Since its I.P.O in November, Twitter's shares have more than doubled, but they fell sharply after the company's first earnings report disappointed investors.
Mr. Gordon and other critics of confidential filings say that allowing companies to withhold financial data from the public in the run-up to an offering can distort the public's perception of a company's financial health.
(Read more: Wearable cameracompany GoPro to go public)
It is unclear, however, whether the confidential filing provision has led to a rise in newly public companies that run into trouble.
Supporters of the more confidential process argue that all the information that would be available in a normal I.P.O. is still there for the public to scrutinize, if not all at once. Indeed, the company must still publish revisions to its prospectus. (All correspondence with the S.E.C. is published after the initial stock sale, as it was before the JOBS Act.)
According to a study published by Latham & Watkins, one year after the JOBS Act was enacted, companies on average embarked on their road show 49 days after filing their first public document, more than twice the legal minimum.
"Everything is out in the open," said David Menlow, president of IPOfinancial.com, a research firm. "Eventually, from our perspective, it doesn't really provide an advantage."
The law also allows prospective I.P.O. candidates to meet with big institutions like Fidelity Investments and T. Rowe Price during the quiet period to gauge their interest and collect comments.
"In today's 24/7, Internet-enabled world, it's hard to imagine people poring over securities disclosure documents for more than a month before making a decision whether to invest," said Joel H. Trotter, a partner at Latham & Watkins.
Mr. Trotter advised the Treasury Department on the I.P.O. portion of the JOBS Act. He said that the change was meant to make it easier for private companies to go public, rather than taking the easier route of selling themselves.
The new law extended the confidential filing provision that was already available to foreign companies looking to sell stock in the United States.
"Our bias was, we wanted to remove deterrents to going public so that there's more balance," Mr. Trotter said. "It's an uphill battle for companies seeking to go public."
Still, there is a growing sense among some securities experts that the process is changing the I.P.O. process in unintended ways.
"Companies from GoPro to Twitter are using the JOBS Act confidential filing process in ways that have nothing to do with the rationale lobbyists and politicians espoused when they pushed the act through Congress," Mr. Gordon said, arguing that the law was meant to help truly small companies, not established powerhouses like Twitter or even GoPro.
But there is no sign yet that the pace of confidential filings will slow.
"It is the new normal," said Mr. Ritter of the University of Florida. "Companies like the stealth filing."
—By David Gelles and Michael J. de la Merced, The New York Times.