By Rodrigo Campos

(Reuters) - U.S. regulators on Friday suspended trading in Cynk Technology Corp, citing possible market manipulation in the one-time penny stock whose market value rocketed within weeks from less than $20 million to more than $6 billion.

After the virtually unknown company with no assets or revenue skyrocketed in value for no apparent reason, the Securities and Exchange Commission and Financial Industry Regulation Authority (FINRA) decided to pull the plug. Listing its business address in Belize but filing out of Nevada, the company said it intended to create a social network business.

FINRA posted a trading suspension in the stock early on Friday using its "Extraordinary Event Halt" code. The SEC issued its suspension shortly afterward, extending the trading hiatus through July 24.

The SEC cited "concerns regarding the accuracy and adequacy of information in the marketplace and potentially manipulative transactions in Cynk’s common stock."

Shares of Cynk, a development-stage company which SEC filings said formerly went by the name Introbuzz, were hardly ever traded, exchanging hands at pennies per share through late May. Beginning on June 17, shares rocketed from 6 cents to as much as $21.95 at one point on Thursday.

Based on Thursday's closing price of $13.90, its stock market value is $4.05 billion. At its peak, the stock had a higher market value than three dozen members of the S&P 500 including Cablevision Systems, Pitney Bowes, Legg Mason and ADT Corp.

Identified in regulatory filings as a Nevada corporation, it lists a business address in Belize City, Belize. Financial statements with the SEC show no assets, no sales and no positive cash flow. Its last quarterly report, from the third quarter of 2013, shows a net loss of $11,275 for the period.

Its website, site.introbiz.com, lists no phone number. A form for contacting the support group warns that it could take two days to respond.

An investor named Marlon Sanchez was listed as owning 72 percent of the 291 million outstanding shares. But he had sold his stake, according to a June 11 letter to OTC Markets Group Inc, operator of the OTC Pink market on which Cynk shares traded.

The letter, signed by Las Vegas attorney Harold Gewerter, described Javier Romero, a resident of Belize, as the "sole officer and director" of Cynk.

The document, posted on an OTC website, said Romero has owned 210 million shares, roughly 72 percent of outstanding shares, since Feb. 20, 2014, "which he purchased from the former sole officer and director" - Sanchez.

Sanchez, reached by telephone on Friday, said: "I left the company in February and I have no further comment."

Two SEC filings dated in March and April continue to identify Sanchez as the company's president and chief executive officer.

Sanchez also disclosed in an April 2013 filing to the SEC for Introbuzz that he graduated from San Diego State University with a degree in Business Administration Marketing. An alumni official said Sanchez was not in the university's alumni data base.

Calls to the phone number on file at the SEC reached an automated recording saying: "You have reached an unassigned number."

The Belize address on file is The Matalon, Coney Drive, Suite 400 in Belize City. The building's front desk receptionist said the building has no suite 400 and building managers have never been approached to rent space to Cynk.

Regus, the company that rents out space in the business center in Las Vegas where Cynk had its offices, said a company named Introbuzz had offices there through the end of June but no longer operates in the building. They would not elaborate on how long Introbuzz had the offices, or why the company left.

The attorney, Gewerter, responded to Reuters with an email saying he no longer represents the company.

OTC Markets did not immediately return a call for comment.





VOLUME SPIKE

Before June 17, Cynk shares had traded only on three days in 2014, with daily volume not exceeding 2,000 shares. Trades had occurred at either 8 cents a share or 6 cents, its closing price on May 15, when it last recorded trades before mid-June.

Then, activity in the stock exploded.

Volume on June 17 topped 367,000 shares and the price shot to as high as $4.25, before closing the day at $2.25. Trading on every day since then averaged 120,533 shares. The price soared.

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