A drug testing laboratory targeted by animal activists saw its shares dive by more than a third today.
Shares in Huntingdon Life Sciences fell a penny to 1.75p - valuing the company at just £5.1 million - far below its share price of more than 110p in 1997.
The share slump has mainly been brought about by animal activists who are trying to close the group down by forcing its shareholders to sell up.
The activists have also been targeting Royal Bank of Scotland, which is expected to decide by Friday whether to extend a £22.6 million loan facility to the group.
The loan repayment has been extended on a monthly basis since August, until the most recent extension date, when it was changed to a two-week timescale, Huntingdon said.
A spokesman however said: "The rationale for two weeks is nothing more than an internal meeting at RBS. They have extended it every month for five months and we are expecting them to carry on."
Huntingdon's spokesman added: "From a business point of view we have revenues of over £60 million - the business is strong."
A spokesman for RBS said he could not comment as the bank was "bound by customer confidentiality".
Greg Avery, spokesman for Stop Huntingdon Animal Cruelty, said: "We thought it would take three years to close them down but this is 12 months in and look where we are. Our only aim is to close them down. "
He said they were peaceful protesters, adding: "At the end of the day we are interested in the animals inside Huntingdon. We are against all violence."