Investors are worried about Expedia.com’s future, following news that the website has been demoted by Google in search engine results. The travel price comparison company’s visibility in search results has reported dropped 25 percent, which on the Internet is the equivalent of moving your company’s billboards from downtown Manhattan to Antarctica.

Neither company has said why yet, but there’s speculation that Expedia may have engaged in the dubious practice of trying to buy links. That’s what happened to rap lyrics website Rap Genius recently.

It could just be a tweak in Google’s algorithm, which is constantly being updated by engineers. But there have also been rumors that the tech giant is experimenting with its own travel price comparison product.

And there are growing questions — as the company faces an antitrust case in Europe — about whether the company might have too much influence about how we access information on the web.