Amazon is undoubtedly the real winner of its high-profile HQ2 search. Not only did it receive generous incentive packages from New York and Virginia in a public bidding war, but it also pocketed some free publicity.

The buzz related to the HQ2 search was worth at least $42 million, according to Apex Marketing, which tracks the value of media placement and sponsorships. Apex looked into media coverage, including print, TV and online, since the beginning of this year and social media discussions since November. In the past two weeks alone, HQ2-related social media discussions have generated over $8.6 million worth of attention.

Eric Smallwood, president of Apex Marketing Group, said the HQ2 search has been particularly good at grabbing people’s attention. “It’s in the national news because it’s about Amazon. It also has local influence since there were 20 cities on the shortlist,” Smallwood said. Given the unusual scale and relevance, both national and local media have been consistently covering the matter.

And when Amazon made big announcements like the shortlist of cities in January and its final decision this week, it dominated the headlines. Amazon HQ2 became a top trending topic on social media like Twitter and LinkedIn.

While calling it a “smart marketing campaign,” Smallwood said the marketing value is just an extra bonus Amazon got from the headquarters search. “At the end of the day, it’s calling for the best deal states could offer.” The value is just a drop in the bucket compared to what the e-commerce giant actually spent on advertising and promotions. Last year, Amazon spent an estimated $3.4 billion on ads and marketing campaigns in the U.S., according to Ad Age.

HQ2 costly for cities

The 20 cities on the shortlist and final two winners, New York City and Arlington, Virginia, also got a lot of media attention. But unlike for Amazon, the publicity wasn’t free for municipalities. Philadelphia, for example, reportedly sunk more than $500,000 into trying to get Amazon to locate there, mostly for research and marketing materials for its proposal.

Meanwhile, other tech giants have taken a different approach. Google is reportedly quietly expanding its footprints in New York City, adding space that could house 20,000 staff. Apple, another company in the $1 trillion club, pledged to invest $30 billion to build its second campus. But Tim Cook, Apple’s CEO, said no to a public bidding process and the free publicity coming with it.

“We wanted to narrow it so we prevented this auction kind of process that we want to stay out of,” Cook said in January. Apple plans to announce the location of the site later this year.

Krystal Hu covers technology and economy for Yahoo Finance. Follow her on Twitter.

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