Also, the California-headquartered company went on an acquisition spree, acquiring as many as 28 start-ups last
year, as it looks to grab consumers' attention, especially those using mobile handheld devices.
CEO Marissa Mayer, who joined the firm in 2012 to revive
its declining fortunes, has been working on "re-imagining"
Yahoo's core businesses across search, communications, media and video.
"Product development expenses for 2011, 2012, and 2013
totaled approximately USD 919 million, USD 886 million and USD
1 billion, respectively, which included stock-based
compensation expense of USD 81 million, USD 74 million and USD 83 million, respectively," the firm said in a US SEC filing.
Yahoo! continually launches, improves and scales products
and features to meet evolving user, advertiser and publisher
needs. Most of the software products and features are
developed internally by the employees, it added.
"Our engineering and production teams are primarily located in our Sunnyvale, California, headquarters, Bangalore, India and Beijing, China," the firm said in a the filing.
Yahoo!, which is increasingly seeing a major chunk of its
usersbase going mobile, aims to make compelling ads and
integrate them with news and information.
Reiterating its strategy of "building products focusing
on mobile first", the firm further said: "Today we have over
400 million monthly mobile users, an increase of more than 150
million users since we launched our new Mobile and Emerging
Products team in October 2012".
Today, mobile traffic represents more than half of its
800 million monthly users (the numbers do not include Internet
Message Access Protocol or Tumblr users), it added.
Yahoo! said increasing mobile traffic has been the result
of an "engaging and inspiring suite of new and revamped
product experiences designed to make users' daily habits