Horizon Quantum Holdings Ltd. (HQ)

Data as of Sep 16, 2026, from SEC Form 4 filings.

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Latest HQ insider trades

Danielle Lambert - Director
Open-market purchase$1.00M
Mar 19, 2026
Qian Yi Amanda Chew - Officer
Grant or award17,857 sh
Aug 17, 2026
Catherine Michele Fitzsimons - Officer

About Horizon Quantum Holdings Ltd. (HQ)

The SEC lists Horizon Quantum Holdings Ltd. under CIK 0002088256, in computer programming services. We track it alongside the rest of the Information Technology sector. Its registration statement was declared effective on 17 February 2026, which clears it to sell shares but does not fix a trading date.

Sector: Information Technology

SEC filings for HQ on EDGAR

HQ Form 4 activity by transaction type, last 90 days

Form 4 transaction type	Transactions	Shares
Grant or award	7	486,631
Option exercise	8	51,268
Derivative transaction	4	8,823

Dollar totals cover purchases and sales only (codes P and S). Grants, option exercises, gifts and tax withholding are counted in shares, because none of them is a trade at a market price.

HQ insider transactions (Form 4)

10 Form 4 filings on record, the earliest from Mar 20, 2026, newest first.

Date	Insider	Transaction	Security	Shares	Price	Value
Aug 17, 2026	Qian Yi Amanda Chew - Officer	Grant or award	Restricted Stock Unit	17,857^{footnote F1}	$0.00^{footnote F1}	-
Footnote F1 (price, shares): Each restricted stock unit ("RSU") represents a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd. (the "Company") upon vesting, for no consideration.
Sep 12, 2026	Catherine Michele Fitzsimons - Officer	Option exercise	Class A Ordinary Shares	2,148^{footnote F1}	$0.00^{footnote F2}	-
Sep 12, 2026	Catherine Michele Fitzsimons - Officer	Derivative	Class A Ordinary Shares	1,122^{footnote F3}	$15.22^{footnote F3}	$17K
Jun 12, 2026	Catherine Michele Fitzsimons - Officer	Grant or award	Restricted Stock Unit	34,372^{footnote F2}	$0.00	-
Sep 12, 2026	Catherine Michele Fitzsimons - Officer	Option exercise	Restricted Stock Unit	2,148^{footnote F1}	$0.00	-
Footnote F1 (shares): On September 12, 2026, 2,148 of Ms. Fitzsimons's RSU's vested. Footnote F2 (price, shares): On June 12, 2026 (the "Grant Date"), Ms. Fitzsimons was granted a total of 34,372 unvested restricted stock units ("RSUs"), each representing a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd… Full note on SEC EDGAR Footnote F3 (price, shares): The reported disposition to the Company reflects the settlement in cash of a portion of the RSUs which vested on September 12, 2026, at a price per ordinary share of $15.22, the last reported sales price of the Company's Class A Ordinary Shares on September 11, 2026.
Sep 12, 2026	Greg Gould - Officer	Option exercise	Class A Ordinary Shares	3,437^{footnote F1}	$0.00^{footnote F2}	-
Sep 12, 2026	Greg Gould - Officer	Derivative	Class A Ordinary Shares	1,272^{footnote F3}	$15.22^{footnote F3}	$19K
Jun 12, 2026	Greg Gould - Officer	Grant or award	Restricted Stock Unit	54,995^{footnote F2}	$0.00	-
Sep 12, 2026	Greg Gould - Officer	Option exercise	Restricted Stock Unit	3,437^{footnote F1}	$0.00	-
Footnote F1 (shares): On September 12, 2026, 3,437 of Mr. Gould's RSU's vested. Footnote F2 (price, shares): On June 12, 2026 (the "Grant Date"), Mr. Gould was granted a total of 54,995 unvested restricted stock unites ("RSUs"), each representing a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd. (the… Full note on SEC EDGAR Footnote F3 (price, shares): The reported disposition to the Company reflects the settlement in cash of a portion of the RSUs which vested on September 12, 2026, at a price per ordinary share of $15.22, the last reported sales price of the Company's Class A Ordinary Shares on September 11, 2026.
Aug 20, 2026	Si-Hui Tan - Officer	Grant or award	Class A Ordinary Shares	3,600^{footnote F1}	$0.00^{footnote F2}	-
Sep 12, 2026	Si-Hui Tan - Officer	Option exercise	Class A Ordinary Shares	5,728^{footnote F4}	$0.00^{footnote F4}	-
Sep 12, 2026	Si-Hui Tan - Officer	Derivative	Class A Ordinary Shares	2,991^{footnote F5}	$15.22^{footnote F5}	$46K
Mar 19, 2026	Si-Hui Tan - Officer	Grant or award	Stock Option (Right to Buy)	55,000^{footnote F7}	-^{footnote F8}	-
Jun 12, 2026	Si-Hui Tan - Officer	Grant or award	Restricted Stock Unit	91,659^{footnote F4}	$0.00	-
Sep 12, 2026	Si-Hui Tan - Officer	Option exercise	Restricted Stock Unit	5,728^{footnote F3}	$0.00	-
Footnote F1 (shares): On August 20, 2026 (the "August Grant Date"), Dr. Tan's spouse was granted a total of unvested 3,600 RSUs. The RSUs granted to Dr. Tan's spouse are subject to his continued employment with the Company and vest in accordance with the following schedule: One quarter (1/4) of the… Full note on SEC EDGAR Footnote F2 (price): Each restricted stock unit ("RSU") represents a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd. (the "Company") upon vesting, for no consideration. Footnote F3 (shares): On September 12, 2026, 5,728 of Dr. Tan's RSU's vested. Footnote F4 (price, shares): On June 12, 2026 (the "June Grant Date"), Dr. Tan was granted a total of 91,659 unvested RSUs. The RSUs granted to Dr. Tan vest in sixteen approximately equal installments on successive quarterly anniversaries of the June Grant Date and are subject to Dr. Tan's continued… Full note on SEC EDGAR Footnote F5 (price, shares): The reported disposition to the Company reflects the settlement in cash of a portion of the RSUs which vested on September 12, 2026, at a price per ordinary share of $15.22, the last reported sales price of the Company's Class A Ordinary Shares on September 11, 2026. Footnote F7 (shares): Of the 55,000 stock options, 37,811 stock options are currently fully vested and exercisable. The remaining stock options vest in five approximately equal quarterly installments beginning on November 20, 2026, subject to Dr. Tan's spouse's continued employment with the Company. Footnote F8 (price): As a result of the closing of the Company's business combination on March 19, 2026, Dr. Tan's spouse's 55,000 Legacy Horizon stock options were exchanged for 55,000 stock options of the Company of an equivalent economic value, with an exercise price per Class A Ordinary Share of… Full note on SEC EDGAR
Sep 12, 2026	Joseph Francis Fitzsimons - Officer	Option exercise	Class A Ordinary Shares	14,321^{footnote F1}	$0.00^{footnote F2}	-
Sep 12, 2026	Joseph Francis Fitzsimons - Officer	Derivative	Class A Ordinary Shares	3,438^{footnote F3}	$15.22^{footnote F3}	$52K
Jun 12, 2026	Joseph Francis Fitzsimons - Officer	Grant or award	Restricted Stock Unit	229,148^{footnote F2}	$0.00	-
Sep 12, 2026	Joseph Francis Fitzsimons - Officer	Option exercise	Restricted Stock Unit	14,321^{footnote F1}	$0.00	-
Footnote F1 (shares): On September 12, 2026, 14,321 of Dr. Fitzsimons's RSU's vested. Footnote F2 (price, shares): On June 12, 2026 (the "Grant Date"), Dr. Fitzsimons was granted a total of 229,148 unvested restricted stock units ("RSUs"), each representing a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd… Full note on SEC EDGAR Footnote F3 (price, shares): The reported disposition to the Company reflects the settlement in cash of a portion of the RSUs which vested on September 12, 2026, at a price per ordinary share of $15.22, the last reported sales price of the Company's Class A Ordinary Shares on September 11, 2026.
Mar 19, 2026	Danielle Lambert - Director	Open-market purchase	Class A Ordinary Shares	84,602	$11.82	$1.00M
Mar 19, 2026	Si-Hui Tan - Officer	Grant or award	Stock Option (Right to Buy)	500,000^{footnote F1}	-^{footnote F4}	-
Footnote F1 (shares): Each stock option is exercisable for 2.43499 Class A Ordinary Shares of Horizon Quantum Holdings Ltd. (the "Company") at a price per share of $0.15. Footnote F4 (price): Pursuant to the BCA and as a result of the closing of the Business Combination, Dr. Tan's 500,000 Legacy Horizon stock options were exchanged for 500,000 stock options of the Company of an equivalent economic value, with an exercise price per Class A Ordinary Share of $0.15.
Mar 19, 2026	Greg Gould - Officer	Grant or award	Stock Option (Right to Buy)	285,300^{footnote F1}	-^{footnote F4}	-
Footnote F1 (shares): Each stock option is exercisable for 2.43499 Class A Ordinary Shares of Horizon Quantum Holdings Ltd. (the "Company") at a price per share of $5.13. Footnote F4 (price): Pursuant to the BCA and as a result of the closing of the Business Combination, Mr. Gould's 285,300 Legacy Horizon stock options were exchanged for 285,300 stock options of the Company of an equivalent economic value, with an exercise price per Class A Ordinary Share of $5.13.
Mar 19, 2026	Joseph Francis Fitzsimons - Officer	Grant or award	Class B Ordinary Shares	19,744,585	-^{footnote F3}	-
Footnote F3 (price): Pursuant to the BCA and as a result of the Business Combination, Dr. Fitzsimons exchanged his then outstanding 8,108,696 ordinary shares of Legacy Horizon for 19,744,585 Class B Ordinary Shares of the Company.
Mar 19, 2026	Harry L. You - Director	Grant or award	Class A Ordinary Shares	1,163,484	-^{footnote F1}	-
Mar 19, 2026	Harry L. You - Director	Grant or award	Warrants	2,884,660	-^{footnote F2}	-
Footnote F1 (price): In connection with the closing of the business combination (the "Business Combination") among Horizon Quantum Holdings Ltd. (the "Issuer"), Horizon Quantum Computing Pte. Ltd. ("Horizon"), and dMY Squared Technology Group, Inc. ("DMY"), these Class A ordinary shares of the… Full note on SEC EDGAR Footnote F2 (price): In connection with the closing of the Business Combination, these warrants of the Issuer were issued pursuant to the terms of the Business Combination Agreement upon the exchange of 2,884,660 warrants of DMY. On the effective date of the Business Combination, the closing price… Full note on SEC EDGAR

HQ insider trading FAQ

What is the latest insider trade for HQ?

Horizon Quantum Holdings Ltd. (HQ) had 5 insider filings in the last 90 days, with the most recent on 2026-09-16. The full record for HQ runs to 10 Form 4 filings, the earliest from 2026-03-20. InsiderAlpha adds new Form 4, Form 144 and 8-K filings as they arrive from SEC EDGAR.

How many insiders are buying HQ stock?

No insider purchases of HQ were filed in the last 90 days. 1 purchase is on record for this company.

How many insiders are selling HQ stock?

No insider sales of HQ were filed in the last 90 days.

Where can I see HQ SEC filings (Form 4, 10-K, 10-Q, 8-K)?

This page collects HQ Form 4 insider transactions, Form 144 sale notices and 8-K filings in one place. Annual 10-K and quarterly 10-Q reports live on the company's SEC EDGAR page.

More Information Technology companies with insider activity

Recent insider filings

The EDGAR links open each original Form 4, so you can check any number on this page against the filing it came from.

Sep 16, 2026 - Qian Yi Amanda Chew view on EDGAR
Sep 16, 2026 - Catherine Michele Fitzsimons view on EDGAR
Sep 16, 2026 - Greg Gould view on EDGAR
Sep 16, 2026 - Si-Hui Tan view on EDGAR
Sep 16, 2026 - Joseph Francis Fitzsimons view on EDGAR
Mar 25, 2026 - Danielle Lambert view on EDGAR
Mar 25, 2026 - Si-Hui Tan view on EDGAR
Mar 25, 2026 - Greg Gould view on EDGAR
Mar 24, 2026 - Joseph Francis Fitzsimons view on EDGAR

Related companies with recent insider activity

Learn more

What the Form 4 transaction codes mean: Grants, option exercises, gifts and tax withholding are not trades on the market. The codes say which is which.
Insider activity in Information Technology: Where HQ's peers are being bought and sold.
Every recent Form 4: The market-wide feed, updated as filings arrive from SEC EDGAR.

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Form 4 transaction type

Transactions

Total value

Grant or award

486,631

Option exercise

51,268

Derivative transaction

8,823

Date

Insider

Transaction

Security

Price

Value

Aug 17, 2026

Qian Yi Amanda Chew - Officer

Grant or award

Restricted Stock Unit

17,857^{footnote F1}

$0.00^{footnote F1}

Footnote F1 (price, shares): Each restricted stock unit ("RSU") represents a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd. (the "Company") upon vesting, for no consideration.

Sep 12, 2026

Catherine Michele Fitzsimons - Officer

Option exercise

Class A Ordinary Shares

2,148^{footnote F1}

$0.00^{footnote F2}

Sep 12, 2026

Catherine Michele Fitzsimons - Officer

Derivative

Class A Ordinary Shares

1,122^{footnote F3}

$15.22^{footnote F3}

$17K

Jun 12, 2026

Catherine Michele Fitzsimons - Officer

Grant or award

Restricted Stock Unit

34,372^{footnote F2}

$0.00

Sep 12, 2026

Catherine Michele Fitzsimons - Officer

Option exercise

Restricted Stock Unit

2,148^{footnote F1}

$0.00

Footnote F1 (shares): On September 12, 2026, 2,148 of Ms. Fitzsimons's RSU's vested.
Footnote F2 (price, shares): On June 12, 2026 (the "Grant Date"), Ms. Fitzsimons was granted a total of 34,372 unvested restricted stock units ("RSUs"), each representing a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd… Full note on SEC EDGAR
Footnote F3 (price, shares): The reported disposition to the Company reflects the settlement in cash of a portion of the RSUs which vested on September 12, 2026, at a price per ordinary share of $15.22, the last reported sales price of the Company's Class A Ordinary Shares on September 11, 2026.

Sep 12, 2026

Greg Gould - Officer

Option exercise

Class A Ordinary Shares

3,437^{footnote F1}

$0.00^{footnote F2}

Sep 12, 2026

Greg Gould - Officer

Derivative

Class A Ordinary Shares

1,272^{footnote F3}

$15.22^{footnote F3}

$19K

Jun 12, 2026

Greg Gould - Officer

Grant or award

Restricted Stock Unit

54,995^{footnote F2}

$0.00

Sep 12, 2026

Greg Gould - Officer

Option exercise

Restricted Stock Unit

3,437^{footnote F1}

$0.00

Footnote F1 (shares): On September 12, 2026, 3,437 of Mr. Gould's RSU's vested.
Footnote F2 (price, shares): On June 12, 2026 (the "Grant Date"), Mr. Gould was granted a total of 54,995 unvested restricted stock unites ("RSUs"), each representing a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd. (the… Full note on SEC EDGAR
Footnote F3 (price, shares): The reported disposition to the Company reflects the settlement in cash of a portion of the RSUs which vested on September 12, 2026, at a price per ordinary share of $15.22, the last reported sales price of the Company's Class A Ordinary Shares on September 11, 2026.

Aug 20, 2026

Si-Hui Tan - Officer

Grant or award

Class A Ordinary Shares

3,600^{footnote F1}

$0.00^{footnote F2}

Sep 12, 2026

Si-Hui Tan - Officer

Option exercise

Class A Ordinary Shares

5,728^{footnote F4}

$0.00^{footnote F4}

Sep 12, 2026

Si-Hui Tan - Officer

Derivative

Class A Ordinary Shares

2,991^{footnote F5}

$15.22^{footnote F5}

$46K

Mar 19, 2026

Si-Hui Tan - Officer

Grant or award

Stock Option (Right to Buy)

55,000^{footnote F7}

-^{footnote F8}

Jun 12, 2026

Si-Hui Tan - Officer

Grant or award

Restricted Stock Unit

91,659^{footnote F4}

$0.00

Sep 12, 2026

Si-Hui Tan - Officer

Option exercise

Restricted Stock Unit

5,728^{footnote F3}

$0.00

Footnote F1 (shares): On August 20, 2026 (the "August Grant Date"), Dr. Tan's spouse was granted a total of unvested 3,600 RSUs. The RSUs granted to Dr. Tan's spouse are subject to his continued employment with the Company and vest in accordance with the following schedule: One quarter (1/4) of the… Full note on SEC EDGAR
Footnote F2 (price): Each restricted stock unit ("RSU") represents a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd. (the "Company") upon vesting, for no consideration.
Footnote F3 (shares): On September 12, 2026, 5,728 of Dr. Tan's RSU's vested.
Footnote F4 (price, shares): On June 12, 2026 (the "June Grant Date"), Dr. Tan was granted a total of 91,659 unvested RSUs. The RSUs granted to Dr. Tan vest in sixteen approximately equal installments on successive quarterly anniversaries of the June Grant Date and are subject to Dr. Tan's continued… Full note on SEC EDGAR
Footnote F5 (price, shares): The reported disposition to the Company reflects the settlement in cash of a portion of the RSUs which vested on September 12, 2026, at a price per ordinary share of $15.22, the last reported sales price of the Company's Class A Ordinary Shares on September 11, 2026.
Footnote F7 (shares): Of the 55,000 stock options, 37,811 stock options are currently fully vested and exercisable. The remaining stock options vest in five approximately equal quarterly installments beginning on November 20, 2026, subject to Dr. Tan's spouse's continued employment with the Company.
Footnote F8 (price): As a result of the closing of the Company's business combination on March 19, 2026, Dr. Tan's spouse's 55,000 Legacy Horizon stock options were exchanged for 55,000 stock options of the Company of an equivalent economic value, with an exercise price per Class A Ordinary Share of… Full note on SEC EDGAR

Sep 12, 2026

Joseph Francis Fitzsimons - Officer

Option exercise

Class A Ordinary Shares

14,321^{footnote F1}

$0.00^{footnote F2}

Sep 12, 2026

Joseph Francis Fitzsimons - Officer

Derivative

Class A Ordinary Shares

3,438^{footnote F3}

$15.22^{footnote F3}

$52K

Jun 12, 2026

Joseph Francis Fitzsimons - Officer

Grant or award

Restricted Stock Unit

229,148^{footnote F2}

$0.00

Sep 12, 2026

Joseph Francis Fitzsimons - Officer

Option exercise

Restricted Stock Unit

14,321^{footnote F1}

$0.00

Footnote F1 (shares): On September 12, 2026, 14,321 of Dr. Fitzsimons's RSU's vested.
Footnote F2 (price, shares): On June 12, 2026 (the "Grant Date"), Dr. Fitzsimons was granted a total of 229,148 unvested restricted stock units ("RSUs"), each representing a contingent right to receive one Class A ordinary share, with no par value ("Class A Ordinary Share"), of Horizon Quantum Holdings Ltd… Full note on SEC EDGAR
Footnote F3 (price, shares): The reported disposition to the Company reflects the settlement in cash of a portion of the RSUs which vested on September 12, 2026, at a price per ordinary share of $15.22, the last reported sales price of the Company's Class A Ordinary Shares on September 11, 2026.

Mar 19, 2026

Danielle Lambert - Director

Open-market purchase

Class A Ordinary Shares

84,602

$11.82

$1.00M

Mar 19, 2026

Si-Hui Tan - Officer

Grant or award

Stock Option (Right to Buy)

500,000^{footnote F1}

-^{footnote F4}

Footnote F1 (shares): Each stock option is exercisable for 2.43499 Class A Ordinary Shares of Horizon Quantum Holdings Ltd. (the "Company") at a price per share of $0.15.
Footnote F4 (price): Pursuant to the BCA and as a result of the closing of the Business Combination, Dr. Tan's 500,000 Legacy Horizon stock options were exchanged for 500,000 stock options of the Company of an equivalent economic value, with an exercise price per Class A Ordinary Share of $0.15.

Mar 19, 2026

Greg Gould - Officer

Grant or award

Stock Option (Right to Buy)

285,300^{footnote F1}

-^{footnote F4}

Footnote F1 (shares): Each stock option is exercisable for 2.43499 Class A Ordinary Shares of Horizon Quantum Holdings Ltd. (the "Company") at a price per share of $5.13.
Footnote F4 (price): Pursuant to the BCA and as a result of the closing of the Business Combination, Mr. Gould's 285,300 Legacy Horizon stock options were exchanged for 285,300 stock options of the Company of an equivalent economic value, with an exercise price per Class A Ordinary Share of $5.13.

Mar 19, 2026

Joseph Francis Fitzsimons - Officer

Grant or award

Class B Ordinary Shares

19,744,585

-^{footnote F3}

Footnote F3 (price): Pursuant to the BCA and as a result of the Business Combination, Dr. Fitzsimons exchanged his then outstanding 8,108,696 ordinary shares of Legacy Horizon for 19,744,585 Class B Ordinary Shares of the Company.

Mar 19, 2026

Harry L. You - Director

Grant or award

Class A Ordinary Shares

1,163,484

-^{footnote F1}

Mar 19, 2026

Harry L. You - Director

Grant or award

Warrants

2,884,660

-^{footnote F2}

Footnote F1 (price): In connection with the closing of the business combination (the "Business Combination") among Horizon Quantum Holdings Ltd. (the "Issuer"), Horizon Quantum Computing Pte. Ltd. ("Horizon"), and dMY Squared Technology Group, Inc. ("DMY"), these Class A ordinary shares of the… Full note on SEC EDGAR
Footnote F2 (price): In connection with the closing of the Business Combination, these warrants of the Issuer were issued pursuant to the terms of the Business Combination Agreement upon the exchange of 2,884,660 warrants of DMY. On the effective date of the Business Combination, the closing price… Full note on SEC EDGAR