In anticipation of the US sanctions against Iranian oil exports, which were reimposed by the Trump Administration on Monday (along with additional sanctions on everything from Iranian shipping to banking and insurance), oil tankers bearing the Iranian flag have embraced a stealthy approach to keeping the oil flowing: They're 'ghosting' international trackers by turning off their transponders, rendering the ships impossible to track by anything aside from visual cues.

Iran, which is already suffering from a drop in exports to 1.8 million barrels per day, down from 2.8 million barrels at the peak, is doing everything it can to keep the crude (along with 300,000 barrels of condensate) flowing. Though Iran received a temporary reprieve from the Trump Administration's sanctions waivers granted to eight of its biggest customers, those waivers are temporary, and they were also granted with the understanding that the applicants would gradually reduce their reliance on Iranian oil.

That means the kingdom is going to need to do everything it can to help any and all customers avoid detection, and possible US sanctions (which could include barring a given country's largest banks from accessing dollars and the global dollar-based financial system). Already, the ghosting method is proving surprisingly effective: In an interview with Sputnik, the founders of one of the most popular oil-tanker tracking services, tankertracker.com, have been "utterly exhausted" trying to track Iranian ships.

"It’s the first time I’ve seen a blanket black-out. It’s very unique," said TankerTrackers co-founder Samir Madani. "Iran has around 30 vessels in the Gulf area, so the past 10 days have been very tricky, but it hasn’t slowed us down. We are keeping watch visually," said co-founder Lisa Ward.

Meanwhile, the "special purpose vehicle" - a kind of SWIFT alternative designed explicitly to help European companies avoid detection by the US - is helping to facilitate clandestine payments for Iranian crude, eliminating another methodology for tracking who, exactly, is buying Iranian crude. Iranian president Hassan Rouhani has said Iran will defy US sanctions, though both sides have insisted that they remain "open" to negotiations surrounding a new deal.

Iran has also employed another strategy from the pre-Iran deal era. The Republica is keeping six ships with a total capacity of 11 million barrels anchored offshore, allowing the "floating storage tankers" to make speedy deliveries to try and mitigate buyers' anxieties as, once they leave port, the ships will be essentially impossible to track.