Royal Dutch Shell, the big oil company, agreed to pay $15.5 million to settle a case accusing it of taking part in human rights abuses in the Niger Delta in the early 1990s, a striking sum given that the company denied any wrongdoing. The settlement, announced late Monday, came days before the start of a trial in New York that was expected to reveal details of Shell’s activities in the Niger Delta.

The announcement caps a protracted legal battle that began after the death of the Nigerian activist Ken Saro-Wiwa in 1995. Saro-Wiwa, Shell’s most prominent critic, was hanged by that country’s military regime after protesting the company’s environmental practices in the oil-rich delta, especially in his native Ogoni region. Shell continued on Monday to deny any role in the death. It called the settlement a “humanitarian gesture” meant to compensate the plaintiffs, including Saro-Wiwa’s family, for their loss.

In a statement, Malcolm Brinded, the company’s executive director for exploration and production said, “Shell has always maintained the allegations were false.”

Ten plaintiffs, including the son of Saro-Wiwa and his brother, accused Shell of using the former Nigerian regime to silence its critic and paying soldiers who had carried out human rights abuses. The suit was brought under the Alien Tort Claims Act, which has been increasingly used against human rights violations occurring overseas. So far, no corporation has been found guilty under this law.