*
Shares after: 5,000
Date: 30 Jun 2026
Ownership: Direct
Underlying class: Common Stock, Par Value $0.0001 Per Share
Underlying amount: 5,000
Exercise price
Footnotes: F2, F4

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 4 footnotes

Footnote F1

Represents shares of common stock automatically sold to cover the reporting person's tax liability in connection with the settlement of PSUs on June 30, 2026. This "sell to cover" transaction does not represent a discretionary trade by the reporting person.

Footnote F2

Each performance stock unit ("PSU") represented a contingent right to receive one share of the Issuer's common stock if the volume-weighted average price of the Issuer's common stock for any consecutive sixty (60) trading-day period equaled or exceeded $17.60 (the "Performance Metric") during a performance period ending on June 30, 2028 (the "Performance Period").

Footnote F3

On June 30, 2025, the Reporting Person was granted 5,500 PSUs, 2,750 of which vested on June 30, 2026 following the Issuer's achievement of the Performance Metric during the Performance Period.

Footnote F4

On July 28, 2025, the Reporting Person was granted 10,000 PSUs, 5,000 of which vested on June 30, 2026 following the Issuer's achievement of the Performance Metric during the Performance Period.