FORM 4
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 that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.         
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES
                                                                                  
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OMB Number: 3235-0287
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
                      

1. Name and Address of Reporting Person *

Lin Chih-Hsiang (Thompson)
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
(Last)          (First)          (Middle)

C/O APPLIED OPTOELECTRONICS, INC.
13139 JESS PIRTLE BLVD.
3. Date of Earliest Transaction (MM/DD/YYYY)

5/28/2026
(Street)

SUGAR LAND  TEXAS  77478
4. If Amendment, Date Original Filed (MM/DD/YYYY)

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

_X _ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)        (State)        (Zip/Postal Code)
UNITED STATES
(Country)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Trans. Date 2A. Deemed Execution Date, if any 3. Trans. 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         807,602 I By Lin Family Investment Holdings LLC (1)
Common Stock, $.001 par value         1,448,091 D  
Common Stock, $.001 par value 5/28/2026  G  85,790.27 D$0 (2)807,602 I By Lin Family Investment Holdings LLC (2)
Common Stock, $.001 par value 5/28/2026  G  85,790.27 A$0 (2)85,790.27 I By Thompson Lin Family Trust (4)
Common Stock, $.001 par value 5/28/2026  J  721,811.73 D (3)807,602 I By Lin Family Investment Holdings LLC (3)
Common Stock, $.001 par value 5/28/2026  J  721,811.73 A (3)807,602 I By Thompson Lin Family Trust (4)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security3. Trans. Date3A. Deemed Execution Date, if any4. Trans. Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
6. Date Exercisable and Expiration Date7. 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 of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares

Explanation of Responses:
(1) On May 26, 2026, the reporting person contributed 807,602 directly owned shares of Applied Optoelectronics, Inc. (the "Company")'s common stock to Lin Family Investment Holdings LLC, a Delaware limited liability company (the "LLC"). The reporting person serves as the sole member and the sole manager of the LLC and owned all of the outstanding LLC membership interests directly. In his capacity as the manager of the LLC, he has the sole power to vote and direct the disposition of the shares. Such contribution was exempt from reporting by virtue of Rule 16a-13 because it merely changed the form of beneficial ownership from direct to indirect without affecting the reporting person's pecuniary interest in the shares.
(2) The reported transaction reflects the gift of a portion of the reporting person's membership interest in the LLC, valued at $15 million, as determined by utilizing the average of the high and low per share trading price on the date of the gift (the per share price on the date of the gift, May 28, 2026, was $174.845 and the number of shares was 85,790.27), from the reporting person into an irrevocable trust for the benefit of the reporting person's heirs for estate planning purposes. The LLC continues to hold the 807,602 shares of the Company's common stock, and continues to be managed by the reporting person as the sole manager. This transaction was a bona fide gift to The Thompson Lin Family Trust (the "Family Trust"), and therefore no consideration was paid for the shares. The reporting person disclaims beneficial ownership of these securities except to the extent of his voting power therein.
(3) The reported transaction reflects the transfer of a certain portion of the reporting person's membership interest in the LLC from the reporting person to the Family Trust, in exchange for a promissory note in the principal amount of $126,205,171.69, representing the fair market value of the shares (represented by the portion of the LLC membership interest) as determined by utilizing the average of the high and low per share trading price on the date of the sale. The per share price on the date of the sale, May 28, 2026, was $174.845 and the number of shares sold was 721,811.73. The LLC continues to hold the 807,602 shares of the Company's common stock, and continues to be managed by the reporting person as the sole manager. The reporting person disclaims beneficial ownership of these securities except to the extent of his voting power therein.
(4) The securities indirectly held in the Family Trust through the ownership of interests in the LLC are for the benefit of the reporting person's heirs. The reporting person is the settlor of the irrevocable Family Trust, where The Bryn Mawr Trust Company of Delaware serves as trustee which may be replaced at the discretion of the reporting person. The reporting person disclaims beneficial ownership of these securities except to the extent of his voting power therein, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose.

Reporting Owners
Reporting Owner Name / Address
Relationships
Director10% OwnerOfficerOther
Lin Chih-Hsiang (Thompson)
C/O APPLIED OPTOELECTRONICS, INC.
13139 JESS PIRTLE BLVD.
SUGAR LAND
TEXAS
77478
UNITED STATES
X
President and CEO

Signatures
/s/ David C. Kuo, attorney in fact for Chih-Hsiang (Thompson) Lin6/1/2026
**Signature of Reporting PersonDate


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 control number.
* Form 4: SEC 1474 (03-26).