Reporting owner · CIK 0002120880
Tan Si-Hui
Visual SEC Form 4 history across 1 companies, 6 transactions and 1 filings.
CSOChief Science OfficerHorizon Quantum Holdings Ltd.
Open-market mix
—buys
Open-market buy performance
90-day forward return on this insider's open-market purchases
Forward return is not available yet
We compute this from each buy's stock performance 90 days after the transaction. The price history is still being populated for this insider's their open-market buys, so the average and median will appear here once the daily price refresh has covered the relevant trading days.
Monthly open-market activity
Reported purchase and sale transaction counts
Buys Sells
No open-market purchases or sales in this history.
Net value flow
Buys minus sells
Mar 26
$0
Jun 26
$0
Aug 26
$0
Sep 26
$0
Transaction texture
Ownership and ticket size
Average P/S size—
Median P/S size—
Direct4
Indirect2
Sep 12, 2026exercise
Filing-only signals
Deterministic matches in this insider's history
No filing-only signal badges matched this history.
Latest Form 4 facts
Quick context from source filings
Latest transaction
No latest transaction fact is available.
Latest buy
No open-market insider purchase is available.
Latest sale
No open-market insider sale is available.
Associated companies
Visual map of known reporting history
Latest insider transactions
Form 4 filings from available history. Click any column to sort; click it again to flip the order.
| ID | Ticker | Insider | Role | Type | Shares | Value | Code | Filed | Trans date |
|---|---|---|---|---|---|---|---|---|---|
| #220349 | HQ | Tan Si-Hui | CSO | exercise | 5.72k | $0 | M | 09/16 | 09/12 |
| #220348 | HQ | Tan Si-Hui | CSO | grant | 91.6k | $0 | A | 09/16 | 06/12 |
| #220347 | HQ | Tan Si-Hui | CSO | grant | 55.0k | — | A | 09/16 | 03/19 |
| #220346 | HQ | Tan Si-Hui | CSO | return | 2.99k | -$4.55M | D | 09/16 | 09/12 |
| #220345 | HQ | Tan Si-Hui | CSO | exercise | 5.72k | $0 | M | 09/16 | 09/12 |
| #220344 | HQ | Tan Si-Hui | CSO | grant | 3.60k | $0 | A | 09/16 | 08/20 |
Tan Si-Hui Insider Activity FAQ
SEC Form 4 context
Who is Tan Si-Hui?
Tan Si-Hui is a reporting owner in SEC Form 4 filings with reporting owner CIK 0002120880.
Which companies has Tan Si-Hui reported transactions for?
Horizon Quantum Holdings Ltd.
When was Tan Si-Hui's latest insider buy?
No open-market insider purchase is available for this period.
When was Tan Si-Hui's latest insider sale?
No open-market insider sale is available for this period.
Where can I see the original SEC filings?
Each transaction row links directly to the source SEC filing so the reported Form 4 details can be reviewed.
Are performance metrics included?
This version does not calculate win rates, forward returns, benchmark-adjusted returns, or high-conviction scores.