EY is exploring a public listing or partial sale of its global advisory business as part of the most radical transformation of the Big Four accounting firm in two decades, according to people with direct knowledge of the matter.

Selling or listing shares would increase the potential for massive gains for existing EY partners who own and operate the company, reminiscent of Goldman Sachs’ initial public offerings in 1999 and Accenture in 2001.

The 312,000-strong firm, which along with Deloitte, KPMG and PwC dominates the accounting industry, is Consider a historical breakup One of its work is as a solution to conflicts of interest that have plagued the profession and to attract regulatory scrutiny.

EY’s advisory business, which provides tax advice, advisory and deals, generated $26 billion in revenue last year and employs 166,000 advisors.

EY’s auditing business, which generated $14 billion in revenue last year, is likely to remain as a partnership after any breakup. People familiar with the details said some advisors would turn to the audit side to support her work in areas such as taxation.

A newly independent advisory business will have the option of incorporating as a corporation, allowing it to obtain external funding through a sale or public offering. The new investment could help boost growth and compete with larger advisory firms such as Accenture, which reported revenues of $51 billion last year and is valued at nearly $200 billion on the New York Stock Exchange.

The separation would also free up EY’s advisory business to win business from firms that have been audited by EY, opening up a pool of potential new clients who are currently barred under independence rules.

EY has been advised on the planning by JPMorgan and Goldman Sachs, people familiar with the matter said. The banks declined to comment.

The company’s large partners have not yet made a firm proposal to the partners about whether they should proceed with the restructuring and what exactly form it should take.

Selling part of the business to outside shareholders would be a radical departure. A senior partner at another company said selling off parts of the work and handing over windfalls to partners would dramatically change the current structure as it “comes naked and leaves naked” while retaining the company’s capital for the next generation.

The Big Four are organized as networks of legally separate national member firms that pay fees each year for common brands, systems, and technology. This setup prevented them from taking on outside investments and made it difficult for them to push through with radical reforms, which would require broad consensus across the company.

However, many accountants see EY as the best of the big four to drive important international changes because its global chiefs have more influence than competitors, with regular partners wielding more power.

However, EY partners will have the opportunity to vote on any changes. Asked if EY might line up investors ahead of the poll, a person familiar with the matter said: “We are looking at these options. We will be looking to see what is in the right interest of all partners.”

EY and other professional service companies have a “doorbell rings all the time” of Private equity firms seeking investment In parts of their business, this person said. The person added that going public would be more difficult than selling private equity.

The split by EY will force its competitors to decide whether to follow suit.

On Friday, PwC, Deloitte and KPMG said they believe in the benefits of having an audit and consulting business under one roof.

PwC said it had “no plans to change course” while Deloitte said it was “committed to our current business model”. KPMG said the multidisciplinary model “brings a range of benefits”.

The separation is likely to attract opposition from some partners. The Big Four partners said audits have historically had lower profit margins and may struggle to recruit and retain staff, especially expert partners who make most of their money from consulting but provide critical expertise in areas such as taxation.

EY declined to comment on the possibility of a stake sale or initial public offering. Following news of the planned separation on Thursday, global CEO Carmen Di Sibiu told employees in an email on Friday: “No . . . the decisions have been made.”