華爾街進入較黑箱作業時代，多數股票交易被隱藏

Recently Yahoo News on-line picked up the following:

Wall Street Enters Darker Age with Most Stock Trading Hidden

Katherine Doherty

Fri, January 24, 2025 at 7:48 a.m. PST·4 min read

(Bloomberg) -- Here’s a surprising new fact about the world’s largest and most-liquid public equity market: Most of the activity on it isn’t public anymore.

For the first time on record, the majority of all trading in US stocks is now consistently occurring outside the country’s exchanges, according to data compiled by Bloomberg.

This off-exchange activity — which happens internally at major firms or in alternative platforms known as dark pools — is on course to account for a record 51.8% of traded volume in January. Barring an unexpected dip, it will be the fifth monthly record in a row, and the third month running that hidden trades make up more than half of all volume.

In other words, the shift “appears to be developing into a longer-term trend and quite possibly a permanent one at that,” Anna Ziotis Kurzrok, head of market structure at Jefferies, wrote in a note to clients this month.

Off-exchange trading has been a growing feature on Wall Street for years, but until now public venues including the New York Stock Exchange and Nasdaq have retained overall dominance of market activity. That’s important because exchanges display the quotes that most participants use to price stocks.

The shift toward off-exchange trading is the culmination of a years-long trend, which if it continues could eventually have implications for how the market functions, according to Larry Tabb, head of market structure at Bloomberg Intelligence.

“Theoretically the more trading that goes off-exchange, the fewer orders there are on-exchange competing to determine the best price,” he said. “This means the pricing on and off-exchange could get worse.”

The Securities and Exchange Commission has in recent years taken steps to try to push more activity back on-exchange by revamping market structure. Of four proposals made by the SEC, only two rules — that tweak the way stocks get priced and trades are executed on and off-exchange — were ultimately passed.

For now the threat to market efficiency remains a distant concern, with 48.2% of trades in January still happening on-exchange. Instead, the change is perhaps more useful as an indicator of the evolving market landscape.

Kurzrok at Jefferies notes that the surge in off-exchange activity corresponds with increased volumes in stocks worth less than $1, which are typically traded by retail investors. That makes sense, since that business is often handled internally by market-making giants like Citadel Securities and Virtu Financial.

When those sub-dollar stocks are stripped out of the data, off-exchange trading remains below 40% of total volume, according to calculations by Jefferies. So the apparent shift away from exchanges “doesn’t necessarily mean trading in one stock or all stocks is going to be worse off on any particular day,” Kurzrok said.

Meanwhile, the number of off-exchange venues that offer an alternative, anonymous way to process trades has been growing.

These alternative-trading systems, or ATS, use different mechanisms to match buyers and sellers without the desired price being displayed on a public exchange, or automated auctions where parties express the value they are willing to buy or sell stocks for. Using those venues helps institutional investors limit information leaking to the market and adversely affecting prices.

“This new style of trading is different,” said Joe Saluzzi of Themis Trading. “The bigger institutions seem to have a better experience where they can command more value.”

About 1.7 billion shares a day changed hands on an ATS in November, the most since March of 2020 and 36% more than a year prior, according to analysis from Bloomberg Intelligence.

At Nasdaq, the second-largest US exchange, Head of Strategic Operations and Public Policy Chuck Mack says the worry is that the move toward off-exchange could ultimately make pricing less efficient and drive up costs for investors and issuers.

“Sometime down the road we may look back and say, ‘how did we get here?’” Mack said. “It’s like boiling a frog. If you boil a frog, the temperature slowly rises, it doesn’t realize and doesn’t jump out so it dies. You don’t realize until its too late.”

Translation

華爾街進入較黑箱作業時代，多數股票交易被隱藏

(彭博社)－關於全球最大、流動性最強的公開股票市場，有一個令人驚訝的新事實：市場上的大部分活動不再是公開的。

彭博社彙編的數據顯示，有史以來第一次，美國股票的絕大部分交易都持續在美國交易所之外進行。

這種場外交易活動（在大型公司內部或被稱為暗池的替代平台進行）預計將佔 1 月交易量的 51.8%，創歷史新高。除非出現意外下滑，否則這將是連續第五個月創下紀錄，也是連續第三個月隱藏交易佔總交易量的一半以上。

Jefferies 市場結構主管 Anna Ziotis Kurzro 在本月給客戶的報告中寫道，換句話說，這種轉變「似乎正在發展成為一種長期趨勢，而且很可能是永久趨勢」。

多年來，場外交易一直是華爾街日益增長的特色，但到目前為止，包括紐約證券交易所和納斯達克在內的公共場所仍然佔據著市場活動的主導地位。這很重要，因為交易所顯示的是大多數參與者用來為股票定價的報價。

彭博產業研究市場結構主管 Larry Tabb 表示，轉向場外交易的改變是多年趨勢的結果，如果這種趨勢持續下去，最終可能對市場運作產生影響。

他說： “理論上，場外交易越多，場內可供決定出競爭最佳價格的訂單就越少”; “這意味著場內和場外的定價可能會變差。”

美國證券交易委員會近年來已採取措施，試圖透過改革市場結構來推動更多的交易活動回歸到交易所。在美國證券交易委員會提出的四項提案中，只有兩項規則, 即調整股票定價, 以及執行場內外交易兩項最終獲得通過。

目前，對市場效率的威脅仍是一個遙遠的問題，1 月 有48.2% 的交易仍在交易所進行。反而，這種變化或許更有用於作為市場格局不斷演變的指標。

Jefferies 的 Kurzrok指出，場外交易活動的激增與價值低於 1 美元的股票交易量的增加是相對應的，這些股票通常由散戶投資者交易。這是有道理的，因為該業務通常由 Citadel Securities 和 Virtu Financial 等做市巨頭內部處理。

根據 Jefferies 的計算，當這些低於一美元的股票從數據中剔除時，場外交易仍佔總交易量的 40% 以下。因此，Kurzrok表示，明顯的場外交易的轉變「並不一定意味著某一天某隻股票或所有股票的交易情況都會變差」。

同時，提供替代性、匿名交易方式的場外交易場所的數量也在增加。

這些替代交易系統（ATS）使用不同的機制來配對買家和賣家，而無需在公共交易所顯示期望價格，或透過自動拍賣讓各方表達願意買賣股票的價值。使用這些場所有助於機構投資者限制資訊洩漏到市場並對價格產生不利影響。

Themis Trading 的 Joe Saluzzi 表示： “這種新的交易方式與眾不同” ; “規模較大的機構似乎有更好的感受，能夠獲取得更佳的股票價值。”

根據 Bloomberg Intelligence 分析，11 月 ATS 每日均成交量約為 17 億股，為 2020 年 3 月以來的最高水平，比一年前增長了 36%。

美國第二大交易所納斯達克的策略營運和公共政策主管 Chuck Mack表示，人們擔心轉向場外交易最終可能會降低定價機制的效能，並推高投資者和發行人的成本。

Mack 說: 「將來有一天我們可能會回顧過去並問自己，『我們是怎麼走到這一步的？』」; 「這就像煮青蛙一樣。如果你煮一隻青蛙，溫度慢慢上升，青蛙卻沒有意識到，也沒有跳出來，所以它就死了。直到為時已晚，你才會意識到」。

So, it is surprising to note that the world’s largest and most-liquid public equity market has most of its activity done not in public. The majority of all trading in US stocks is now consistently occurring outside the country’s exchanges, according Bloomberg. This new style of trading favors the bigger institutions that seem to have a better experience where they can command more value when they do transactions. The worry is that the move toward off-exchange could ultimately make pricing less efficient and drive-up costs for investors and issuers.