Shares of TripAdvisor fell as much as 19 percent on concerns that the travel website's shift away from search engine marketing to new tools like social media is hurting growth.
On Tuesday, the company reported second-quarter sales that missed analysts' estimates and said costs had jumped 33 percent.
Shares of rival Priceline (PCLN.O) were down 5 percent in morning trade on the Nasdaq, while those of Expedia Inc (EXPE.O), from which TripAdvisor (TRIP.O) was spun off in December, fell more than 4 percent.
The shift in TripAdvisor's marketing strategy is aimed at attracting traffic with higher conversion rates and getting advertisers to pay more for placing promotions on the company's website.
However, analysts are concerned the strategy would slow growth in the near term.
"As this program was rolled out over the course of 2Q, revenue growth rates will face a headwind in the near term due to lower traffic volumes, until bid rates from advertisers improve," RBC Capital Markets wrote on a note to clients on Wednesday.
TripAdvisor, which aggregates reviews and opinions about destinations and accommodations throughout the world, depends on advertising and subscription for its revenue.
RBC, which cut its price target on the stock by $7 to $42 and kept its "outperform" rating, said the company's shares could be challenged until meaningful growth returns.
"The stock has been seen as a revenue growth story."
TripAdvisor shares, which have gained 30 percent in the last three months, were down at $36.97 in morning trade on the Nasdaq. They touched a three-month of low of $35.05 earlier in the day. (Reporting by Bijoy Koyitty in Bangalore; Editing by Sreejiraj Eluvangal)