The complaint, submitted in The Hague earlier this month on behalf of the Bibas family, charges Tehran with crimes against humanity, war crimes and genocide.
Iran has denied any foreknowledge of the attacks but officialdom has cited with pride its support of what it describes as resistance groups in the region.
The two young red-headed boys Arial and Kfir became emblems of Israel's agony over the lingering hostage standoff with militants in Gaza amid an Israeli incursion that has devastated the coastal enclave and killed tens of thousands of Palestinians.
Hamas says the family was killed in an Israeli air strike while Israel counters that their captors murdered them. The father, Yarden, was also captured and released as part of an earlier prisoner swap.
The complaint alleges Iran’s leadership, including Supreme Leader Ayatollah Ali Khamenei and Islamic Revolutionary Guard Corps Quds Force commander Esmail Qaani, provided Hamas with weapons, training and coordination used in the assault.
The filing demands ICC prosecutors open a formal investigation and issue arrest warrants for both men. It argues Iran acted knowingly and intentionally in supporting Hamas, which left Bibas, her two young sons and other family members dead.
“The IRGC, at the direction of the Iranian regime and specifically Khamenei and Qaani, knowingly and intentionally provided weapons to Hamas for the purpose of killing Jews, Israelis and other affiliated members of a protected group,” the filing says.
The Bibas family tragedy resonated across Israel. For their surviving relatives, the complaint marks an attempt to hold Tehran accountable at the highest level.
The filing, submitted by former US Justice Department war-crimes prosecutor Eli Rosenbaum and human-rights lawyer Elliot Malin, argues Iran’s support for Hamas constitutes complicity in crimes against humanity, war crimes and genocide.
It cites what it calls Hamas’s own statements acknowledging Iranian backing, as well as evidence from US investigations into Tehran’s financing of regional armed groups.
Though Iran is not a party to the ICC, prosecutors have previously asserted jurisdiction over Gaza, opening the possibility of probes into outside actors. The court has not yet said whether it will act on the complaint.