The San Francisco company -- whose "tweet" text messages limited to 140 characters have become a social phenomenon, with more than 500 million messages sent daily worldwide -- hopes to complete its initial public offering by Thanksgiving but may postpone it until next year if the markets are unreceptive, people briefed on the matter told The New York Times.
The likelihood of unreceptivity will likely increase if the U.S. government shutdown goes on for weeks, the Times said.
Twitter plans to kick off a "road show" to potential investors in about three weeks.
The company, founded in March 2006 as a side project of a floundering start-up podcasting company called Odeo, is now worth about $9.7 billion, an internal valuation of its shares from Aug. 5 indicates.
The social networking and microblogging service said in a regulatory filing its biggest individual shareholders are co-founders Evan Williams, 41, who owns about 12 percent of the company, and Jack Dorsey, 36, who owns 4.9 percent.
The company -- which reported 218.3 million average monthly active users in the second quarter, up 44 percent from the same 2012 period -- said its revenue more than doubled to $254 million in the first six months of this year.
But it also said its net loss grew 40 percent to $69 million in this year's first six months as the company's expenses ballooned to push and support quick growth.
It reported a net loss of $79 million for all of last year.
Prices for Twitter advertisements, which make up most of the company's revenue, are falling, the prospectus indicated.
Like Facebook Inc., Twitter makes money mostly by selling ads based on users' posts.
About 75 percent of Twitter's revenue is from the United States, even though that same percentage of monthly users is outside the United States.
The company expects its business to grow overseas, especially in places such as Argentina, France, Japan, Russia, Saudi Arabia and South Africa, the documents indicate.
The same three banks led Facebook's IPO.
Bank of America Merrill Lynch, the corporate and investment banking division of Bank of America Corp., and Deutsche Bank AG are also underwriters.
Twitter didn't say if it will trade its stock on the New York Stock Exchange or the Nasdaq Stock Market.
The company said in a note "hostile or inappropriate usage" of its platform could hurt its business prospects.
Some high-profile Twitter accounts have been hacked in recent months. In one example, Burger King Corp.'s account was hacked Feb. 18 to look like it was McDonald's Corp. The hackers said incorrectly Burger King "just got sold to McDonald's" because its signature Whopper sandwich "flopped."