In its latest update to its S-1 filing, Twitter announced that it will be raising the price range for its public offering from $17-20 up to $23-25. That would allow Twitter to raise around $1.75 billion and value the company around $14 billion, up from $10.9 billion. The upgrade indicates that Twitter found strong demand during its investor roadshow, but it has also been conservative all along about its pricing, and many analysts expected this move. The updated documents also revealed patent infringement claims filed against Twitter.