A leading City organisation may mount civil lawsuits against animal rights extremists, it has emerged.
The NAPF is preparing a 'counter-attack' against extremists
The National Association of Pension Funds, whose members look after £650bn worth of funds, aims to stop violence and intimidation, The Times reported.
The group confirmed it is assessing the suitability of civil lawsuits.
The move follows a rash of "investor terrorism" cases, in which firms with links to animal research have had executives and shareholders threatened.
A spokesman for the NAPF said: "We are looking at civil action to see how it could be used to make sure that trustees and fund managers can invest in legitimate business."
He said that the NAPF was not opposed to legitimate protest.
Intimidation from animal rights extremists was not thought to be a problem for
pension funds at the moment, he said.
Share price drop
Animal rights extremists were blamed when a building contractor pulled out of work on a controversial animal research centre for Oxford University last week.
Shareholders received threatening letters, leading to a temporary drop in the company's share prices.
But Oxford University officials say they remain committed to building the £18m project which will see mice, amphibians and monkeys being used in the search for cures for conditions like leukaemia, Alzheimer's and asthma and others.
Research scientists reacted angrily to what they said was blatant "terrorism" and the government promised to clamp down on "internal terrorists" and give better protection to such companies.
In June, John Biles, a non-executive director of contractor the Montpellier Group, resigned after one month, citing "personal reasons".
Bosses have also had paint poured over their cars in attacks.
On Saturday, animal rights campaigners protested at the Oxford site.
About 500 people took part in a peaceful march, according to the BBC's correspondent.
Before the march, Oxford MP Dr Evan Harris said he hoped the protesters would condemn violence, intimidation and harassment.
In January, Cambridge University shelved plans for a multi-million pound primate research centre in the face of escalating costs, partly caused by the expected need to protect it from animal rights activists.
Figures published two months ago showed protesters had stepped up campaigns of violence and intimidation against scientists.
According to the Association of the British Pharmaceutical Industry statistics, there were 46 instances of damage to personal, company and public property between January and March this year - more than double the number in the first quarter of 2003.
There were also 32 visits to the homes of company directors compared with 10 in the same period last year while a total of 22 companies had severed their links with animal research providers in the first three months of the year.
The British Union for the Abolition of Vivisection says it is important that animal protesters are not classed as terrorists.
"We would never support violence either against animals or people - we are a peaceful organisation and that is fundamental to our course," said a spokeswoman.
"The government should engage in a proper debate about vivisection and listen to the many, many people who have legitimate concerns and strong
arguments and not allow all of us to be labelled as terrorists and extremists."
Liberal Democrat MP Ed Davey, who sits on the Commons science and technology committee, backed the NAPF move and called on the government to do more to protect scientists.
"It is about time that industry took some action to help protect the scientists whose work they rely on for the production of safe and effective new
medicines," he said.
There was a danger of "losing significant" investment if medical research went abroad where standards of animal welfare were "lower than in Britain", he added.