Scribd began in 2007 as a document sharing service but has since evolved into a huge digital library for subscribing to books, offering unlimited access to about 500,000 e-books for $8.99 monthly. The Y-Combinator graduate company has raised $22 million in additional funding in a round led by Khosla Ventures and including Redpoint Ventures, Charles River Ventures and Silicon Valley Bank.

The conditions instate Khosla partner Keith Rabois on Scribd’s board as an observer. Rabois is optimistic about the company’s growth and believes, “With over 80 million users in nearly every country, the Scribd team is well positioned to grow a massive global audience.”

The CEO Trip Adler commented that the e-book service now attracts more than 80 million unique visitors every month. He also talked about the company’s growing fortune as the average subscriptions increase at the rate of 31 percent each month. The company introduced the latest audio book feature just a couple of months back which has proved to be an enormous success, surpassing the company’s expectations.

The e-book service now works with two of the big five publishers — HarperCollins and Simon & Schuster. The company’s total funding is $48 million.

On future plans for the company with the new funding, Adler said he plans to spend the money on improving the reading experience and the algorithmic book recommendations, among other things as well as continue to expand the content base of Scribd.

“By the end of [2015], we’ll be able to basically say almost all of the significant (publishers) in the industry are on-board,” he said.