Were Regan Mills’ Teradyne (TER) share sales made under a Rule 10b5-1 plan?

Yes. The Form 4 footnote states that the 252-share sale on April 2, 2026 was executed under a sales plan adopted on November 25, 2025 and intended to comply with Rule 10b5-1 under the Securities Exchange Act.

Teradyne (TER) executive logs small 10b5-1 share sale and tax withholding

Filing Impact

(High)

Filing Sentiment

(Negative)

Form Type

Rhea-AI Filing Summary

Teradyne, Inc. executive Regan Mills reported small share sales and tax-related share withholding. On April 2, 2026, Mills completed an open-market sale of 252 shares of common stock at $290.88 per share, and continued to hold 11,415.3452 shares directly afterward.

On April 1, 2026, 222 shares were disposed of to cover tax withholding obligations tied to vesting of restricted stock units, at a value of $312.20 per share. The April 2 sale was made under a pre-established Rule 10b5-1 trading plan adopted on November 25, 2025, indicating the transaction timing was pre-planned.

Insights

Small, pre-planned sale and tax withholding; routine activity.

Teradyne executive Regan Mills, President of Product Test, reported two non-derivative common stock transactions. On April 1, 2026, 222 shares were disposed of to satisfy tax withholding obligations related to vesting restricted stock units, a mechanical step rather than a market trade.

On April 2, 2026, Mills executed an open-market sale of 252 shares at $290.88 per share under a pre-arranged Rule 10b5-1 trading plan adopted on November 25, 2025. Following these events, Mills held 11,415.3452 shares directly, suggesting these were routine, small-scale transactions relative to the overall position.

Insider Trade Summary 10b5-1

Net Seller: 252 shares ($73,302)

Net Sell 2 txns

Insider Mills Regan

Role President, Product Test

Sold 252 shs ($73K)

Type	Security	Shares	Price	Value
Sale	Common Stock	252	$290.88	$73K
Tax Withholding	Common Stock	222	$312.20	$69K

Holdings After Transaction: Common Stock — 11,415.345 shares (Direct)

Footnotes (1)

Shares withheld by the Issuer to satisfy the Reporting Person's tax withholding obligations in connection with the vesting of restricted stock units on April 1, 2026. The shares were sold pursuant to a sales plan adopted by the Reporting Person on November 25, 2025 and intended to comply with Rule 10b5-1 under the Securities Exchange Act of 1934.

Key Figures

Open-market sale: 252 shares at $290.88 Tax withholding shares: 222 shares at $312.20 Post-transaction holdings: 11,415.3452 shares +1 more

4 metrics

Open-market sale 252 shares at $290.88 Common stock sale on April 2, 2026

Tax withholding shares 222 shares at $312.20 Tax-withholding disposition on April 1, 2026

Post-transaction holdings 11,415.3452 shares Direct ownership after April 2, 2026 sale

Net open-market change 252 shares sold Net buy/sell shares across reported transactions

Key Terms

restricted stock units, tax withholding obligations, Rule 10b5-1, open-market sale, +1 more

5 terms

restricted stock units financial

"in connection with the vesting of restricted stock units on April 1, 2026"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

tax withholding obligations financial

"Shares withheld by the Issuer to satisfy the Reporting Person's tax withholding obligations"

Rule 10b5-1 regulatory

"intended to comply with Rule 10b5-1 under the Securities Exchange Act of 1934"

Rule 10b5-1 is a regulation that allows company insiders to buy or sell their shares at predetermined times, even if they have access to non-public information. It acts like setting a schedule in advance for transactions, helping prevent accusations of unfair trading. This rule provides a way for insiders to plan trades transparently, giving investors confidence that these transactions are not based on hidden information.

open-market sale financial

"transaction_action": "open-market sale""

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

tax-withholding disposition financial

"transaction_action": "tax-withholding disposition""

A tax-withholding disposition is an event or transaction—such as selling or transferring securities, exercising options, or receiving compensation—that triggers a requirement to hold back part of the payment and remit it to tax authorities. It matters to investors because it reduces the cash they receive immediately and can change the timing and amount of taxable income, like a cashier taking a portion of your sale proceeds to pay taxes before you get the rest.

Form 4 Insider Transactions: What Each Field Means →

04/03/2026 - 02:52 PM

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Mills Regan

(Last)

(First)

(Middle)

C/O TERADYNE, INC.

600 RIVERPARK DRIVE

(Street)

NORTH READING

MASSACHUSETTS

01864

(City)

(State)

(Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
TERADYNE, INC [ TER ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	President, Product Test

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/01/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	04/01/2026		F		222⁽¹⁾	D	$312.2	11,667.3452	D
Common Stock	04/02/2026		S⁽²⁾		252	D	$290.88	11,415.3452	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. Shares withheld by the Issuer to satisfy the Reporting Person's tax withholding obligations in connection with the vesting of restricted stock units on April 1, 2026.

2. The shares were sold pursuant to a sales plan adopted by the Reporting Person on November 25, 2025 and intended to comply with Rule 10b5-1 under the Securities Exchange Act of 1934.

	/s/ Ryan E. Driscoll, Attorney-in-Fact	04/03/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transactions did Teradyne (TER) executive Regan Mills report?

Regan Mills reported two transactions in Teradyne common stock: a 252-share open-market sale on April 2, 2026 at $290.88 per share and a 222-share tax-withholding disposition on April 1, 2026 related to vesting restricted stock units.

How many Teradyne (TER) shares did Regan Mills sell on the open market?

Regan Mills sold 252 shares of Teradyne common stock in an open-market transaction on April 2, 2026, at a price of $290.88 per share, according to the Form 4 insider filing data provided.

Why were 222 Teradyne (TER) shares disposed of by Regan Mills on April 1, 2026?

The 222-share disposition on April 1, 2026 was to satisfy Regan Mills’ tax withholding obligations arising from the vesting of restricted stock units, meaning the shares were withheld by Teradyne instead of being sold in the open market.

How many Teradyne (TER) shares does Regan Mills hold after these transactions?

After the reported transactions, Regan Mills directly held 11,415.3452 shares of Teradyne common stock, as shown in the post-transaction ownership figure for the April 2, 2026 open-market sale entry in the Form 4 data.

Do these Teradyne (TER) insider transactions indicate large selling by Regan Mills?

No. The transactions involve relatively small share counts: 252 shares sold in the open market and 222 shares withheld for taxes, while Mills still holds 11,415.3452 shares, indicating routine activity rather than a large reduction in ownership.