Alphabet's (GOOGL - Get Report)  first-quarter revenue growth was its slowest in three years, causing analysts to grow somewhat tepid on the search giant. 

The stock was falling 8.2% to $1,190.60 a share on Tuesday morning.

Although Alphabet beat estimates on earnings per share ($11.90 v. estimates of $10.61), it missed revenue expectations, posting $36.34 billion versus consensus estimates of $37.33 billion. That's a year-over-year growth rate of 17%, marking the first time in three years that Google's quarterly revenue growth was less than 20%.

Much of the disappointing revenue result was driven by an advertising product change Google made, most significantly on the core Google platform and also likely YouTube. 

Analysts see the change as largely temporary, but a lack of visibility into Google's ad products prompted several to lower estimates. Here's what they were saying: 

Jefferies, Buy, PT Maintained at $1,450

Analyst Brent Thill didn't lower his price target, but reduced EPS estimates, writing "the continued lack of transparency was troubling to investors, which drove stock down 7%." He added, "GOOGL will need to rebound in Q2 to demonstrate Q1 was not a trend. One quarter does not make a trend, but we acknowledge that Q1 results warrant caution."

Thill lowered his EPS estimates for 2019 and 2020 to $48.43 and $53.69 respectively, from $48.94 and $56.62 . 

Stifel, Downgraded to Hold, PT Maintained at $1,287

"The unexpected degree of revenue deceleration and lower visibility into the near-term reacceleration/deceleration potential lead us to believe the multiple on shares may be challenged to move meaningfully higher over the next twelve months," wrote analyst Scott Devitt. "We move to a Hold rating as a result." The stock currently trades at a 12 month forward earnings multiple of 23, which many analysts now find to be close to fair value.

BMO Capital Markets, Market Perform, PT Dropped From $1,200 to $1,150 

"Timing of product changes in ads (a year ago) impacted growth, as foreshadowed last Q. But little color was added, adding risk to consensus EPS," said analyst Daniel Salmon. "We prefer AMZN (AMZN - Get Report) for share gains in online advertising." Salmon lowered his 2019 and 2020 EPS expectations to $43.22 and $48.90, respectively, from $43.41 and $51.17. 

Morgan Stanley, Overweight, PT Dropped From $1,500 to $1,425 

"1Q Websites deceleration and uncertain forward trajectory highlight the need for better transparency and will likely remain key to long-term valuation," analyst Brian Nowak wrote. "That said, we remain positive on GOOGL's leading 'staple-like' ecosystem and valuation support." Many on Wall Street have likened Google's core search business to that of a staple good or service, providing some level of support for the tech giant's valuation. 

JPM, Overweight, PT Raised From $1,250 to $1,310 

Analyst Douglas Anmuth's raised price target is largely a result of non-core business segments, but he also lowered his 2019 and 2020 EPS estimates. "Our 2019/2020 revenue & GAAP EPS all come down about 2% as improved Other Bets losses partly offset slower Google Segment revenue growth," Anmuth said. He lowered expected EPS to $45.44 in 2019 from $46.47, and to $53.15 in 2020 from $54.23. 

RBC Capital Markets, Outperform, PT Maintained at $1,300

"We're modest buyers on the 7% AM pullback; we'd be material buyers on a material pullback," said analyst Mark Mahaney. "We don't believe GOOGL is going through a material, sustained growth deceleration. 1) The TAM [total addressable market] remains $1T+ in global advertising/marketing spend. 2) Based on our extensive survey work, we don't see evidence of changes in Marketers' view of Google - budget allocations, future spend intentions, or perceived ROI [return on investment]."

Barclays, Overweight, PT Dropped From $1,350 to $1,315

"Google bricks the first quarter lay-up," analyst Ross Sandler said, referring to the fact that google usually meets revenue estimates for the quarter. "The revenue miss is likely to leave a cloud over the story for a while, as GOOG had not printed a deceleration of this magnitude in 4 years."

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