Uber CEO Dara Khosrowshahi at Sun Valley. Drew Angerer / Getty Images

2019 is shaping up to be a potentially big year for massive tech IPOs, with valuations that could reach as high as $100 billion or more. Ride-hailing companies Uber and Lyft have been open about their ambitions to go public, but several other tech companies have begun to hint at upcoming initial public offerings as well. Here are the companies to watch in 2019.

Palantir

The elusive data-mining company backed by Peter Thiel is the latest tech giant to consider an IPO for late 2019, CNBC has learned. Palantir is currently in talks with Morgan Stanley. The Wall Street Journal reported Thursday that the company is also talking to Credit Suisse. Palantir's last funding round in 2015 left it with a reported $20 billion valuation, but the IPO could value the company at up to $41 billion. Palantir expects to take in $750 million in revenue this year. The secretive company is known for providing data tools to companies and governments, and its technology may have been used to help the U.S. government track down Osama Bin Laden, according to Bloomberg.

Uber

Uber's new leadership has been busy reshaping the company's image and getting it ready to go public in 2019. Goldman Sachs and Morgan Stanley reportedly delivered reports to Uber last month, valuing the company at up to $120 billion, The Wall Street Journal reported Tuesday. This far exceeds Uber's latest valuation of $76 billion from its funding round in August. CEO Dara Khosrowshahi has said Uber is aiming to go public in the second half of 2019. Khosrowshahi has spent his time at the helm of Uber trying to regain the trust of its users and investors after co-founder and former CEO Travis Kalanick left the company amid claims of a culture of sexual harassment at Uber.

Lyft

The second-largest ride-hailing app could beat Uber to an IPO. Lyft is planning to go public in early 2019, CNBC reported Tuesday. Sources familiar with the matter said Lyft hired J.P. Morgan Chase to lead the IPO at a public valuation topping $15 billion. This would be on target with the $15.1 billion valuation it received in its latest funding round earlier this year.

Slack

Company messaging app Slack has been eyeing an IPO since 2017, but now it is almost ready to debut on the public market as soon as early 2019, The Wall Street Journal reported last month. Slack could receive more than a $7 billion valuation, the Journal reported, which would be on target for the $7.1 billion valuation it received from its latest funding round this summer.

Airbnb

Airbnb has been more iffy than its peers in committing to an IPO in 2019. "We will be ready to IPO next year, but I don't know if we will," CEO Brian Chesky said at the Recode Code Conference in May. Chesky said he wanted to ensure the move would benefit investors before going forward, adding that Facebook CEO Mark Zuckerberg "is a big proponent" of taking Airbnb public.

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