Longbridge Regulatory Kb

longbridge-regulatory-kb

A structured regulatory knowledge base covering the rules, restrictions, and mechanisms investors face across A-shares, Hong Kong, US equity markets, and cryptocurrency — answers regulatory questions without needing live data lookups.

Response language: match the user's input language — Simplified Chinese / Traditional Chinese / English.

When to use

• "A 股涨跌停规则是什么", "what are A-share price limits", "A 股漲跌停規則"
• "T+1 是什么意思", "what is T+1 settlement"
• "港股可以 T+0 吗", "can I sell HK stocks on the same day I buy"
• "PDT 规则是什么", "explain the PDT rule"
• "美股熔断机制怎么触发", "US circuit breaker trigger levels"
• "A 股退市新规", "new A-share delisting rules"
• "港股碎股和暗盘怎么交易", "odd-lot and grey market in HK"

For live trading session status, supplement with longbridge market-temp. For symbol-specific rules, use longbridge static <SYMBOL> --format json.

A-Share Rules (A股规则)

Price limits (涨跌停)

New listings: first day no limit; days 2–5 follow the limits above.

Settlement (交收)

• T+1: Sell a stock on the day after purchase. Funds from sales available next day.
• T+0: Not permitted for equities (day trading is prohibited for ordinary investors).
• ETFs and convertible bonds: T+0 selling is allowed.

Short selling (融券做空)

• Available only via margin accounts through approved brokers.
• Securities in the approved short-list only (maintained by exchanges).
• No naked short selling — must borrow first.
• Transfer fee: typically 0.05–0.10% daily.

Circuit breakers (熔断)

• Triggered when CSI 300 falls ≥5% (15-min halt) or ≥7% (market close for the day).
• Note: implemented 2016-01-04, suspended 2016-01-08 due to market disruption.

Delisting rules (退市新规, 2024)

• Financial: Net profit < 0 AND revenue < 100M RMB for 2 consecutive years → risk warning; 3 years → delisting.
• Market cap: < 300M RMB for 20 consecutive trading days → delisting warning.
• Turnover: < 2M RMB for 20 consecutive days → delisting warning.
• ST / *ST designation: 1 year of losses → ST; 2 consecutive → *ST; further violations → delisting review.

Stamp duty (印花税)

• 0.1% on sell side only (halved from 0.1% on both sides effective Aug 2023).

HK Stock Rules (港股规则)

Price limits

• No daily price limits on the Hong Kong Stock Exchange.
• Extreme volatility may trigger Volatility Control Mechanism (VCM): 5-minute cooling-off if price moves ±10% in 5 minutes.

Settlement (交收)

• T+2: Standard settlement. Sell on day T; proceeds settled T+2.
• T+0 selling: Allowed — you can sell shares purchased today if settled (e.g. shares transferred to your account already, which typically requires prior holding).

Short selling (卖空)

• Designated short-selling stocks only — SEHK publishes the list.
• No naked short selling — must borrow.
• Short positions must be marked as "short" at order entry.

Odd-lot trading (碎股)

• Board lot = standard trading unit (varies by stock: 100, 200, 500, 1000, 2000 shares, etc.).
• Odd lots (less than one board lot) trade in the odd-lot market at wider spreads.
• Retail investors often receive odd lots from rights issues or stock dividends.

Grey market / dark pool (暗盘)

• Pre-IPO grey market: unofficial OTC trading in IPO shares before listing, typically evening before listing day.
• Provides price discovery but is not regulated by SEHK; settlement risk exists.

Listing criteria / delisting (上市/退市)

• Profit test: Aggregate profit ≥ HK$50M over 3 years (main board). Alternative: market cap test or revenue test.
• Delisting: Prolonged trading suspension (typically > 18 months) triggers delisting review.

Stamp duty (印花税)

• 0.1% on both buyer and seller (total 0.2% per round trip), effective from 2021.

Insider dealing (内幕交易条例)

• Securities and Futures Ordinance (SFO) Cap. 571 governs insider dealing and market manipulation.
• Directors must disclose dealings within 3 business days.

US Stock Rules (美股规则)

Key rules: PDT ($25k minimum, 4 day-trades in 5-day window), Reg T 50% initial margin, T+1 settlement (since May 2024), S&P 500 circuit breakers at -7%/-13%/-20%, Reg SHO short-locate requirement, LULD per-stock bands ±5%.

For full detail see references/us-rules.md. For cryptocurrency regulation and cross-border tax basics see references/crypto-and-tax.md.

CLI (supplementary)

For live trading session status:

longbridge market-temp --format json   # session open/closed, market sentiment

For symbol-specific board lot or margin tier:

longbridge static <SYMBOL> --format json   # verify available fields with --help
longbridge static --help

Output

For each regulatory question:

1. Clear rule statement with the governing authority.
2. Numeric thresholds (%, days, amounts).
3. Consequences of violation / breach.
4. Practical tip for the user.
5. Caveat: rules evolve; link to official source when possible (CSRC / SFC / SEC / FINRA).

Error handling

Related skills

• longbridge-market-temp — live trading session and sentiment
• longbridge-flows — short interest and insider trade data (US)
• longbridge-derivatives — options margin and exercise rules
• longbridge-hedging — hedging strategy design

File layout

skills/longbridge-regulatory-kb/
└── SKILL.md