CNBC's Jim Cramer on Friday expressed some concerns about Palantir Technologies' upcoming public market debut, saying he sees positive trend lines in the company's financials but worried about the power concentrated in its founders' hands. 

"Just don't pay up too much for this one," the "Mad Money" host said. "There's too much mystery to it and too much selfishness, too, at least when it comes to corporate governance." 

Palantir opted to go public through a direct listing, not the traditional IPO process, so it will not be raising new money. Instead, existing shareholders will be allowed to sell their stock holdings to new investors.

Founded in 2003, the company's software platform was initially geared toward the U.S. intelligence community during the wars in Afghanistan and Iraq. It later expanded its product offerings to serve large companies.

Palantir anticipates 42% revenue growth in 2020 to about $1.06 billion, according to a filing earlier this week. That would represent an increase of its 2019 figures, when sales grew 25% to $742.6 million. The newly Denver, Colorado-based company projects better than 30% revenue growth next year. 

"Right now, the company has 125 customers in 36 industries spanning more than 150 countries. They're winning lots of new business, but they're also winning more business from old customers," said Cramer, who noted Palantir also has become more efficient and reduced the time it takes to install their software for a new customer. 

There are some mixed signals on the financial side, Cramer cautioned. The company has a lot of stock-based compensation, used to attract and retain talent, and it also is "a long way from becoming cash flow positive," he said. 

It posted negative $226 million in cash flow from operations in the first half of 2020, according to an SEC filing. "That's not great," Cramer said, but it is an improvement from negative $340 million in the same period a year ago.

"Basically, Palantir still loses lots of money and relies heavily on raising new capital in order to keep running," said Cramer, while noting margins are headed in the right direction. "There's nothing inherently wrong with that — when you've got a huge growth opportunity, you need to spend to take advantage of it — but it's definitely worth keeping in mind." 

Palantir, which is known for its secretive culture, was co-founded by Peter Thiel, the tech entrepreneur and venture capitalist who is a long-time member of Facebook's board of directors. CEO Alex Karp is another founder, along with its president, Stephen Cohen. 

Cramer raised concerns about the corporate governance structure of Palantir, calling it "borderline obnoxious" and the most "egregious" set up he's seen since WeWork's canceled IPO last fall. 

All three of Palantir's founders are awarded what the company calls Class F shares, which have variable voting power. "No matter what, they'll always control 49.9% of the voting power, even if they sell down their positions," Cramer said. 

"This stuff might not seem like it matters, but if Palantir starts screwing up, just remember the common shareholders can't do anything about it," he added. "You're just going to sell if it doesn't work." 

According to The Wall Street Journal, citing sources, Palantir's shares could start trading around $10 each, giving the firm a $22 billion valuation on a fully diluted basis. 

At that price, the stock would trade at 20 times sales, Cramer said. "That makes Palantir cheaper than recent deals, although it's also got much slower growth," he said, likely referencing the recent IPO from cloud company Snowflake.  

He also noted Palantir, thanks to the direct listing process, has locked up all but 20% of its shares until early next year. "Compared to most recent red-hot IPOs, 20% of the float's still pretty high. So just be aware the lockup ends sooner than you might expect," he said.

Cramer said the bottom line ahead of Palantir's direct listing — which is expected Wednesday, although the date has been moved a few times already — is the company's financials are positive, but the corporate governance concerns cannot be ignored.

"I'm hesitant to give this one a full-throated endorsement because I hate the class F shareholders thing —too much like feudalism — but right now the numbers do look good," Cramer said. "If you can get Palantir for around $10, or ideally less on a pullback, you've got my blessing to buy it."