A series of blunders hit the market debut of BATS Global Markets Exchange Inc Friday, causing its own shares to erroneously trade for less than a penny and confusing investors.

The problems also fouled a trade in shares of Apple Inc , the world's most valuable company, and caused a temporary halt in its shares.

It was an inauspicious debut for BATS, an exchange operator that priced 6.3 million shares at $16 per share late Thursday in an initial public offering. The BATS exchange trades both equities and equity options.

BATS stock dipped to $15.25 at the start of trading on its own exchange. Then a slew of bad trades at less than a penny went through. The trades were later voided.

As BATS began trading, a bad trade for 100 shares of Apple also went through, triggering a circuit breaker that temporarily halted trading of Apple.

At 11:07 a.m. the BATS exchange said it was investigating system issues with trading in symbols in the range A through BF, which include Apple and BATS.

It's just another black eye for the fragmented equity structure, said Joe Saluzzi, co-head of equity trading at Themis Trading in Chatham, New Jersey. Every day we see things like flash crashes and now IPOs that can't get off the ground.

The very low-priced BATS trades took place between 11:14 a.m. and 11:15 a.m. (1514 GMT and 1515 GMT)

The BATS exchange was forced to declare self-help, which means an exchange is dealing with internal problems processing trades and needs to send trades through other venues, such as Nasdaq. The erroneous trades were later canceled by Nasdaq.

BATS said on its website that trading on its exchange would resume at 1:20 p.m. (1720 GMT), but later said there was another delay. It set no time for a resumption, and trading remained halted at $15.25 at 2:20 p.m.

BATS could not be reached for comment.

The glitch on the first day did little to encourage investors. The last thing you want to do as a listing exchange is mess up your introduction to the public investment world - the IPO, said Jason Weisberg, managing director at Seaport Securities Corp.

The awkward debut comes as regulators, led by the Securities and Exchange Commission, have been cracking down on exchanges and looking at the relationship between high frequency trading systems and the exchanges.

The trading snags also came on the same day The Wall Street Journal printed a front-page story saying BATS was the subject of an SEC probe into high frequency trading.

More investigations against exchanges are pending, according to sources.

BATS, headed by 45-year-old Joe Ratterman, was formed in 2005 by major banks and trading firms looking to break the stranglehold that the NYSE and Nasdaq had on U.S. stock trading, forcing the traditional venues to modernize their technology.

Last November, BATS acquired pan-Europe equity exchange Chi-X Europe for $300 million to challenge that region's dominant exchanges with faster and cheaper trading services.

According to BATS' offering documents, the BATS exchange has an 11.3 percent share of the U.S. equity market and a 3.1 percent share of the U.S. equity options market. BATS was scheduled to be the first IPO to list on the exchange.

Its difficult debut Friday led some traders to question whether the exchange is reliable to compete with its bigger rivals.

I think some companies might say 'if they can't handle the IPO of their own stock, how can they handle the IPO of our stock,' said Dennis Dick, a Detroit-based market structure consultant and trading member at Bright Trading LLC. There is going to be a confidence issue of listing on BATS.

(Editing by Alwyn Scott, Dan Grebler and Leslie Adler)