Five activists carried out a campaign of blackmail against firms they suspected of supplying a large animal testing laboratory, a court has heard.
The defendants are accused of using threats, including criminal damage and hoax bombs, against firms with links to Huntingdon Life Sciences in Cambridge.
The five, who are allegedly part of Stop Huntingdon Animal Cruelty (SHAC), all deny conspiracy to blackmail.
Winchester Crown Court heard SHAC had links with the Animal Liberation Front.
Michael Bowes QC, for the prosecution, said there were direct email links between the two organisations, as well as between SHAC and the Animal Rights Militia.
The court heard Trevor Holmes, 51, of Newcastle; Gerrah Selby, 20, of Chiswick, London; Daniel Wadham, 21, of Bromley, south London; Gavin Medd-Hall, 45, of Croydon, south London; and Heather Nicholson, 41, of Eversley, Hampshire, were all closely involved in the campaign from 2001 until 2007, which targeted companies in Britain and Europe.
Three others: Gregg Avery and Natasha Avery, both of Hampshire, and Daniel Amos, of no fixed address, pleaded guilty to conspiracy to blackmail, the court was told.
Jurors heard Ms Nicholson was a founder member of SHAC who managed the "menacing" campaigns against firms named on the SHAC website.
The blackmail would only stop when targeted firms put out a "capitulation statement" to SHAC to say they would no longer supply Huntingdon Life Sciences, which conducts animal testing for the pharmaceutical industry, the court was told.
During Monday's hearing, jurors were shown footage allegedly shot by the activists at Amari Plastics in 2003.
Campaigners were seen accusing the firm of making dissection boards for Huntingdon Life Sciences, and warning the firm they would be bombarded with emails.
A woman on the film said: "They are a vile company and it's quite disgusting you have anything to do with them."
The firm then says they have not had anything to do with Huntingdon Life Sciences for more than a year, and a campaigner asks for a statement to put on their website.
Other companies who had suspected dealings with the firm received hand-written notes that were shown to the jury.
One read: "Your days are numbered animal abuser. Time running out."
One manager of a company was sent a letter saying he would be stabbed with a needle infected with HIV and letters were sent to his neighbours claiming he was a paedophile, the court heard.
The trial continues.