Greylock Partners:

Greylock Partners is a private venture capital firm, founded in 1965, with a committed capital of over $2 billion under management.
For over 41 years, they have provided equity capital and support to over 300 growth companies, many of which have gone on to become leaders in their respective sectors. Of these companies, over 125 are now publicly held, while about 100 others have merged successfully with other leading companies.  

Battery Ventures:

Since 1983, Battery Ventures has been investing in technology and innovation, worldwide. The firm partners with entrepreneurs and management teams across technology sectors, geographies, and stages of a company's life, from start-up and expansion financing, to growth equity and buyouts. Battery has raised nearly $3billion since inception.
Battery has supported many breakthrough companies around the world, including: Airespace (acquired by Cisco), Akamai Technologies (AKAM), Cbeyond (CBEY), LIFFE (acquired by Euronext), Neoteris (acquired by NetScreen Technologies), and SigmaTel (SGTL).

ICICI Venture:

ICICI Venture is one of the largest and most successful private equity firms in India with funds under management in excess of USD 2 billion. It is a subsidiary of ICICI Bank, the largest private sector financial services group in India.
Over the years, the firm has built a portfolio of companies across sectors including pharmaceuticals, information technology, media, manufacturing, logistics, textiles, and real estate.