Longfin’s shares may have surged more than 200 percent Monday, but even its CEO thinks the gains are overdone.

“This market cap is not justified,” the company’s CEO and Chairman Venkat Meenavalli said Monday on CNBC’s “Fast Money.” “I valued my IPO pricing at $5.”

“We are a profitable company. … We have nothing to do with this euphoric mania,” Meenavalli said, later adding again that the $3 billion to $4 billion market value the company has reached “is not a reality.”

Shares of financial technology firm Longfin dropped more than 18 percent in extended-hours trading Monday after closing up nearly 229 percent in a volatile day of trading. At its Monday session high of $142.82 a share, the stock was on pace for a two-day gain of more than 2,500 percent.

The gains followed Friday’s news the company was buying Ziddu.com, which says it’s a microlending company using the same blockchain technology as bitcoin. Ziddu’s unsecured website shows the company has a digital coin trading at 19 cents.

Longfin agreed to buy Ziddu from a private Singapore company called Meridian Enterprises in exchange for 2.5 million shares of the company. Adding confusion and volatility for investors, the filing for the deal showed Meridian is 95-percent-owned by Longfin CEO Meenavalli.

He said on CNBC that Longfin is growing at a 200 percent rate and made $28 million in the past six months. He said Ziddu “doesn’t have any revenue right now” and is still in a testing phase, but he expects the subsidiary to make $3 million next year.

Blockchain technology, of which bitcoin is the first application, eliminates the need for a third-party intermediary by creating rapid, permanent transaction records. Bitcoin itself has surged more than 1,700 percent this year to above $19,000.

Other obscure, small companies have announced name changes or other new ties to blockchain, and have seen their stock surge. The pattern echoes the tech bubble of the late 1990s in which companies would add “dotcom” to the end of their names.

When asked whether he was trying to take advantage of the hype around bitcoin and blockchain, Meenavalli said, “No, not at all.”

New York-based Longfin went public on the Nasdaq on Dec. 13 and has 44 million shares outstanding, according to an email from the company’s investor relations spokesperson Lijie Zhu.

At Monday’s close of $72.38 a share, that gives the company a market value of $3.2 billion. The company was worth $220 million in its debut of around $5 a share.

— CNBC’s Tom Franck contributed to this report.