Leading open source advocates will this summer meet some of the biggest software companies that have built up businesses on the back of open source software, to negotiate terms for the companies to give something back to the community. Bruce Perens, who wrote the Open Source Definition, is organising the meeting, which will be held after the LinuxWorld Expo in San Francisco this August. He said IBM, Hewlett Packard and other major companies will be asked to relinquish key software patents in return for the benefits they have derived from selling open source software. According to the US Patent and Trademark Office, IBM leads the world in patents, with 2,922 granted last year -- half as many again as its nearest competitors NEC and Canon. Open software advocates say that if key software patents were released, the technology could be used in a much wider range of applications "We plan to put them on the spot," said Perens. "I don't know how much we will get out of them but we will say: 'It is time now that you are making money out of our software for you to help us with this.' I don't know if they will be nice to us or just tell us to go and get screwed." Perens, who recently joined HP as its senior strategist for Linux and open source software, said his contract with the company will not weaken his resolve to win concessions. "Under my contract I am able to protect my ethics," he said. "I am able to speak for myself and criticise HP publicly." Speaking to ZDNet News at the Content Ownership in the Digital Economy (CODE) conference in Cambridge, England, Perens said that he planned to ask the companies in particular about "patent issues in support of the open source movement". Perens said that Hewlett-Packard has already provided some money to help run the meeting, and added that he is looking for other sponsors. The meeting will be by invitation only, said Perens, who added that he had already secured the interest of several leading open source figures. Brian Behlendorf, president of the Apache Software Foundation, which oversees development of the widely used Web server software, is understood to be signed up, as is N2K chief executive Larry Rosen and Berkeley University professor Pam Samuelson. Perens added that he is also trying to get Stanford Law Schools' Professor Laurence Lessig, who played a key part in the recent antitrust trial against Microsoft. Another name on the hopefuls list is that of Richard Stallman, founder of the GNU Public Licence which is the de facto standard licence used for Open Source software. Stallman, who also attended the conference yesterday, did not indicate whether he would attend, but when Perens noted that he had received some criticism for the decision to make the meeting by invitation only, Stallman replied: "It's simple -- inviting a public audience to the negotiating table is detrimental to the negotiations." Stallman is known for his vigorous opposition to software patents of all types. Stallman said of all the software patents, the one covering the RSA cryptographic algorithm -- which has now expired -- has done most harm. "That hurt for a long time," he said. "It stopped free software being developed to do that same job." Other harmful software patents he cited include the Unisys patent that covers the compression algorithm used to generate and view GIF graphic files, and the Pantone colour matching patent: "That's why the GIMP (Graphics and image manipulation) package is no good for professional pre-press jobs." Take me to the Linux Lounge Have your say instantly, and see what others have said. Click on the TalkBack button and go to the Linux lounge Let the editors know what you think in the Mailroom. And read what others have said.