Microsoft was unable to deter one of its key engineers, Blaise Agüera y Arcas, from leaving the company and joining Google. Courtesy / Microsoft

Scroogled [skr-oo-gulld],” as defined by Microsoft, is “Google’s ongoing use of invasive tactics and Web-centric devices to maximize their profits.” Microsoft isn’t ashamed of its distaste toward Google; in fact, the Redmond, Wash.-based Windows maker has a full website dedicated to all of the ways consumers are supposedly “scroogled” by Google for the sake of ad revenue, pointing at several Google products like the Chromebook, Gmail and the Google Play Store.

Microsoft has released several anti-Google “Scroogled” ads, but the campaign was not enough to deter one of Microsoft’s key engineers, Blaise Agüera y Arcas, from leaving the company and joining Google.

Agüera y Arcas joined Microsoft after the company acquired his Princeton, N.J.-based startup company, Seadragon Software, for an undisclosed sum in 2006 (prior to the deal, Seadragon Software raised $4 million in venture capital and angel funding). Seadragon Software powered many important pieces of Microsoft software, including Silverlight, Pivot and Photosynth, and Agüera y Arcas was one of the key architects behind Bing Maps, Microsoft’s mapping and navigation service.

In a blog post, Agüera y Arcas called the decision to move from Microsoft to Google as “the hardest decision of my life.”

“On one hand, of course this is tremen­dously excit­ing; Google is a com­pany of grand ambi­tions and bril­liant peo­ple,” Agüera y Arcas said in the blog post. “On the other hand, it has been hard — very hard — to detach emo­tion­ally from Microsoft. The company’s lead­er­ship has been con­sis­tently good to me over these past eight years, and it has been a time filled with cre­ativ­ity and growth and good friends. It’s painful to leave behind so many won­der­ful ongo­ing projects, and even moreso to leave behind such a great team.”

The timing for Agüera y Arcas’ departure is interesting, considering Microsoft recently released a new preview of Photosynth, another product built by Agüera y Arcas, on Dec. 10. Agüera y Arcas actually demonstrated Microsoft Photosynth at a TED Talk in 2007, where the Microsoft engineer had an opportunity to showcase how people could link all the world’s photos into the company’s software.

Agüera y Arcas is the third notable senior Microsoft employee to join Google, which is a surprising move for the engineer considering the other two transfers didn’t work out so well.

In November 2004, Microsoft’s then-CEO Steve Ballmer reportedly threw a chair across the room when he was told Mark Lucovsky, another distinguished Microsoft engineer, would be leaving for Google; he also called Google chairman Eric Schmidt a “f--king p--sy,” and added, “I’m going to f--king bury that guy. I have done it before and I will do it again. I’m going to f--ing kill Google.” That following July, Microsoft sued Google and former Microsoft vp Kai-Fu Lee, whom Google had hired for more than $10 million, for violating Lee’s noncompete agreement he had signed with Microsoft.

“He was a great colleague and we wish him the best in his future endeavors,” Adam Sohn, a spokesperson for Microsoft, told the New York Times.

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