“One surprise on our last fund was that we did a much higher percentage of deals in the U.S. than we had expected,” says Mike Volpi, one of Index’s San Francisco-based partners. “Our target is one-third U.S., but we were up at around 40%. I think it reflects the richness of companies, particularly tech companies, in the U.S. market over the past few years. There also were a larger number of things in New York than we had expected.”

When Index raised its fifth early-stage fund in the summer of 2009, its goal was to invest in tech, life sciences and cleantech companies. The firm soon decided, however, that life sciences and tech investing weren’t compatible out of the same fund — leading it to raise a €150 million life sciences-only vehicle earlier this year. This came shortly after Index also raised a dedicated fund for growth-stage investments, whose portfolio already includes such companies as Etsy, Dropbox and Nasty Gal.

As for cleantech,Volpi says that Index didn’t take long to sour on the sector. “We looked at a lot of deals but didn’t think that many had the same potential as tech deals, because they relied too much on subsidies. We did a couple, including a tire recycling company, but I wouldn’t say that it’s still a focus.”

Volpi adds that Index already has begun investing the new vehicle, and that he hopes many of the companies someday will be able to go public in London. It’s a theme first broached in a blog post last month by Index partner Neil Rimer:

What is more alarming than the track record is the defeatist attitude of European companies considering IPOs. The common sentiment in the boardrooms of these companies is that while in the US the IPO window is open, the London market is shut tight like a porthole. Bulge bracket investment bankers file through in perfunctory beauty parades lamenting that European institutional investors are not interested in buying IPOs and doling out the same patently impractical advice; “Wait or consider going public in America.” Consequently,

It strikes me that this is like saying that there is a bread shortage because there are no buyers of bread. Bakers might stop producing bread if people completely lost the taste for it, but that certainly doesn’t seem to be the case: Shoreditch is as vibrant as ever; there is no shortage of interest in Seedcamp and we have certainly never seen better companies being built in London. So why is it that these companies are not tapping local public markets? Perhaps it is that their management teams and boards are dutifully heeding this advice and perpetuating its circular logic…

In the end, the choice of where to list largely depends on how committed we are to building an integrated ecosystem for entrepreneurship in Europe. If we continue to export our IPOs to the US, we will reinforce the argument that there is no market for IPOs over here and ultimately make it wholly uneconomic for analysts, portfolio managers and investment bankers to devote resources to covering tech stocks traded in London. But if we would like to ensure that European entrepreneurs can build large, sustainable companies that can reliably access the public markets to fund their trajectories, we should think again before accepting the closed IPO window as a fait accompli.

Of course, that blog post came before Facebook’s (FB) IPO debacle. Not a single company has gone public in the U.S. or Europe since that time, with Volpi suggesting that the flaccid post-IPO performances of Groupon (GRPN) and Zynga (ZNGA) also may have contributed to the slowdown.

“Facebook may have made people think a bit more before buying into an IPO, but I don’t believe the window is closed… For Europe to get to where Neil was writing about, however, we need the U.S. market to be reinvigorated so that Europeans see what they’re missing.”

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