The pirates were asking for a $35 million ransom for the Ukrainian ship:

Somali pirates demand 35 million dollars for 'tank' ship: official

But now they're dropping it to five:

Pirates' demand now $5M for weapons vessel

Andrew Mwangura of the Kenya Seafarers Association said while pirates initially asked for $35 million for the vessel's safe return, they lowered their demand significantly due to the secondhand nature of the weapons and the fact the vessel's crew is not from the United States, CNN reported Saturday.

Meanwhile, they've released an Egyptian vessel and a Malaysian ship today. Malaysia paid the ransom, and it's likely Egypt did too, but they're not admitting it.