"Microsoft and Sony's investments give IV a fresh war chest to buy new patents," said Kevin Jakel, chief executive of Unified Patents, which advises tech companies on alternatives to patent aggregators like IV.
But Apple and Intel's decision is significant because the biggest tech companies have supported IV in the past. "This would be a dramatic departure," Jakel said.
Intellectual Ventures declined to discuss investments. Microsoft, Sony, Intel and Apple also would not comment. It is unclear whether Intel and Apple could still opt to invest in IV's vehicle at a later time.
Created in 2000, Intellectual Ventures has raised about $6 billion and acquired 70,000 patents and other intellectual property assets. The company is seeking to raise $3 billion more, a 2013 investor presentation reviewed by Reuters shows.
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Over the years IV and other firms like it have faced criticism from some in the technology industry, who argue that firms like IV, which do not primarily make products, exploit the patent system by demanding royalties and threatening litigation.
IV argues that by buying patents from inventors, it creates a mechanism for them to capitalize on their ideas. Several large tech companies previously invested in IV, which gave them low-cost licenses to IV's vast patent portfolios as well as a portion of royalties IV collected.
Microsoft, Sony, Apple and Intel all invested in IV's previous funds, court filings show. Prior to co-founding IV, Nathan Myhrvold was chief technology officer at Microsoft working closely with Bill Gates. Another IV co-founder, Peter Detkin, was previously an Intel in-house lawyer.