Foursquare backer O’Reilly AlphaTech Ventures raises $85 million.

FORTUNE — O’Reilly AlphaTech Ventures has closed its third fund with $85 million in capital commitments, Fortune has learned. The San Francisco-based firm had begun fundraising earlier this fall with a $75 million target, which was slightly above the $60 million it raised for Fund II in October 2010.

OATV is one of the original “micro-VC” firms, investing in seed-stage rounds that sit somewhere between angel investments and traditional Series A rounds. Typically it prefers to lead $1 million to $2 million seed rounds — which are relatively large — but also will go smaller if the opportunity is right.

Some of the firm’s best-known investments are Bitly, ChartBeat, Codecademy and Foursquare, while exited portfolio companies include TripIt (acquired by Concur for $120m), Instructables (acquired by Autodesk) and Parakey (acquired by Facebook). OATV also is one of the few venture firms that doesn’t scrub its website of failed deals — such as Wesabe or Devver – and to briefly explain why its original investment theses didn’t pan out.

OATV is managed by Bryce Roberts and Marc Jacobsen, with Tim O’Reilly/O’Reilly Media also serving as a general partner.

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