SAN FRANCISCO (Reuters) - Yuri Milner, the Russian investor known for his bets on Facebook Inc and Twitter Inc, is pulling out of an arrangement that let him invest automatically in a group of companies participating in a program called Y Combinator.
The companies will instead receive investments from venture-capital firm Khosla Ventures, Y Combinator said in a blog post on Monday.
Milner "has been spending less time focused on seed-stage investing," the blog post said. "Yuri originally came up with the idea for investing in all YC companies, and we're grateful to him for that and for all the years he has participated."
A spokesman for Milner did not immediately respond to a request for comment.
Since announcing his backing of Y Combinator companies in early 2011, the Russian billionaire has stepped up commitments to other areas, especially China. The investment fund he runs, DST Global, has backed Alibaba Group and 360buy.com; his personal investments include online smartphone retailer Xiaomi.
Twice a year, Y Combinator admits about 50 young companies for instruction in entrepreneurship and introductions to key players in Silicon Valley.
Many of its most valuable alumni attended the program well before Milner and other investors began automatically funding all the program's companies.
The graduates that have given Y Combinator its sterling reputation include accommodation service Airbnb, whose founders attended in 2009. File-sharing service Dropbox and Web hosting business Weebly attended in 2007, while digital library Scribd attended in 2006.
"As far as we can tell based on valuations, the companies in recent batches are doing as well as the ones in past batches," Y Combinator co-founder Paul Graham said in an e-mail.
When Milner started automatically backing all Y Combinator companies in 2011, each start-up received $150,000 from Milner and investor Ron Conway, founder of SV Angel, an investment fund. In late 2012, Y Combinator said it would cut the amount to $80,000 and add additional venture firms to the program: Andreessen Horowitz, General Catalyst and Maverick Capital.
Khosla Ventures has previously backed a handful of Y Combinator companies, including grocery-delivery company Instacart and lab-management software company Quartzy.
"KV is exactly the kind of partner we want at YC — we admire their tenacity and willingness to making bold technology bets," the Y Combinator blog post said.
Reporting by Sarah McBride @mcbridesg; Editing by Dan Grebler