Insight Venture Partners Raises One *Billion* Dollars — Updated

Insight Venture Partners has raised a new mountain of money to invest in both software and Internet deals. According to two new SEC filings, the 16-year-old, New York-based firm has closed on at least $1.05 billion from investors, including one lump of $325.8 million and another that totals $725.1 million.

Whether the funds will be managed separately or as one fund remains to be seen. Insight has not yet responded to requests for comment. Presumably, though, much of that money has come from existing investors like Stockholm-based Skandia Insurance Co. At least, when Insight raised its last, $1.25 billion fund, in 2007, it said that a full 80 percent of its capital came from existing investors.

Certainly the firm’s investors have had plenty of reasons to feel optimistic about Insight’s prospects. For starters, Insight has seen three companies go public since 2009, including Solarwinds, whose software is used to manage IT environments, Medidata Solutions, which steamlines clinical development for biotech firms, and the digital advertising company MediaMind Technologies.

More exciting to investors, undoubtedly, is Insight’s stake in Twitter, which the firm nabbed as part of a fall 2009 financing that included Benchmark Capital and Spark Capital among others. Indeed, according to Insight’s filing, the date of the first “sale” of an LP interest in its new fund was on December 20  – less than two months ago.

It’s unclear whether Insight also participated in Twitter’s newest, $200 million round, closed earlier this month. Kleiner Perkins Caufield & Byers led the round; other investors in the financing–which brought Twitter’s total funding to date to $360 million–were not disclosed.

Insight was founded in 1995 by Jeff Horing and Jerry Murdock and has enjoyed a number of wins over the years. Beyond its recent successes, for example, it also scored big when PhotoBucket, a photo-sharing service that raised just $13.5 million over two rounds, sold to Fox Interactive Media for $300 million in 2007.

The firm–which invests in both early-stage deals and late-stage, as a lone investor and in syndicates–has also shown a penchant for outsize bets. Among them is an investment is the textbook rental company Chegg, which has raised $219 million since its founding five years ago. (Kleiner Perkins Caufield & Byers, Foundation Capital and Gabriel Venture Partners are among other of Chegg’s investors.)

Insight has also struck deals overseas. In addition to backing Parallels,  a Swiss virtualization software company that’s also backed by Bessemer Venture Partners and Intel Capital, Horing recently told peHUB that Insight is increasingly interested in Brazil.

It’s more than just talk. Last fall, Insight gave an undisclosed amount of growth-stage financing to Mentez, a Miami-based company that has flourished in Brazil by focusing its games network on Google’s Orkut social network. Horing also recently wrapped up a still-undisclosed e-commerce deal outside São Paulo.

Insight’s newest investment appears to be Kony Solutions, which helps corporate customers design, deploy, and manage their mobile offerings. The company just announced a $19.1 million Series A funding this morning from Insight.

[Ed: My pal Owen Thomas at VentureBeat reminds me that Horing and Murdock invested Photobucket straight from their own pockets, so Insight’s LPs actually didn’t see a return from the deal. Likely the deal strengthened LPs’ belief that the team can identify winners, though. Hopefully.]