Can Google's growth placate cash-hungry investors?

What to expect from Google's earnings
Google earnings: Here's what to watch   

Google's second-quarter earnings report Thursday will mark the debut for CFO Ruth Porat. And if the company's growth rate disappoints, expect some questions to flow her way.

The dominant Internet search engine has never paid a dividend or bought back stock, preferring to make big bets on the future of computing while maintaining a massive and expanding pile of cash.

With revenue growth slowing, some shareholders may be getting antsy. That's especially true with the stock down 4.4 percent over the past year, as Facebook, Amazon.com and Apple have each jumped more than 30 percent.

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"Investors will be hyper-focused around any language that suggests there may be a change coming in Google's policy surrounding capital returns to shareholders," wrote Scott Devitt, an analyst at Stifel, in a July 13 report. He has a "hold" rating on the stock.

When to send back cash is a question all companies, even technology leaders, eventually face. Microsoft, Apple, Yahoo and eBay all have programs in place.

Google didn't respond to requests for comment.

Google search questions
Google search questions   

Porat joined the Mountain View, California-based company in May, and before that had a high-profile career on Wall Street, most recently as CFO of Morgan Stanley. She succeeded Patrick Pichette, Google's finance chief of seven years.

At the end of the first quarter, Google had $65.4 billion in cash and short-term investments, a 31 percent increase from two years earlier. Sales growth in the same two-year period was only slightly faster at 33 percent.

"A capital return road map could allow for clearer valuation of Google's $65 bln in cash," wrote Nomura Securities analyst Anthony DiClemente, in a July 13 report titled, "Ms. Porat's Pitch: 2Q15 Preview."

DiClemente has a "buy" rating on the stock and $625 price target, 11 percent higher than Tuesday's closing price of $561.10.

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Analysts on average expect second-quarter revenue of $17.8 billion, representing a growth slowdown to 12 percent from 22 percent in the same period last year, according to Thomson Reuters. Earnings per share likely increased to $5.45 from $4.99, analysts estimate.

Google's control of the Web search market has held steady or increased in recent years, but mobile presents a challenge. Many smartphone users bypass search, going straight to apps, and for those that do use search, the ads they're served haven't been as lucrative for Google as on PCs.

In the first quarter, aggregate cost-per-click fell 7 percent from a year earlier.

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Much of Google's investment has focused on winning the mobile ad wars, whichever direction they take. In addition to pouring money into the Android operating system as well as its own mobile services like YouTube, maps and the Play store, Google recently unveiled an algorithm, dubbed "mobilegeddon" to favor mobile-friendly websites in search results.

No matter how much progress Google makes in e-commerce, payments and other areas where it's attempting to gain mobile traction, search is what matters to the company's income statement.

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"The key question for Google is whether it can monetize mobile as successfully as it has monetized desktop search advertising," wrote Joseph Bonner, an analyst at Argus Research, in a June 9 report. Bonner has a "buy" rating on the stock.

As a newly appointed CFO, Porat hasn't had much time to help improve Google's mobile strategy. But if the company's efforts aren't providing ample returns to investors, they'll be looking to her for other ways to get paid.