WASHINGTON — The Supreme Court issued four decisions on Wednesday, including ones on international terrorism, whistle-blowers in securities cases and civil rights suits filed by prisoners.

International Terrorism

The court unanimously rejected an attempt by victims of three 1997 suicide bombings in Jerusalem to seize Iranian artifacts housed at the University of Chicago. The plaintiffs had won a $71.5 million judgment against Iran, which they said had been responsible for the bombings.

They sought to seize the artifacts — some 30,000 clay tablets and fragments bearing ancient writings known as the Persepolis collection — to help satisfy the judgment.

Justice Sonia Sotomayor, writing for the court, said the artifacts were shielded by the Foreign Sovereign Immunities Act, a federal law that generally bars seizing the assets of foreign states. The law has some exceptions, but Justice Sotomayor said they did not apply to the antiquities.