Former Google employee Marissa Mayer has been on a hiring spree since becoming CEO of Yahoo, filling out the ranks with qualified people from all over the industry, including a number from her old company.

Yahoo has finally found its chief operating officer (COO), hiring Google executive Henrique de Castro to fill the position, it was announced Tuesday.

According to a filing with the Securities and Exchange Commission, de Castro’s base salary will be $600,000 annually.

He will also be receiving a large compensation package, worth around $57 million. This is made up of $36 million in stock grants, including a one-time retention award of $18 million and $18 million in the form of performance-based stock options, $1 million in “make-whole” cash for giving up compensation from Google and $20 million in stock to replace his shares at Google that will vest over the next four years.

"Henrique is an incredibly accomplished and rigorous business leader, and I'm personally excited to have him join Yahoo!'s strong leadership team," Mayer said in a statement.

"His operational experience in Internet advertising and his proven success in structuring and scaling global organizations make him the perfect fit for Yahoo! as we propel the business to its next phase of growth."

De Castro was previously vice president of Google's worldwide Partner Business Solutions group, where he was responsible for advertising platforms and services for Google's publisher and commerce partners. Before that, he led Google's media, mobile and platforms organization, where he helped to grow the business significantly.

Before joining Google, De Castro worked at Dell Corporation, managing sales and business development operations across Western Europe. He also consulted for McKinsey & Company.

"The combination of Yahoo!'s unique properties with high quality content, its renewed focus on outstanding user experience and its massive reach bring tremendous value to users, advertisers and partners," said de Castro in a statement.

"This is a pivotal point in Yahoo!'s history, and I believe strongly in the opportunity ahead. I can't wait to join Marissa and the team and get started."

De Castro will join Yahoo on or before January 22, 2013, or as soon as he has satisfied his obligations to Google. He will first be based in London, on a temporary basis, until he is able to obtain a work visa to come to the United States. As COO, De Castro will have responsible for Yahoo’s sales, operations, media and business development functions.

Yahoo hires

De Castro is just the latest Google employee to come over to work for Mayer. Her first two hires were also from her old employers.

Mayer brought in former Google product marketing manager Andrew Schulte to be her new chief of staff. Mayer also hired Anne Espiritu, who ran consumer technology PR for Google, to handle corporate communications.

In August, Mayer hired Kathy Savitt as the new CMO at Yahoo.

Savitt was previously the founder and CEO of social commerce website Lockerz, and had been executive VP and CMO of American Eagle and a senior executive at Amazon.

In September, Jacqueline Reses was appointed executive vice president of people and development. Reses previously worked at Goldman Sachs for seven years, before leading the U.S. media group at Apax Partners. Then Ken Goldman was hired to replace outgoing CFO Tim Morse.

It was also rumored in August that Mayer was attempted to woo Katie Jacobs Stanton, Twitter’s VP of international strategy, for an unspecified position at Yahoo.

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