Thalidomide U.K. Agency, which represents people who were affected by the drug in Britain, also rejected the apology.
Freddie Astbury, the charity's head consultant, claimed the company was only now apologizing because of court proceedings brought by victims in Australia and said it needed to "put their money where their mouth is" rather than simply express regret.
"If they are serious about admitting they are at fault and regret what happened, they need to start helping those of us who were affected financially," said Astbury, who was born in Chester in 1959 with no arms and no legs after his mother took the drug.
"Being disabled is very expensive and thalidomide people need help and care, and adaptations to their cars and homes. We just want people to live a comfortable life and that means Grünenthal have to pay for their mistake financially."
Stock was speaking in the western German city of Stolberg, where the company is based, at the inauguration of a memorial to commemorate the victims of thalidomide.
"Thalidomide is and will always be part of our company's history. We have a responsibility and we face it openly," said Stock, who added that the inauguration of the memorial had "triggered very critical reactions alongside great support".
He told the city clerk, Johannes Igel, who campaigned for the memorial: "We have chosen to support your cause, which is also the cause of many affected people. The memorial symbolizes an important milestone of a larger development. It is a development towards an ongoing dialogue, ongoing moving towards one another, incipient efforts to understand and – consequently – to act together."
"On behalf of Grünenthal with its shareholders and all employees, I would like to take the opportunity at this moment of remembrance today to express our sincere regrets about the consequences of thalidomide and our deep sympathy for all those affected, their mothers and their families."
"We see both the physical hardship and the emotional stress that the affected, their families and particularly their mothers, had to suffer because of thalidomide and still have to endure day by day."
Stock went on to say the "thalidomide tragedy" had taken place 50 years ago "in a world completely different from today".
"Grünenthal has acted in accordance with the state of scientific knowledge and all industry standards for testing new drugs that were relevant and acknowledged in the 1950s and 1960s. We regret that the teratogenic [capable of resulting in a malformation of an embryo] potential of thalidomide could not be detected by the tests that we and others carried out before it was marketed."
He added that the company wanted to address its message particularly to all the affected and their mothers, adding: "We also apologize for the fact that we have not found the way to you from person to person for almost 50 years. Instead, we have been silent and we are very sorry for that.
"We ask that you regard our long silence as a sign of the silent shock that your fate has caused us. We have learned how important it is that we engage in an open dialogue with those affected and to talk and to listen to them."
Thalidomide U.K. Agency says there are 458 people currently in the U.K. who were affected by the drug, but that for every thalidomide baby that lived there were 10 that died.
The British government expressed "sincere regret" in January 2010 for the decision to give the drug the stamp of approval and set up a funding scheme to help survivors cope.
Thalidomide was originally prescribed as a "wonder drug" for morning sickness, headaches, coughs, insomnia and colds. Babies often suffered missing or deformed limbs and extreme shortening of arms and legs, but the drug also caused malformations of the eyes and ears, genitals, heart, kidneys and digestive tract.
Intellpuke: The people who put Thalidomide on the market -- and that includes those with the Grünenthal Group AND government officials, should be serving jail terms for what they did, what it caused and for the infants' deaths. The Australian victims of Thalidomide were right to reject the company's lame apology.
You can read this article by Guardian Reporter Ben Quinn, with reporting by various news agencies; in context here: www.guardian.co.uk/society/2012/sep/01/thalidomide-campaigners-dismiss-insulting-apology