Sean Chihhsiang Chen sold $772K of Ambiq Micro stock

By AlphaYouPublished Oct 16, 2026Form 4

Stocks in this disclosure

Reported activity

Chen Sean Chihhsiang

Reporting filer

Sean Chihhsiang Chen reported selling 15,000 shares of Ambiq Micro, Inc. for about $772K ($51.50 a share on average). Form 4 filed Oct 16, 2026 lists 7 entries.

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Disclosed: Oct 16, 2026

Reported details

7 entries

All validated entries in this disclosure
Security	Owner	Date	Code	Action	Quantity	Price	Following holdings	Reporting delay	Filed terms and references
Common Stock	Chen Sean Chihhsiang	2026-10-14	M	Exercise or conversion	15000	8.12	121,268	2 days	Filed terms security Title: Common Stock transaction Date: 2026-10-14 transaction Form Type: 4 transaction Code: M equity Swap Involved: 0 id: F1 transaction Shares: 15000 transaction Price Per Share: 8.12 transaction Acquired Disposed Code: A shares Owned Following Transaction: 121268 direct Or Indirect Ownership: D nature Of Ownership:
Common Stock	Chen Sean Chihhsiang	2026-10-14	S	Sale	7539	50.129	113,729	2 days	Filed terms security Title: Common Stock transaction Date: 2026-10-14 transaction Form Type: 4 transaction Code: S equity Swap Involved: 0 id: F1 transaction Shares: 7539 transaction Price Per Share: 50.129 id: F2 transaction Acquired Disposed Code: D shares Owned Following Transaction: 113729 direct Or Indirect Ownership: D nature Of Ownership:
Common Stock	Chen Sean Chihhsiang	2026-10-14	S	Sale	1261	51.5306	112,468	2 days	Filed terms security Title: Common Stock transaction Date: 2026-10-14 transaction Form Type: 4 transaction Code: S equity Swap Involved: 0 id: F1 transaction Shares: 1261 transaction Price Per Share: 51.5306 id: F3 transaction Acquired Disposed Code: D shares Owned Following Transaction: 112468 direct Or Indirect Ownership: D nature Of Ownership:
Common Stock	Chen Sean Chihhsiang	2026-10-14	S	Sale	2000	52.4682	110,468	2 days	Filed terms security Title: Common Stock transaction Date: 2026-10-14 transaction Form Type: 4 transaction Code: S equity Swap Involved: 0 id: F1 transaction Shares: 2000 transaction Price Per Share: 52.4682 id: F4 transaction Acquired Disposed Code: D shares Owned Following Transaction: 110468 direct Or Indirect Ownership: D nature Of Ownership:
Common Stock	Chen Sean Chihhsiang	2026-10-14	S	Sale	4000	53.4363	106,468	2 days	Filed terms security Title: Common Stock transaction Date: 2026-10-14 transaction Form Type: 4 transaction Code: S equity Swap Involved: 0 id: F1 transaction Shares: 4000 transaction Price Per Share: 53.4363 id: F5 transaction Acquired Disposed Code: D shares Owned Following Transaction: 106468 direct Or Indirect Ownership: D nature Of Ownership:
Common Stock	Chen Sean Chihhsiang	2026-10-14	S	Sale	200	54.27	106,268	2 days	Filed terms security Title: Common Stock transaction Date: 2026-10-14 transaction Form Type: 4 transaction Code: S equity Swap Involved: 0 id: F1 transaction Shares: 200 transaction Price Per Share: 54.27 transaction Acquired Disposed Code: D shares Owned Following Transaction: 106268 direct Or Indirect Ownership: D nature Of Ownership:
Stock Option (Right to Buy) (derivative)	Chen Sean Chihhsiang	2026-10-14	M	Exercise or conversion	15000	0	119,423	2 days	Filed terms security Title: Stock Option (Right to Buy) conversion Or Exercise Price: 8.12 transaction Date: 2026-10-14 transaction Form Type: 4 transaction Code: M equity Swap Involved: 0 id: F1 transaction Shares: 15000 transaction Price Per Share: 0 transaction Acquired Disposed Code: D id: F6 expiration Date: 2029-02-20 underlying Security Title: Common Stock underlying Security Shares: 15000 shares Owned Following Transaction: 119423 direct Or Indirect Ownership: D nature Of Ownership:

Common Stock

Owner: Chen Sean Chihhsiang
Date: 2026-10-14
Code: M
Action: Exercise or conversion
Quantity: 15000
Price: 8.12
Following holdings: 121,268
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: M
equity Swap Involved: 0
id: F1
transaction Shares: 15000
transaction Price Per Share: 8.12
transaction Acquired Disposed Code: A
shares Owned Following Transaction: 121268
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Owner: Chen Sean Chihhsiang
Date: 2026-10-14
Code: S
Action: Sale
Quantity: 7539
Price: 50.129
Following holdings: 113,729
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 7539
transaction Price Per Share: 50.129
id: F2
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 113729
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Owner: Chen Sean Chihhsiang
Date: 2026-10-14
Code: S
Action: Sale
Quantity: 1261
Price: 51.5306
Following holdings: 112,468
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 1261
transaction Price Per Share: 51.5306
id: F3
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 112468
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Owner: Chen Sean Chihhsiang
Date: 2026-10-14
Code: S
Action: Sale
Quantity: 2000
Price: 52.4682
Following holdings: 110,468
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 2000
transaction Price Per Share: 52.4682
id: F4
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 110468
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Owner: Chen Sean Chihhsiang
Date: 2026-10-14
Code: S
Action: Sale
Quantity: 4000
Price: 53.4363
Following holdings: 106,468
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 4000
transaction Price Per Share: 53.4363
id: F5
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 106468
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Owner: Chen Sean Chihhsiang
Date: 2026-10-14
Code: S
Action: Sale
Quantity: 200
Price: 54.27
Following holdings: 106,268
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 200
transaction Price Per Share: 54.27
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 106268
direct Or Indirect Ownership: D
nature Of Ownership:

Stock Option (Right to Buy) (derivative)

Owner: Chen Sean Chihhsiang
Date: 2026-10-14
Code: M
Action: Exercise or conversion
Quantity: 15000
Price: 0
Following holdings: 119,423
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Stock Option (Right to Buy)
conversion Or Exercise Price: 8.12
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: M
equity Swap Involved: 0
id: F1
transaction Shares: 15000
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F6
expiration Date: 2029-02-20
underlying Security Title: Common Stock
underlying Security Shares: 15000
shares Owned Following Transaction: 119423
direct Or Indirect Ownership: D
nature Of Ownership:

Purchases, sales, grants and option exercises are different transactions. The reported code identifies the action; it does not establish a motive.

Filing context

Quantities and prices are shown in the units filed. No trade value is inferred from their product.
Chen Sean Chihhsiang: President and COO.
The filing reports a Rule 10b5-1 trading plan.
F1: The transactions reported in this Form 4 occurred under a Rule 10b5-1 plan adopted by the Reporting Person on June 5, 2026
F2: The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $50.00 to $50.98 per share. The Reporting Person undertakes to provide to the Issuer, any security holder 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.
F3: The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $51.00 to $51.90 per share. The Reporting Person undertakes to provide to the Issuer, any security holder 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.
F4: The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $52.02 to $53.01 per share. The Reporting Person undertakes to provide to the Issuer, any security holder 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.
F5: The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $53.04 to $53.91 per share. The Reporting Person undertakes to provide to the Issuer, any security holder 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.
F6: 1/4 of the shares subject to the option vested on February 21, 2020, and 1/48 of the shares subject to the option vested in equal monthly installments thereafter, subject to the Reporting Person's continued service.

Original sources

SEC ownership filing

Prepared automatically from public filing data. Report a correction.

Security

Owner

Date

Code

Action

Quantity

Price

Following holdings

Reporting delay

Filed terms and references

Common Stock

Chen Sean Chihhsiang

2026-10-14

Exercise or conversion

15000

8.12

121,268

2 days

Filed terms

security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: M
equity Swap Involved: 0
id: F1
transaction Shares: 15000
transaction Price Per Share: 8.12
transaction Acquired Disposed Code: A
shares Owned Following Transaction: 121268
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Chen Sean Chihhsiang

2026-10-14

Sale

7539

50.129

113,729

2 days

Filed terms

security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 7539
transaction Price Per Share: 50.129
id: F2
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 113729
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Chen Sean Chihhsiang

2026-10-14

Sale

1261

51.5306

112,468

2 days

Filed terms

security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 1261
transaction Price Per Share: 51.5306
id: F3
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 112468
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Chen Sean Chihhsiang

2026-10-14

Sale

2000

52.4682

110,468

2 days

Filed terms

security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 2000
transaction Price Per Share: 52.4682
id: F4
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 110468
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Chen Sean Chihhsiang

2026-10-14

Sale

4000

53.4363

106,468

2 days

Filed terms

security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 4000
transaction Price Per Share: 53.4363
id: F5
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 106468
direct Or Indirect Ownership: D
nature Of Ownership:

Common Stock

Chen Sean Chihhsiang

2026-10-14

Sale

200

54.27

106,268

2 days

Filed terms

security Title: Common Stock
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: S
equity Swap Involved: 0
id: F1
transaction Shares: 200
transaction Price Per Share: 54.27
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 106268
direct Or Indirect Ownership: D
nature Of Ownership:

Stock Option (Right to Buy) (derivative)

Chen Sean Chihhsiang

2026-10-14

Exercise or conversion

15000

119,423

2 days

Filed terms

security Title: Stock Option (Right to Buy)
conversion Or Exercise Price: 8.12
transaction Date: 2026-10-14
transaction Form Type: 4
transaction Code: M
equity Swap Involved: 0
id: F1
transaction Shares: 15000
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F6
expiration Date: 2029-02-20
underlying Security Title: Common Stock
underlying Security Shares: 15000
shares Owned Following Transaction: 119423
direct Or Indirect Ownership: D
nature Of Ownership:

Filing context

Quantities and prices are shown in the units filed. No trade value is inferred from their product.

Chen Sean Chihhsiang: President and COO.

The filing reports a Rule 10b5-1 trading plan.

F1: The transactions reported in this Form 4 occurred under a Rule 10b5-1 plan adopted by the Reporting Person on June 5, 2026

F2: The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $50.00 to $50.98 per share. The Reporting Person undertakes to provide to the Issuer, any security holder 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.

F3: The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $51.00 to $51.90 per share. The Reporting Person undertakes to provide to the Issuer, any security holder 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.

F4: The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $52.02 to $53.01 per share. The Reporting Person undertakes to provide to the Issuer, any security holder 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.

F5: The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $53.04 to $53.91 per share. The Reporting Person undertakes to provide to the Issuer, any security holder 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.

F6: 1/4 of the shares subject to the option vested on February 21, 2020, and 1/48 of the shares subject to the option vested in equal monthly installments thereafter, subject to the Reporting Person's continued service.