Twitter's IPO could now raise more than $2 billion US, after the company made a regulatory filing that said it now plans to price its shares at between $23 and $25 each.

It previously planned to sell the shares for between $17 and $20 each at the IPO on the New York Stock Exchange, to go ahead Thursday.

Twitter still plans to sell 70 million shares. If all of those shares are sold, the offering's underwriters can buy another 10.5 million shares.

At the $25 share price, Twitter's market value would be around $15.6 billion. Twitter's value is based on 625.2 million outstanding shares expected after the offering, including restricted stock units and stock options.

The San Francisco-based short-messaging service plans to list its stock under the ticker symbol "TWTR" on the NYSE.

As the IPO approaches, there are signs that trouble is brewing for Twitter. Its updated filing indicates IBM is alleging Twitter infringes on "at least three US patents."

IBM has recently issued a letter inviting Twitter to negotiate a business resolution of the patent infringement allegations, the filing said.

Skepticism among investors

And a survey by Associated Press-CNBC poll released Monday indicates skepticism among potential investors.

Some 36 per cent of Americans say buying stock in Twitter would be a good investment, while 47 per cent disagree. Last May, ahead of Facebook's IPO, 51 per cent of Americans said Facebook Inc. would be a good investment. Just 31 per cent didn't agree.

A total of 52 per cent of people ages 18 to 34 say investing in the company's stock is not a good idea.

Twitter has not turned a profit since its launch, but its future depends on advertisements as a primary source of income. The company mainly sells three types of ads: promoted tweets, promoted accounts and promoted trends. A company like Starbucks, for instance, can pay Twitter to promote a single tweet or it can pay the company to ask users to follow its account.

It does not bode well that more than half of Twitter users say they have not noticed advertising. Among the 42 per cent of users who did notice, 31 per cent say they've clicked on or followed one of the promoted items in question.

Unfamiliarity with Twitter

Among the poll's other key findings:

  • One in five Americans say they have a Twitter account. One in 10, meanwhile, looks at Twitter feeds but doesn't have an account of their own.
  • Nearly a quarter of Twitter account holders send tweets at least once a day, while 29 per cent say they never do. More account holders say they read others' tweets daily, 35 per cent.
  • About 30 per cent of Twitter users say they have used the service to register complaints about a product or service or when they are looking for information about services or products.
  • Twitter has billed itself as the place for public, real-time conversations, but only 16 per cent of users say they turn to Twitter frequently for breaking news. That said, 44 per cent of users do so at least some of the time.
  • Just 19 per cent of respondents say they have a "favourable" view of Twitter, while 47 per cent feel the same way about Facebook.
  • A sizable share of Americans aren't familiar with Twitter or don't know what to make of it, with nine per cent saying they have never heard of it and another 12 per cent saying they just don't know how they feel about it.
  • Just 35 per cent of Americans say they think Twitter will be a successful company in five years. More, 49 per cent, think Facebook will be successful in five years.

The Associated Press-CNBC telephone poll was conducted Oct. 25 to 27 by GfK Roper Public Affairs and Corporate Communications among 1,006 U.S. adults. The results have a margin of error of plus or minus 3 percentage points.