Stifel downgraded the stock and said it sees "lower visibility" on revenue growth.

"We view shares as fairly-valued at current levels and believe the multiple is likely to remain range bound over the next twelve months as a potential deceleration digestion period lies ahead with lower visibility into near-term revenue growth rates. The upside to Street margin in 1Q would be an encouraging trend all else equal, though the topline deceleration path and questions regarding Alphabet's long-term revenue growth trajectory are likely more meaningful to intermediate-term stock performance in our view, while discretionary spending could also cause opex to tick up again in future quarters. At aftermarket prices, GOOGL shares trade at approximately 22x our 2020E GAAP EPS, matching the three-year historical average of 22x forward two-year EPS."