IAM: Rastetter William H reports a conversion

By AlphaYouPublished Oct 19, 2026Form 4

Stocks in this disclosure

Reported activity

RASTETTER WILLIAM H

Reporting filer

Rastetter William H reports a conversion, not an open-market purchase or sale, in Iambic Therapeutics, Inc.. Form 4 filed Oct 19, 2026 lists 7 entries.

Disclosed: Oct 19, 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	RASTETTER WILLIAM H	2026-10-16	C	Conversion	192579	Not stated (see footnotes)	192,579	3 days	Filed terms security Title: Common Stock transaction Date: 2026-10-16 transaction Form Type: 4 transaction Code: C equity Swap Involved: 0 transaction Shares: 192579 id: F1 id: F2 id: F3 id: F4 transaction Acquired Disposed Code: A shares Owned Following Transaction: 192579 direct Or Indirect Ownership: I nature Of Ownership: See footnote id: F5
Common Stock	RASTETTER WILLIAM H	2026-10-16	C	Conversion	8341	Not stated (see footnotes)	200,920	3 days	Filed terms security Title: Common Stock transaction Date: 2026-10-16 transaction Form Type: 4 transaction Code: C equity Swap Involved: 0 transaction Shares: 8341 id: F6 transaction Acquired Disposed Code: A shares Owned Following Transaction: 200920 direct Or Indirect Ownership: I nature Of Ownership: See footnote id: F5
Series B Convertible Preferred Stock (derivative)	RASTETTER WILLIAM H	2026-10-16	C	Conversion	76801	0	0	3 days	Filed terms security Title: Series B Convertible Preferred Stock id: F1 transaction Date: 2026-10-16 transaction Form Type: 4 transaction Code: C equity Swap Involved: 0 transaction Shares: 76801 transaction Price Per Share: 0 transaction Acquired Disposed Code: D id: F1 id: F1 underlying Security Title: Common Stock underlying Security Shares: 76801 shares Owned Following Transaction: 0 direct Or Indirect Ownership: I nature Of Ownership: See footnote id: F5
Series B-2 Convertible Preferred Stock (derivative)	RASTETTER WILLIAM H	2026-10-16	C	Conversion	64001	0	0	3 days	Filed terms security Title: Series B-2 Convertible Preferred Stock id: F2 transaction Date: 2026-10-16 transaction Form Type: 4 transaction Code: C equity Swap Involved: 0 transaction Shares: 64001 transaction Price Per Share: 0 transaction Acquired Disposed Code: D id: F2 id: F2 underlying Security Title: Common Stock underlying Security Shares: 64001 shares Owned Following Transaction: 0 direct Or Indirect Ownership: I nature Of Ownership: See footnote id: F5
Series B-3 Convertible Preferred Stock (derivative)	RASTETTER WILLIAM H	2026-10-16	C	Conversion	36805	0	0	3 days	Filed terms security Title: Series B-3 Convertible Preferred Stock id: F3 transaction Date: 2026-10-16 transaction Form Type: 4 transaction Code: C equity Swap Involved: 0 transaction Shares: 36805 transaction Price Per Share: 0 transaction Acquired Disposed Code: D id: F3 id: F3 underlying Security Title: Common Stock underlying Security Shares: 36805 shares Owned Following Transaction: 0 direct Or Indirect Ownership: I nature Of Ownership: See footnote id: F5
Series B-4 Convertible Preferred Stock (derivative)	RASTETTER WILLIAM H	2026-10-16	C	Conversion	14972	0	0	3 days	Filed terms security Title: Series B-4 Convertible Preferred Stock id: F4 transaction Date: 2026-10-16 transaction Form Type: 4 transaction Code: C equity Swap Involved: 0 transaction Shares: 14972 transaction Price Per Share: 0 transaction Acquired Disposed Code: D id: F4 id: F4 underlying Security Title: Common Stock underlying Security Shares: 14972 shares Owned Following Transaction: 0 direct Or Indirect Ownership: I nature Of Ownership: See footnote id: F5
Convertible Promissory Notes (derivative)	RASTETTER WILLIAM H	2026-10-16	C	Conversion	8341	0	0	3 days	Filed terms security Title: Convertible Promissory Notes id: F6 transaction Date: 2026-10-16 transaction Form Type: 4 transaction Code: C equity Swap Involved: 0 transaction Shares: 8341 transaction Price Per Share: 0 transaction Acquired Disposed Code: D id: F6 id: F6 underlying Security Title: Common Stock underlying Security Shares: 8341 shares Owned Following Transaction: 0 direct Or Indirect Ownership: I nature Of Ownership: See footnote id: F5

Common Stock

Owner: RASTETTER WILLIAM H
Date: 2026-10-16
Code: C
Action: Conversion
Quantity: 192579
Price: Not stated (see footnotes)
Following holdings: 192,579
Reporting delay: 3 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 192579
id: F1
id: F2
id: F3
id: F4
transaction Acquired Disposed Code: A
shares Owned Following Transaction: 192579
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Common Stock

Owner: RASTETTER WILLIAM H
Date: 2026-10-16
Code: C
Action: Conversion
Quantity: 8341
Price: Not stated (see footnotes)
Following holdings: 200,920
Reporting delay: 3 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 8341
id: F6
transaction Acquired Disposed Code: A
shares Owned Following Transaction: 200920
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Series B Convertible Preferred Stock (derivative)

Owner: RASTETTER WILLIAM H
Date: 2026-10-16
Code: C
Action: Conversion
Quantity: 76801
Price: 0
Following holdings: 0
Reporting delay: 3 days
Filed terms and references: Filed terms
security Title: Series B Convertible Preferred Stock
id: F1
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 76801
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F1
id: F1
underlying Security Title: Common Stock
underlying Security Shares: 76801
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Series B-2 Convertible Preferred Stock (derivative)

Owner: RASTETTER WILLIAM H
Date: 2026-10-16
Code: C
Action: Conversion
Quantity: 64001
Price: 0
Following holdings: 0
Reporting delay: 3 days
Filed terms and references: Filed terms
security Title: Series B-2 Convertible Preferred Stock
id: F2
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 64001
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F2
id: F2
underlying Security Title: Common Stock
underlying Security Shares: 64001
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Series B-3 Convertible Preferred Stock (derivative)

Owner: RASTETTER WILLIAM H
Date: 2026-10-16
Code: C
Action: Conversion
Quantity: 36805
Price: 0
Following holdings: 0
Reporting delay: 3 days
Filed terms and references: Filed terms
security Title: Series B-3 Convertible Preferred Stock
id: F3
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 36805
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F3
id: F3
underlying Security Title: Common Stock
underlying Security Shares: 36805
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Series B-4 Convertible Preferred Stock (derivative)

Owner: RASTETTER WILLIAM H
Date: 2026-10-16
Code: C
Action: Conversion
Quantity: 14972
Price: 0
Following holdings: 0
Reporting delay: 3 days
Filed terms and references: Filed terms
security Title: Series B-4 Convertible Preferred Stock
id: F4
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 14972
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F4
id: F4
underlying Security Title: Common Stock
underlying Security Shares: 14972
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Convertible Promissory Notes (derivative)

Owner: RASTETTER WILLIAM H
Date: 2026-10-16
Code: C
Action: Conversion
Quantity: 8341
Price: 0
Following holdings: 0
Reporting delay: 3 days
Filed terms and references: Filed terms
security Title: Convertible Promissory Notes
id: F6
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 8341
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F6
id: F6
underlying Security Title: Common Stock
underlying Security Shares: 8341
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

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.
RASTETTER WILLIAM H: Director, Other reporting owner.
F1: Each share of Series B Convertible Preferred Stock automatically converted into Common Stock on a one-to-one basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and had no expiration date.
F2: Each share of Series B-2 Convertible Preferred Stock automatically converted into Common Stock on a one-to-one basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and had no expiration date.
F3: Each share of Series B-3 Convertible Preferred Stock automatically converted into Common Stock on a one-to-one basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and had no expiration date.
F4: Each share of Series B-4 Convertible Preferred Stock automatically converted into Common Stock on a one-to-one basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and had no expiration date.
F5: The shares are held of record by the Rastetter Family Trust dated September 2, 2010, for which Dr. Rastetter serves as a trustee.
F6: The conversion price was equal to 85% of the Issuer's initial public offering price of $16.00 per share (reflecting a 15% discount).

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

RASTETTER WILLIAM H

2026-10-16

Conversion

192579

Not stated (see footnotes)

192,579

3 days

Filed terms

security Title: Common Stock
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 192579
id: F1
id: F2
id: F3
id: F4
transaction Acquired Disposed Code: A
shares Owned Following Transaction: 192579
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Common Stock

RASTETTER WILLIAM H

2026-10-16

Conversion

8341

Not stated (see footnotes)

200,920

3 days

Filed terms

security Title: Common Stock
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 8341
id: F6
transaction Acquired Disposed Code: A
shares Owned Following Transaction: 200920
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Series B Convertible Preferred Stock (derivative)

RASTETTER WILLIAM H

2026-10-16

Conversion

76801

3 days

Filed terms

security Title: Series B Convertible Preferred Stock
id: F1
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 76801
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F1
id: F1
underlying Security Title: Common Stock
underlying Security Shares: 76801
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Series B-2 Convertible Preferred Stock (derivative)

RASTETTER WILLIAM H

2026-10-16

Conversion

64001

3 days

Filed terms

security Title: Series B-2 Convertible Preferred Stock
id: F2
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 64001
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F2
id: F2
underlying Security Title: Common Stock
underlying Security Shares: 64001
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Series B-3 Convertible Preferred Stock (derivative)

RASTETTER WILLIAM H

2026-10-16

Conversion

36805

3 days

Filed terms

security Title: Series B-3 Convertible Preferred Stock
id: F3
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 36805
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F3
id: F3
underlying Security Title: Common Stock
underlying Security Shares: 36805
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Series B-4 Convertible Preferred Stock (derivative)

RASTETTER WILLIAM H

2026-10-16

Conversion

14972

3 days

Filed terms

security Title: Series B-4 Convertible Preferred Stock
id: F4
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 14972
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F4
id: F4
underlying Security Title: Common Stock
underlying Security Shares: 14972
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Convertible Promissory Notes (derivative)

RASTETTER WILLIAM H

2026-10-16

Conversion

8341

3 days

Filed terms

security Title: Convertible Promissory Notes
id: F6
transaction Date: 2026-10-16
transaction Form Type: 4
transaction Code: C
equity Swap Involved: 0
transaction Shares: 8341
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F6
id: F6
underlying Security Title: Common Stock
underlying Security Shares: 8341
shares Owned Following Transaction: 0
direct Or Indirect Ownership: I
nature Of Ownership: See footnote
id: F5

Filing context

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

RASTETTER WILLIAM H: Director, Other reporting owner.

F1: Each share of Series B Convertible Preferred Stock automatically converted into Common Stock on a one-to-one basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and had no expiration date.

F2: Each share of Series B-2 Convertible Preferred Stock automatically converted into Common Stock on a one-to-one basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and had no expiration date.

F3: Each share of Series B-3 Convertible Preferred Stock automatically converted into Common Stock on a one-to-one basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and had no expiration date.

F4: Each share of Series B-4 Convertible Preferred Stock automatically converted into Common Stock on a one-to-one basis immediately prior to the completion of the Issuer's initial public offering of Common Stock and had no expiration date.

F5: The shares are held of record by the Rastetter Family Trust dated September 2, 2010, for which Dr. Rastetter serves as a trustee.

F6: The conversion price was equal to 85% of the Issuer's initial public offering price of $16.00 per share (reflecting a 15% discount).