Silicon Valley venture capital firm Khosla Ventures is looking to keep backing early-stage startups. The firm is raising a $400 million seed fund, according to a filing today with the U.S. Securities and Exchange Commission.

In June, the firm started to raise a $1 billion fund.

Vinod Khosla, Keith Rabois, Samir Kaul, and David Weiden are listed in the new filing.

Other firms that invest in seed rounds have also been raising money lately. Formation 8, which invests in seed-stage funding rounds, closed its second fund earlier this month. SV Angel was raising a new $70 million fund in July. True Ventures came through with a $250 million fund in February.

Sun Microsystems cofounder Vinod Khosla opened Khosla Ventures in 2004, after a stint as an investor at Kleiner Perkins Caufield & Byers. The firm has its headquarters in Menlo Park, Calif.

Recent Khosla Ventures investments include deep-learning startup MetaMind, real estate startup Opendoor, and shopping-app maker Strut.