San Francisco-based venture firm Catamount Ventures announced that it closed its fourth fund at $80 million, according to VentureWire. It plans to use the smaller fund to back early-stage companies in the IT and cleantech sectors.

The fund had initially raised $74.15 million in February, but was able to tack on an additional $15 million from an undisclosed source. In fact, Catamount has declined to name any of its contributors, though a regulatory filing for the fundraise lists BP, Horsley Bridge Partners and Legacy Ventures. It says it is starting to lean more heavily on institutional investors as opposed to individual limited partners -- who provided the bulk of the firm's first three funds.

Catamount raised its first fund in 2002, amounting to $15 million. This was followed by a $30 million fund in 2005 and an $85 million fund in the first half of 2007. The fourth fund, the one just announced, has yet to be used for any investments -- though deals may be less than a week away according to management.

The firm's current portfolio includes sustainable technology companies Grid Net, Ecohaus and Verdiem, consumer internet companies CafePress, Flock and Linden Lab (maker of Second Life), and enterprise technology companies eSilicon, Real Time Genomics and Siterra.