[Form 4] Applied Optoelectronics, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Chih-Hsiang (Thompson) Lin, President, CEO and a director of Applied Optoelectronics, Inc. (AAOI), reported purchases of company common stock on 08/14/2025. Mr. Lin acquired 5,750 shares indirectly through a 401(k) plan at a weighted-average price of $21.62, 1,405 shares directly at a weighted-average price of $21.26, and 920 shares directly at a weighted-average price of $21.60, increasing his reported beneficial ownership to 1,663,490 shares. The trades were disclosed on Form 4 filed 08/15/2025 and the filing was signed by David C. Kuo as attorney-in-fact.

Insights

Financial Analyst

Insider purchases by the CEO signal modest confidence but are not large enough alone to alter valuation.

The Form 4 shows Mr. Lin added 8,075 shares across three purchase groupings on 08/14/2025 at weighted-average prices roughly between $21.26 and $21.62. Insider buying by a CEO is generally viewed positively because it aligns management and shareholder interests, but the absolute size of these transactions relative to total outstanding shares is small. These are routine open-market and 401(k)-based purchases rather than large, strategic buys or acquisitions, so the market impact is likely limited absent other news.

Corporate Governance Expert

Disclosure is timely and standard; purchases include indirect 401(k) allocations which is common for executives.

The filer identified both direct and indirect ownership and provided weighted-average prices and an undertaking to supply per-price details if requested, meeting disclosure norms. The filing was signed by an attorney-in-fact, which is acceptable when properly authorized. No option exercises, sales, or other governance concerns are reported. The transaction appears routine and compliant with Section 16 reporting requirements.

Insider Trade Summary

Net Buyer: 8,075 shares ($174,057)

Net Buy 3 txns

Insider Lin Chih-Hsiang (Thompson)

Role President and CEO

Bought 8,075 shs ($174K)

Type	Security	Shares	Price	Value
Purchase	Common Stock, $.001 par value	5,750	$21.62	$124K
Purchase	Common Stock, $.001 par value	1,405	$21.26	$30K
Purchase	Common Stock, $.001 par value	920	$21.60	$20K

Holdings After Transaction: Common Stock, $.001 par value — 1,661,165 shares (Indirect, By 401(k)); Common Stock, $.001 par value — 1,662,570 shares (Direct)

Footnotes (1)

1. These shares were purchased through 401(k) in multiple transactions on August 14, 2025 at prices ranging from $20.75 to $22.90 per share. The price reported reflects the weighted average purchase prices for the transactions. The reporting person undertakes to provide, upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares purchased at each separate price. These shares were purchased in multiple transactions on August 14, 2025 at prices ranging from $21.11 to $21.40 per share. The price reported reflects the weighted average purchase prices for the transactions. The reporting person undertakes to provide, upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares purchased at each separate price. These shares were purchased in multiple transactions on August 14, 2025 at prices ranging from $21.54 to $21.65 per share. The price reported reflects the weighted average purchase prices for the transactions. The reporting person undertakes to provide, upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares purchased at each separate price.

Form 4 Insider Transactions: What Each Field Means →

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^*

Lin Chih-Hsiang (Thompson)

(Last) (First) (Middle)

C/O APPLIED OPTOELECTRONICS, INC.

13139 JESS PIRTLE BLVD.

(Street)

SUGAR LAND TX 77478

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
APPLIED OPTOELECTRONICS, INC. [ AAOI ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
08/14/2025

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

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

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

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)
			Code	V	Amount	(A) or (D)	Price
Common Stock, $.001 par value	08/14/2025		P		5,750(1)	A	$21.62	1,661,165	I	By 401(k)
Common Stock, $.001 par value	08/14/2025		P		1,405(2)	A	$21.26	1,662,570	D
Common Stock, $.001 par value	08/14/2025		P		920(3)	A	$21.6	1,663,490	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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. These shares were purchased through 401(k) in multiple transactions on August 14, 2025 at prices ranging from $20.75 to $22.90 per share. The price reported reflects the weighted average purchase prices for the transactions. The reporting person undertakes to provide, upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares purchased at each separate price.

2. These shares were purchased in multiple transactions on August 14, 2025 at prices ranging from $21.11 to $21.40 per share. The price reported reflects the weighted average purchase prices for the transactions. The reporting person undertakes to provide, upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares purchased at each separate price.

3. These shares were purchased in multiple transactions on August 14, 2025 at prices ranging from $21.54 to $21.65 per share. The price reported reflects the weighted average purchase prices for the transactions. The reporting person undertakes to provide, upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares purchased at each separate price.

	/s/ David C. Kuo, attorney in fact for Chih-Hsiang (Thompson) Lin	08/15/2025
	** 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.
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