Tracking Insider Buying in Hong Kong: What HKEX Director Disclosures Reveal

When a director of an HKEX-listed company buys or sells shares, they're required to disclose it. These filings are public, but scattered across thousands of individual forms on the HKEX website. Renavon's hkex_disclosures dataset collects all 418,000+ of them into a single queryable table going back to 2003.

The data covers three types of disclosure, each filed on its own form:

• Form 1 — Individual Substantial Shareholder notices (someone acquires or disposes of 5%+ of a listed company)
• Form 2 — Corporate Substantial Shareholder notices (a corporate entity acquires or disposes of 5%+)
• Form 3A — Director/Chief Executive notices (a director or CEO changes their interest in the company's shares)

Each filing includes the person or entity involved, the company, the event type, the date, and — where applicable — the number of shares and price.

Directors buy more than they sell (usually)¶

The most basic question: are insiders net buyers or net sellers? Here are the annual purchase and sale counts for the last six years:

SELECT
    toYear(event_date) AS year,
    countIf(event_code IN ('1101', '1001')) AS purchases,
    countIf(event_code = '1201') AS sales,
    count() AS total_filings
FROM renavon_hkex_disclosures.main.hkex_disclosures
WHERE event_date >= '2020-01-01'
  AND event_date < '2026-01-01'
GROUP BY year
ORDER BY year;

Two patterns stand out:

1. Directors consistently buy more than they sell. In every year from 2020 to 2024, purchases outnumber sales. This makes sense — directors receive shares as compensation and often buy more to signal confidence.

2. 2025 flipped. For the first time, sales exceeded purchases (4,606 vs 4,135). Whether this reflects market conditions, regulatory pressure, or just noise is worth investigating further.

Who buys the most?¶

Some directors are compulsive buyers. Here are the most active share purchasers over the last three years:

SELECT
    person_full_name,
    corporation_name,
    count() AS purchase_events
FROM renavon_hkex_disclosures.main.hkex_disclosures
WHERE event_date >= '2023-01-01'
  AND event_code IN ('1101', '1001')
  AND person_full_name != ''
GROUP BY person_full_name, corporation_name
ORDER BY purchase_events DESC
LIMIT 10;

Ng Chee Siong of Sino Land stands out with 444 purchase filings in three years — that's roughly one every other trading day. These persistent buyers are typically founders or major shareholders steadily increasing their stakes.

Seasonal patterns¶

Do directors buy more at certain times of year? Here's the monthly buy-sell ratio across 2020-2025:

SELECT
    formatDateTime(event_date, '%m') AS month_num,
    CASE formatDateTime(event_date, '%m')
        WHEN '01' THEN 'Jan' WHEN '02' THEN 'Feb' WHEN '03' THEN 'Mar'
        WHEN '04' THEN 'Apr' WHEN '05' THEN 'May' WHEN '06' THEN 'Jun'
        WHEN '07' THEN 'Jul' WHEN '08' THEN 'Aug' WHEN '09' THEN 'Sep'
        WHEN '10' THEN 'Oct' WHEN '11' THEN 'Nov' WHEN '12' THEN 'Dec'
    END AS month,
    countIf(event_code IN ('1101', '1001')) AS purchases,
    countIf(event_code = '1201') AS sales,
    round(countIf(event_code IN ('1101', '1001')) * 1.0 / countIf(event_code = '1201'), 2) AS buy_sell_ratio
FROM renavon_hkex_disclosures.main.hkex_disclosures
WHERE event_date >= '2020-01-01'
  AND event_date < '2026-01-01'
GROUP BY month_num, month
ORDER BY month_num;

April and December have the highest buy-sell ratios (1.83x). February has the lowest (1.19x). The April peak is interesting — it falls right after the annual results reporting season for most HKEX-listed companies, when trading blackout periods lift and directors can resume dealing. September also shows elevated buying, coinciding with the end of interim results blackouts.

February's low ratio likely reflects Chinese New Year — shorter trading month, many directors on holiday, and some companies still in blackout for annual results.

What to do with this data¶

Director disclosure data is most useful as one signal among many. On its own, a single purchase filing tells you little — the director might be averaging down into a falling stock. In aggregate, though, patterns emerge:

• Cluster buying — multiple directors of the same company buying within a short window is a stronger signal than a single purchase
• Size matters — a director spending $10 million is more meaningful than one buying $10,000 (where price data is available in the filing)
• Relative to history — is this director a habitual buyer (like Ng Chee Siong's near-daily purchases at Sino Land), or is this unusual activity?

The queries above run directly on Renavon's hkex_disclosures dataset. The companion hkex_disclosure_codes table maps the event codes to human-readable descriptions, and hkex_directors provides the full director appointment and resignation history.