Summit Partners entity tied to MACOM (MTSI) director sells 43,268 shares

Filing Impact

(Very High)

Filing Sentiment

(Very Negative)

Form Type

Rhea-AI Filing Summary

MACOM Technology Solutions Holdings director-related entity sells shares. An entity associated with director Peter Y. Chung, Summit Partners, L.P., completed an open-market sale of 43,268 shares of MACOM common stock at a weighted average price of $378.1992 per share on May 14, 2026.

According to the disclosures, the remaining 6,781 shares and restricted stock units are held in Mr. Chung’s name for the benefit of Summit Partners, L.P., which, through its investment committee, has voting and dispositive authority and is entitled to the sale proceeds.

Insider Trade Summary

Net Seller: 43,268 shares ($16,363,923)

Net Sell 1 txn

Insider CHUNG PETER Y

Role null

Sold 43,268 shs ($16.36M)

Type	Security	Shares	Price	Value
Sale	Common Stock	43,268	$378.1992	$16.36M

Holdings After Transaction: Common Stock — 6,781 shares (Indirect, See Remarks)

Footnotes (1)

The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $377.80 to $379.44. The Reporting Person undertakes to provide to the Issuer, any shareholder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The 6,781 shares and restricted stock units are held in the name of Mr. Chung, which are held for the benefit of Summit Partners, L.P. Mr. Chung holds any Common Stock and restricted stock units for the benefit of Summit Partners, L.P. which he has empowered to determine when the underlying shares will be sold and which is entitled to the proceeds of any such sales. Summit Partners, L.P., through a two-person Investment Committee, responsible for voting and investment decisions with respect to the Issuer, currently composed of Scott C. Collins and Peter Y. Chung, has voting and dispositive authority over the shares and restricted stock units reported herein and therefore may be deemed to beneficially own such shares. Summit Partners, L.P., Mr. Collins and Mr. Chung disclaim beneficial ownership of the shares of common stock and the restricted stock units, except to the extent of their pecuniary interest therein.

Key Figures

Shares sold: 43,268 shares Weighted average sale price: $378.1992 per share Sale price range: $377.80–$379.44 per share +2 more

5 metrics

Shares sold 43,268 shares Open-market sale of MACOM common stock on May 14, 2026

Weighted average sale price $378.1992 per share Average price for 43,268 MACOM shares sold

Sale price range $377.80–$379.44 per share Multiple transactions within this range

Shares and RSUs remaining 6,781 units Held in Mr. Chung’s name for Summit Partners, L.P.

Net buy/sell direction Net sale of 43,268 shares TransactionSummary shows net-sell for this Form 4

Key Terms

weighted average price, restricted stock units, dispositive authority, beneficial ownership, +1 more

5 terms

weighted average price financial

"The price reported in Column 4 is a weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

restricted stock units financial

"The 6,781 shares and restricted stock units are held in the name of Mr. Chung"

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.

dispositive authority financial

"has voting and dispositive authority over the shares and restricted stock units"

beneficial ownership financial

"may be deemed to beneficially own such shares"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

pecuniary interest financial

"disclaim beneficial ownership ... except to the extent of their pecuniary interest therein"

Form 4 Insider Transactions: What Each Field Means →

05/18/2026 - 04:02 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^*

CHUNG PETER Y

(Last)

(First)

(Middle)

C/O SUMMIT PARTNERS

222 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON

MASSACHUSETTS

02116

(City)

(State)

(Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
MACOM Technology Solutions Holdings, Inc. [ MTSI ]

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

X	Director	10% Owner
	Officer (give title below)	Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/14/2026

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	05/14/2026		S		43,268	D	$378.1992⁽¹⁾	6,781⁽²⁾	I	See Remarks⁽³⁾

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. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $377.80 to $379.44. The Reporting Person undertakes to provide to the Issuer, any shareholder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

2. The 6,781 shares and restricted stock units are held in the name of Mr. Chung, which are held for the benefit of Summit Partners, L.P.

3. Mr. Chung holds any Common Stock and restricted stock units for the benefit of Summit Partners, L.P. which he has empowered to determine when the underlying shares will be sold and which is entitled to the proceeds of any such sales. Summit Partners, L.P., through a two-person Investment Committee, responsible for voting and investment decisions with respect to the Issuer, currently composed of Scott C. Collins and Peter Y. Chung, has voting and dispositive authority over the shares and restricted stock units reported herein and therefore may be deemed to beneficially own such shares. Summit Partners, L.P., Mr. Collins and Mr. Chung disclaim beneficial ownership of the shares of common stock and the restricted stock units, except to the extent of their pecuniary interest therein.

	Adam H. Hennessey, POA for Peter Y. Chung	05/18/2026
	** 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 transaction did MACOM Technology Solutions (MTSI) report?

MACOM Technology Solutions reported an open-market sale of 43,268 common shares linked to director Peter Y. Chung. The sale was executed on May 14, 2026, at a weighted average price of $378.1992 per share, through an entity associated with Summit Partners, L.P.

Who effectively controlled the sold MACOM (MTSI) shares in this Form 4?

The shares were held for the benefit of Summit Partners, L.P., which, through a two-person investment committee, has voting and dispositive authority. The committee, including Peter Y. Chung, determines when MACOM shares and restricted stock units are sold and is entitled to related sale proceeds.

How many MACOM (MTSI) shares were sold and at what price range?

A total of 43,268 MACOM common shares were sold at a weighted average price of $378.1992. The transactions occurred in multiple trades at prices ranging from $377.80 to $379.44 per share, as disclosed in the Form 4 footnotes.

How many MACOM (MTSI) shares and units remain after this insider sale?

After the reported sale, 6,781 MACOM shares and restricted stock units remain held in Peter Y. Chung’s name for the benefit of Summit Partners, L.P. Summit Partners retains voting and investment authority over these securities and any associated economic interest.

Does Peter Y. Chung fully own the MACOM (MTSI) shares in this filing?

The filing states that Mr. Chung, Summit Partners, L.P., and Scott C. Collins may be deemed beneficial owners but disclaim beneficial ownership except for their pecuniary interest. Summit Partners, via its investment committee, has voting and dispositive authority over the MACOM shares and restricted stock units.