Onto Innovation

Nonqualified Deferred Compensation Plan

Adoption Agreement

Effective as of January 1, 2026

Table of Contents

1.01 Preamble

By the execution of this Adoption Agreement the Plan Sponsor hereby [complete (a) or (b)]

(a) ☒ adopts a new plan as of January 1, 2026

(b) ☐ amends and restates its existing plan as of [month, day, year] which is the Amendment Effective Date. Except as otherwise provided in Appendix A, all amounts deferred under the Plan prior to the Amendment Effective Date shall be governed by the terms of the Plan as in effect on the day before the Amendment Effective Date.

Original Effective Date: [month, day, year]

Pre-409A Grandfathering: ☐ Yes ☐ No

By executing this Adoption Agreement, the Plan Sponsor (as defined below) has adopted the Plan (as defined below) consisting of the Basic Plan Document along with this Adoption Agreement (and any exhibits or schedules attached hereto). The Plan Sponsor, by completing this Adoption Agreement has made the specific choices regarding plan design as set forth in the Adoption Agreement together with the detailed additional provisions set out in the Basic Plan Document. All capitalized terms used in this Adoption Agreement have the same meaning given in the Basic Plan Document.

1.02 Plan

1.03 Plan Sponsor

Is stock of the Plan Sponsor, any Employer or any Related Employer publicly traded on an established securities market? ☒ Yes ☐ No

1.04 Employer

The following entities have been authorized by the Plan Sponsor to participate in and have adopted the Plan [insert “Not Applicable” if none have been authorized]:

1.05 Administrator

The Plan Sponsor has designated the following party or parties to be responsible for the administration of the Plan:

1.06 Key Employee Determination Dates

The Employer has designated December 31 as the Identification Date for purposes of determining Key Employees.

In the absence of a designation, the Identification Date is December 31.

The Employer has designated April 1 as the effective date for purposes of applying the
six-month delay in distributions to Key Employees.

In the absence of a designation, the effective date is the first day of the fourth month following the Identification Date.

2.01 Participation

(a) ☒ Employees [complete (i), (ii) or (iii)]

(i) ☒ Eligible Employees are selected by the Employer.

(ii) ☐ Eligible Employees are those employees of the Employer who satisfy the following criteria:

(iii) ☐ Employees are not eligible to participate.

(b) ☒ Directors [complete (i), (ii) or (iii)]

(i) ☐ All Directors are eligible to participate.

(ii) ☒ Only Directors selected by the Employer are eligible to participate.

(ii) ☐ Directors are not eligible to participate.

3.01 Compensation

For purposes of determining Participant contributions under Article 4 and Employer contributions under Article 5, Compensation shall be defined in the following manner [complete (a) or (b) and select (c) and/or (d), if applicable]:

(a) ☒ Compensation is defined as:

(b) ☐ Compensation as defined in [insert name of qualified plan] without regard to the limitation in Section 401(a)(17) of the Code for such Plan Year.

(c) ☒ Director Compensation is defined as:

(d) ☐ Compensation shall, for all Plan purposes, be limited to $ .

(e) ☐ Not Applicable.

3.02 Bonuses

Compensation, as defined in Section 3.01 of the Adoption Agreement, includes the following type of bonuses that will be the subject of a separate deferral election:

4.01 Participant Contributions

If Participant contributions are permitted, complete (a) and (b). Otherwise complete (c).

(a) Amount of Deferrals

A Participant may elect within the period specified in Section 4.01(b) of the Adoption Agreement to defer the following amounts of remuneration. For each type of remuneration listed, complete “dollar amount” and/or “percentage amount”.

(i) Compensation other than Bonuses [do not complete if you complete (iii)]

Note: The increment is required to determine the permissible deferral amounts. For example, a minimum of 0% and maximum of 20% with a 5% increment would allow an individual to defer 0%, 5%, 10%, 15% or 20%.

(ii) Bonuses [do not complete if you complete (iii)]

(iii) Compensation [do not complete if you completed (i) and (ii)]

(iv) Director Compensation

(b) Election Period

(i) Performance Based Compensation

A special election period

apply to each eligible type of performance based compensation referenced in Section 3.02 of the Adoption Agreement.

The special election period, if applicable, will be determined by the Employer.

(ii) Newly Eligible Participants

An employee who is classified or designated as an Eligible Employee during a Plan Year

elect to defer Compensation earned during the remainder of the Plan Year by completing a deferral agreement within the 30-day period beginning on the date he or she is eligible to participate in the Plan.

The special election period, if applicable, will be determined by the Employer.

(c) No Participant Contributions

5.01 Employer Contributions

If Employer contributions are permitted, complete (a) and/or (b). Otherwise complete (c).

(a) Matching Contributions

(i) Amount

For each Plan Year, the Employer shall make a matching contribution on behalf of each Participant who defers Compensation for the Plan Year and satisfies the requirements of Section 5.01(a)(ii) of the Adoption Agreement equal to [complete the ones that are applicable]:

(A) ☐ [insert percentage]% of the Compensation the Participant has elected to defer for the Plan Year

(B) ☐ An amount determined by the Employer in its sole discretion

(C) ☐ Matching contributions for each Participant shall be limited to $ and/or [insert percentage]% of Compensation

(D) ☐ Other:

(E) ☒ Not Applicable [Proceed to Section 5.01(b)]

(ii) Eligibility for matching contribution

A Participant who defers Compensation for the Plan Year shall receive an allocation of matching contributions determined in accordance with Section 5.01(a)(i) provided he or she satisfies the following requirements [complete the ones that are applicable]:

(A) ☐ Describe requirements:

(B) ☐ Is selected by the Employer in its sole discretion to receive an allocation of matching contributions

(C) ☐ No requirements

(iii) Time of Allocation

Matching contributions, if made, shall be treated as allocated [select one]:

(A) ☐ As of the last day of the Plan Year

(B) ☐ At such times as the Employer shall determine in its sole discretion

(C) ☐ At the time the Compensation on account of which the matching contribution is being made would otherwise have been paid to the Participant

(D) ☐ Other:

(b) Other Contributions

(i) Amount

The Employer shall make a contribution on behalf of each Participant who satisfies the requirements of Section 5.01(b)(ii) equal to [complete the ones that are applicable]:

(A) ☐ An amount equal to [insert percentage]% of the Participant’s Compensation

(B) ☒ An amount determined by the Employer in its sole discretion

(C) ☐ Contributions for each Participant shall be limited to $

(D) ☐ Other:

(E) ☐ Not Applicable [Proceed to Section 6.01]

(ii) Eligibility for Other Contribution

A Participant shall receive an allocation of other Employer contributions determined in accordance with Section 5.01(b)(i) for the Plan Year if he

or she satisfies the following requirements [complete the one that is applicable]:

(A) ☐ Describe requirements:

(B) ☒ Is selected by the Employer in its sole discretion to receive an allocation of other Employer contributions

(C) ☐ No requirements

(iii) Time of Allocation

Employer contributions, if made, shall be treated as allocated [select one]:

(A) ☐ As of the last day of the Plan Year

(B) ☒ At such times or times as the Employer shall determine in its sole discretion

(C) ☐ Other:

(c) No Employer Contributions

6.01 Distributions

The timing and form of payment of distributions made from the Participant’s vested Account shall be made in accordance with the elections made in this Section 6.01 of the Adoption Agreement except when Section 9.6 of the Plan requires a six-month delay for certain distributions to Key Employees of publicly traded companies.

(a) Timing of Distributions

(i) All distributions shall commence in accordance with the following [choose one]:

(A) ☒ As soon as administratively feasible following the distribution event but in no event later than the time prescribed by Treas. Reg. Sec. 1.409A-3(d).

(B) ☐ Monthly on specified day [insert day]

(C) ☐ Annually on specified month and day [insert month and day]

(D) ☐ Calendar quarter on specified month and day [insert month and day] [insert numerical quarter 1, 2, 3, or 4]

(ii) The timing of distributions as determined in Section 6.01(a)(i) shall be modified by the adoption of:

(A) ☒ Event Delay – Distribution events other than those based on Specified Date, Death, Disability or Change in Control will be treated as not having occurred for six (6) months

(B) ☐ Hold Until Next Year – Distribution events other than those based on Specified Date or Specified Age will be treated as not having occurred for twelve months from the date of the event if payment pursuant to Section 6.01(a)(i) will thereby occur in the next calendar year or on the first payment date in the next calendar year in all other cases

(C) ☐ Immediate Processing – The timing method selected by the Plan Sponsor under Section 6.01(a)(i) shall be overridden for the following distribution events [insert events]:

(D) ☐ Not applicable

(b) Distribution Events

(i) Participant Contributions under Section 4.01(a)

Participants may elect the following payment events and the associated form or forms of payment. If multiple events for each year are selected, the earliest to occur will trigger payment. For installments, insert the range of available periods (e.g., 5-15) or insert the periods available (e.g., 5, 7, 9).

The minimum deferral period for Specified Date or Specified Age event shall be two (2) years, except the minimum deferral period in the case of a Restricted Stock Unit or Performance Share Unit shall be three (3) years.

Installments may be paid [select each that applies]

(ii) Employer Contributions under Section 5.01(a) and (b)

Participants may elect the following payment events and the associated form or forms of payment. If multiple events for each year are selected, the earliest to occur will trigger payment. For installments, insert the range of available periods (e.g., 5-15) or insert the periods available (e.g., 5, 7, 9).

The minimum deferral period for Specified Date or Specified Age event shall be Not Applicable years.

Installments may be paid [select each that applies]

(c) Specified Date and Specified Age elections may not extend beyond age Not Applicable.

(d) Payment Election Override

Payment of the remaining vested balance of the Participant’s Account will automatically occur at the time specified in Section 6.01(a) of the Adoption Agreement in the form indicated upon the earliest to occur of the following events [check each event that applies and for each event include only a single form of payment]:

(e) Involuntary Cashouts

(f) Retirement

(g) Distribution Election Change

A Participant

be permitted to modify a scheduled distribution date and/or payment option in accordance with Section 9.2 of the Plan.

A Participant shall generally be permitted to elect such modification _two (2)_ number of times.

Administratively, allowable distribution events will be modified to reflect all options necessary to fulfill the distribution change election provision.

(h) Frequency of Elections

The Plan Sponsor

elected to permit annual elections of a time and form of payment for amounts deferred under the Plan. If a single election of a time and/or form of payment is required, the Participant will make such election at the time he or she first completes a deferral agreement which, in all cases, will be no later than the time required by Reg. Sec. 1.409A-2.

(i) Disability

For Purposes of Section 2.11 of the Plan, Disability shall be defined as

7.01 Vesting

(a) Matching Contributions

The Participant’s vested interest in the amount credited to his or her Account attributable to matching contributions shall be based on the following schedule:

☐

(b) Other Employer Contributions

The Participant’s vested interest in the amount credited to his or her Account attributable to Employer contributions other than matching contributions shall be based on the following schedule:

☒

(c) Acceleration of Vesting

The Participant’s vested interest in his or her Account will automatically be 100% upon the occurrence of the following events [select the ones that are applicable]:

(vi) ☒ Not applicable.

(d) Years of Service

(i) A Participant’s Years of Service shall include all service performed for the Employer and

include service performed for the Related Employer.

(ii) Years of Service shall also include service performed for the following entities:

(iii) Years of Service shall be determined in accordance with [select one]:

(A) ☐ The elapsed time method in Treas. Reg. Sec. 1.410(a)-7

(B) ☐ The general method in DOL Reg. Sec. 2530.200b-1 through b-4

(C) ☐ Participant’s Years of Service credited under:

(D) ☐ Other:

(iv) ☒ Not applicable.

8.01 Unforeseeable Emergency

(a) A withdrawal due to an Unforeseeable Emergency as defined in Section 2.24:

be allowed.

(b) Upon a withdrawal due to an Unforeseeable Emergency, a Participant’s deferral election for the remainder of the Plan Year:

be cancelled. If cancellation occurs, the Participant may resume participation in accordance with Article 4 of the Plan.

9.01 Investment Decisions

Investment decisions regarding the hypothetical amounts credited to a Participant’s Account shall be made by [select one]:

10.01 Trust

The Employer [select one]:

intend to establish a trust as provided in Article 11 of the Plan.

11.01 Termination Upon Change In Control

The Plan Sponsor

the right to terminate the Plan and distribute all vested amounts credited to Participant Accounts upon a Change in Control as described in Section 9.7.

11.02 Automatic Distribution Upon Change In Control

Distribution of the remaining vested balance of each Participant’s Account

automatically be paid as a lump sum payment upon the occurrence of a Change in Control as provided in Section 9.7.

11.03 Change In Control

A Change in Control for Plan purposes includes the following [select each definition that applies]:

12.01 Governing State Law

The laws of Delaware shall apply in the administration of the Plan to the extent not preempted by ERISA.

The Plan Sponsor has caused this Adoption Agreement to be executed this 19th day of
November , 2025 .

Appendix A

Special Effective Dates

Not Applicable