Aramco Services Co. building in Houston. Photo: John_Silver/Shutterstock.com

White & Case's role advising Saudi Aramco on its initial public offering hasn't been a secret for years. The scope of the firm's efforts, on the other hand, has remained under wraps until now.

In a Wednesday press release, the firm finally outlined some basic details of its work on the Saudi oil giant's $25.6 billion offering, naming key lawyers involved and providing an estimate of the attorney resources brought to bear: 400 White & Case lawyers across 20 of the firm's global offices.

The firm, which also advised Aramco on its $12 billion bond offering in April, has a long-term relationship with the Aramco that spans nearly seven decades, so it is no surprise that the firm is leading the charge as it goes through its IPO process.

But the breadth of the firm's involvement is still remarkable, with nearly a fifth of the firm's 2,150 attorneys playing some kind of role, based on its announcement.

The deal is, to be fair, the largest IPO in history, besting Alibaba's $25 billion from 2014.

Leading the White & Case team were capital markets partners Sami Al-Louzi (Dubai, United Arab Emirates), Colin Diamond and Gary Kashar (New York), and Inigo Esteve (London); corporate partners Wendell Maddrey, Ivan Paskal and Clark Wohlferd (New York); and litigation partners Carolyn Lamm, Hansel Pham (Washington, D.C.) and Owen Pell (New York).

A team of The Law Office of Megren M. Al-Shaalan also advised Saudi Aramco on the transaction, led by Megren Al-Shaalan and Doug Peel (Riyadh, Saudi Arabia).

"We are extremely honored and privileged to have played a role in the largest IPO in history on behalf of Saudi Aramco, a longstanding client and partner of the firm for nearly 70 years," White & Case's Wohlferd said in a statement. "Few firms can offer this breadth and depth of legal expertise," Kashar added.

Latham & Watkins, which advised the joint financial advisers, coordinators, book-runners and underwriters in relation to the international offering, also announced its deal team Wednesday.

Latham, according to the firm's press release, advised on "non-Saudi law matters" for the underwriters. The team consisted of New York-based capital markets partners Marc Jaffe and Ian Schuman, Washington, D.C., partner Alex Cohen, London partner Craig Nethercott and Dubai partner Nomaan Raja.

After some ups and downs prior to the IPO, including a lowering of the company's target valuation from $2 trillion down to almost $1.4 trillion on the lower end, things looked shaky for the transaction.

Changes in leadership, an attack on a production facility and open hostility with its bankers threatened to derail the deal, not to mention the valuation the Saudis wanted. In the end, the Kingdom opted for a domestic listing, requiring international investors to go through Saudi-based intermediaries.

Still, on Wednesday, the first day of trading on the Saudi Stock Exchange, or Tadawul, the company's shares have risen to their 10% upward limit as investors in Saudi Arabia clamor to buy a piece of the petrol giant.

But that trading is being bolstered by what Prince Abdulaziz, a Saudi oil minister, said is a "friends and family" IPO. Abdulaziz told Bloomberg the IPO is "relying on local retail investors, rich Saudis and regional governments. The Saudi government even spent more than $2 billion of its own cash buying shares."

Aramco's underwriters have an option to offer 15% more shares, or roughly $4.4 billion worth, if the demand warrants it. This would need to be done within the first 30 days of trading and would up the total IPO value to $30 billion, according to The Wall Street Journal.

With the 10% increase in share value, Aramco now has a valuation of $1.877 trillion (with a 'T'), and the Saudi government believes the company can reach the $2 trillion mark.

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