The bi-coastal firm has traditionally raised “generalist” funds, which have invested over $9 billion in more than 500 companies since 1978. But Oak had some fundraising troubles last time around, raising south of $800 million for a 13th fund that originally was targeting $1.5 billion (which already was a significant decrease from the $2.5 billion it had raised for Fund XI in 2006). Now the firm is abandoning its traditional strategy, instead choosing to raise a pair of Oak-branded funds that will focus on particular sectors.

One of the funds already is in market, and will focus on healthcare and financial technology companies. It is targeting around $400 million, and will be led by Oak partners like Anne Lamot and Andrew Adams. My guess is that its marketing pitch will center around a number of its wins in the healthcare SaaS market, like AthenaHealth (ATHN), BenefitFocus (BNFT) and Castlight (CSLT).

The other will focus on information technology companies, and is expected to begin fundraising later this year or in early 2015.

A source familiar with the situation says that a big driver for the change was that Oak’s healthcare and financial technology deals tended to be later-stage, whereas its IT deals tended to be earlier-stage.

According to the Oregon Public Employees Retirement Fund, Oak’s 12th fund had a 3.6% internal rate of return (IRR) and 1.16x total value multiple through Q3 2013. Its 13th fund had a 12.5% IRR and 1.2x total value multiple, and was more than 55% called down.

Expect the entire firm to continue investing Fund XIII, and to manage the legacy portfolio.

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