Facebook shares hovered around $32 Wednesday morning, its fourth day of trading, as several banks involved in the company’s initial public offering have come under scrutiny.

Reuters reported Tuesday that the Massachusetts Secretary of the Commonwealth has issued a subpoena to Morgan Stanley, the lead underwriter for the social network’s market debut. The subpoena comes after it was reported that analysts working for Morgan Stanley — as well as analysts at JP Morgan and Goldman Sachs — had all cut their revenue estimates for Facebook after seeing the company’s revised S-1 filing on May 9. In that document, Facebook expressed concern about its ability to respond to consumers’ shift to mobile devices.

Business Insider’s Henry Blodget reports that an unnamed analyst said that a Facebook financial executive told him to cut his estimates, and that Facebook executives were indicating during their roadshow that revenue may not meet high expectations.

Facebook could not immediately be reached for comment on the matter.

Morgan Stanley declined to comment on any regulatory inquiries but said the bank complied with regulations in revising its revenue forecast for Facebook.

“Morgan Stanley followed the same procedures for the Facebook offering that it follows for all IPOs. These procedures are in compliance with all applicable regulations,” the firm said in a statement to The Washington Post. The bank said that a copy of the amended S-1 statement was forwarded to all Morgan Stanley “institutional and retail investors.”

“In response to the information about business trends, a significant number of research analysts in the syndicate who were participating in investor education reduced their earnings views to reflect their estimate of the impact of the new information,” the firm said. “These revised views were taken into account in the pricing of the IPO.”

In another matter that has raised concern about the handling of Facebook’s IPO, a senior Nasdaq Stock Market executive said that the exchange would have stopped the IPO if it had realized how bad its technical problems were going to be on Friday. Facebook’s debut was delayed until 11:30 a.m., after Nasdaq’s systems were overwhelmed with orders in the first few minutes after the stock posted on the exchange.

The Wall Street Journal reported that Eric Noll, the head of Nasdaq OMX’s transaction services, said that the exchange believed that it had a fix for the technical problems and that it would have stopped to fix the issue if it had fully understood what caused the glitch at the time.

Retail investors are suing Nasdaq and Facebook, Reuters reported, claiming that the exchange was negligent when it handled the orders. The report says that suits have been filed in U.S. District Court of Manhattan, as well as in California.

According to a press release from the firm Glancy, Binkow and Goldberg, the suit alleges Facebook and the deal’s underwriters cut their earnings forecasts and passed the information to only a “handful of large investor clients.” The complaint, Lazar v. Facebook, Ine., et al., was filed in the Superior Court for the State of California.

Facebook responded to questions about the lawsuits in a statement Wednesday, saying “We believe the lawsuit is without merit and will defend ourselves vigorously.”

Facebook debuted on the Nasdaq index on Friday. But its initial offering of $38 a share quickly slid to close at $31 a share. The stock declined for the next two trading days, closing at 32 on Tuesday. With share prices at $32, Facebook has a market capitalization of just over $68 billion.

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