LP == Limited Partner (http://en.wikipedia.org/wiki/Limited_partnership http://en.wikipedia.org/wiki/Limited_partnership) LPs are basically the investors in YC

LP == Limited Partner (http://en.wikipedia.org/wiki/Limited_partnership http://en.wikipedia.org/wiki/Limited_partnership) LPs are basically the investors in YC who remain mostly silent as to the operations of the firm. They participate in the proceeds and receive limited liability from the affairs of the business. Sequoia invested in YC, just as YC invests in startups.