Caspar Bowden, UK privacy pioneer, mourned by tech industry
Technology industry figures and firms have been paying tribute to Caspar Bowden, a renowned digital privacy advocate, who has died of cancer.
He had campaigned against what he saw as intrusions by companies and governments on people's digital lives.
He co-founded and was director of the Foundation for Information Policy Research, an influential UK think tank.
The Electronic Frontier Foundation (EFF) said it was "shocked and saddened".
Caspar frequently had the frustrating experience of seeing his most pessimistic predictions disregarded as alarmist, only to turn out to be true all along," said the EFF's international director Danny O'Brien.
"Among a community filled with perceptive advocates for a better future, Caspar Bowden stood out as one of the most prescient and the most determined. With a far-reaching knowledge of both policy and technology, he was frequently years ahead of his contemporaries in identifying upcoming issues, and never hesitated to transform his own life and career to better meet those challenges."
Speaking to technology and security news site The Register, Privacy International's Gus Hosein said: "[Caspar Bowden] was a fervent believer in privacy, and technology's role in creating and ensuring it. He hacked legislation to see what it was that governments were trying to do and called them on it."
Mr Bowden's brother Malcolm told BBC News he hoped plans for a Caspar Bowden Foundation would come to fruition.
"Caspar loved rockets and liberty. He had an unsurpassed understanding of privacy issues, the law and the shenanigans our governments and their agencies indulge in.
"We seldom understood what he was telling us but he had most certainly convinced himself. We loved him dearly and feel his stature will surely grow."
Up until his death, Mr Bowden had been a director for the Tor Project, the non-profit group which oversees development of the Tor browser, used by many to cover their identity while on the internet.
In a statement, the Tor Project said: "Caspar was a passionate supporter of universal human rights, including the right to privacy. The world has lost a voice of tremendous moral courage."
Separately, the Tor Project's Jacob Appelbaum added: "In the hospital Caspar Bowden asked that we work to ensure equal protection regardless of nationality. Privacy is a universal human right."
During his career Mr Bowden was called upon by the European Union and others to offer detailed analysis on matters of privacy.
In the wake of the Edward Snowden revelations, Mr Bowden was asked to produce a report on the impact of US surveillance on the rights of Europeans.
Mr Bowden's Foundation of Internet Policy Research fiercely opposed the creation of the Regulation of Investigatory Powers bill, better known as Ripa, later described by the Home Affairs Select Committee as being not fit for purpose. Its powers are currently under review.
Former Liberal Democrat MP Julian Huppert - who had been on the committee - tweeted: "Shocked at the news of the death of Caspar Bowden, one of the world's leading tech privacy experts. An honour to have worked with him."
Mr Bowden also worked for Microsoft between 2002 and 2011 as a privacy strategist. He later said he had been fired for speaking out about privacy matters at the firm.
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Photograph of Caspar Bowden provided by Wikimedia Commons user Rama under a Cc-by-sa-2.0-fr licence.