Patent firm Intellectual Ventures secured investment for its latest acquisition fund, without the participation of previous investor Apple, according to Reuters.

Sources said another former investor in the company, Intel, also declined to participate in the latest round, although Microsoft and Sony elected to contribute.

Intellectual Ventures focused on acquiring new investment in 2013 rather than acquiring new patents. It now plans to ramp up patent acquisition with the help of the funds from Microsoft and Sony, according to sources.

Apple and Intel’s decision not to invest in the company again is a departure for major technology companies that have backed Intellectual Ventures in the past. It is unclear whether Apple and Intel could take part in the investment at a later date.

Intellectual Ventures was created in 2000 and has raised around $6 billion to date, enabling it to acquire 70,000 patents and intellectual property assets. An investor presentation in 2013 showed the company is seeking to raise another $3 billion.

There has been much debate about how easy it is for patent owners such as Intellectual Ventures and Rockstar to demand large royalty payments and whether such firms help or hinder innovation.

In December 2012, Intellectual Ventures led a group of 12 companies that acquired 1,100 digital imaging patents from Eastman Kodak for $525 million. The companies were reported to include Apple, Google and Samsung.

Rockstar Consortium, which holds former Nortel patents and is backed by Apple, Microsoft, BlackBerry, Ericsson and Sony, was sued by a group of cable companies in January this year for allegedly refusing to discuss licensing terms and demanding royalties for unspecified patents.

Rockstar previously flexed its muscles in the mobile space, filing lawsuits against Google, Samsung and other Android handset vendors in November last year.