Each headquarters and branch of a securities firm may open two omnibus trading accounts in its own name, for purposes of accepting securities trading orders from domestic and foreign (including overseas Chinese and foreign nationals) principals respectively; provided that a mainland area principal may not use an omnibus trading account.
A principal may use an omnibus trading account only after opening a securities trading account; the omnibus trading account may be used to participate in TWSE ordinary trading (i.e., the trading time as specified under Article 3 of the TWSE Operating Rules), after-market fixed-price trading, odd-lot trading, and block trades that are settled on the second business day following the trade date. It may also, after carrying out a securities borrowing transaction through a securities firm under the TWSE Securities Lending and Borrowing Rules, [use the borrowed securities] to trade through the omnibus trading account. A principal that is allowed by regulations to engage in margin trading may engage in margin trading through the omnibus trading account.
If a principal has authorized a trader to conduct trades and handle allocation of trade prices and volumes, it shall provide a power of attorney and specify the allocation of trade price and volume and relevant authorized matters. However, where a same authorized trader is authorized by offshore overseas Chinese or foreign nationals, domestic funds, or units of a same group, the power of attorney may be waived, and the authorized trader shall provide a statement specifying the principals' ID numbers or uniform invoice numbers, names, and other relevant information. The TWSE may, in accordance with operational needs, require securities firms to provide certifying documents relating to the aforesaid authorizations.