Jobber: legacy LSE market maker role explained
By Ken Chigbo, Founder, KenMacro. Published 2026-05-13.
Quick answer
A jobber was a principal dealer on the London Stock Exchange floor who quoted two-way prices in shares to stockbrokers, earning a turn on the spread between bid and offer. Jobbers could not deal directly with the public. The role was abolished by the 1986 Big Bang reforms, which merged jobbing and broking functions.
What is jobber?
A jobber was a member firm of the London Stock Exchange that acted as a principal market maker on the trading floor, holding inventory in specific shares and quoting continuous bid and offer prices to stockbrokers. Jobbers operated under a strict single capacity system, meaning they were forbidden from dealing directly with public clients. Their profit came from the jobber’s turn, the difference between the price at which they bought stock and the price at which they sold it. The role defined British equity market structure for over a century until deregulation in October 1986.
How traders use jobber
Modern traders do not interact with jobbers, since the role no longer exists, but the desk treats the concept as essential context for understanding how dealer-driven liquidity works today. Contemporary equivalents include designated market makers on the NYSE, retail market makers handling internalised flow, and dealing desk brokers in retail forex who warehouse client positions rather than passing them to liquidity providers. The mechanical principle is identical: a principal quotes two-way prices, captures the spread as compensation for inventory risk, and manages exposure by skewing quotes or hedging externally. Understanding the jobber model helps retail traders recognise why dealing desk brokers can offer fixed spreads and instant execution, and why the conflict of interest critique applied to jobbers in the 1980s still shapes regulatory thinking around principal trading and best execution today.
Worked example of how a jobber operated
Suppose a London stockbroker in 1985 received a client order to buy 5,000 shares of a major industrial company. The broker walked to the relevant jobber’s pitch on the LSE floor without revealing whether they were a buyer or seller. The jobber quoted a two-way price, for example 240 to 244 pence. The broker hit the offer at 244, taking the shares from the jobber’s book. The jobber, now short 5,000 shares, would raise their quote slightly to attract a seller, capturing the four-pence turn once the position was flattened.
Open a Vantage raw-spread account
Frequently asked
What is the difference between a jobber and a stockbroker?
A jobber was a principal dealer who quoted two-way prices and held stock on their own book, profiting from the spread. A stockbroker was an agent acting for public clients, charging commission for executing orders with jobbers. Under the pre-1986 single capacity system, the two functions were strictly separated. Brokers could not make markets and jobbers could not deal with the public. Big Bang abolished this separation, creating the dual capacity broker dealer firms that dominate London today.
When did jobbers stop existing?
Jobbers ceased to exist as a distinct category on 27 October 1986, the date of the London Stock Exchange’s Big Bang reforms. The deregulation package abolished fixed commissions, ended the single capacity rule separating jobbers from brokers, opened LSE membership to foreign and corporate owners, and moved trading from the physical floor to screen-based quotation through SEAQ. Former jobbing firms were absorbed into integrated broker dealers, many of which were acquired by American and European investment banks during the same period.
Is a jobber the same as a market maker?
Functionally yes, structurally no. Both quote two-way prices as principal and earn the spread. However, jobber refers specifically to the pre-1986 LSE floor role operating under single capacity rules, while market maker is the modern term used across electronic equity, bond, and derivatives markets. Today’s market makers can deal with any counterparty, operate from screens rather than a physical pitch, and often sit within universal banks that also run agency broking, something a jobber was legally forbidden to do.
Why was the jobber system abolished?
The single capacity system was seen as restrictive, uncompetitive, and unable to handle the scale of international capital flows emerging in the 1980s. Fixed commissions kept costs high for institutional investors, and the separation of jobbers and brokers prevented British firms from competing with integrated American investment banks. The Thatcher government negotiated the reform package with the LSE to settle a Restrictive Practices Court case. The result was a more competitive, electronic, and globally integrated London market, at the cost of the traditional partnership culture.
Related from the desk
Educational analysis only. Past performance does not guarantee future results. Manage risk against your own portfolio.
From the desk, free
Get the macro framework the desk actually trades
The same regime-first framework behind every call on this site, plus the weekly macro brief. Free. No spam, unsubscribe anytime.
Continue reading
From the desk
Where this gets traded
Reading the macro driver is half of it. The other half is an account that holds execution when the driver actually moves the tape. See the KenMacro desk guide to the best brokers for macro traders.
Read the desk guide →